You guys went to the root of the problem and actually worked to solve it. Hats off to the effort, hope the community review is as validating as this video.
I don't think it's a "frequency" persay, but the actual 1.8 degree step the motors are built on. You have two poles in a motor and want to both push and pull on both of them to achieve a position or "step" in between each 1.8 degrees, the finer you can adjust the voltages and the better the coil windings are relative to one an other help achieve better accurately (even coils) and smoothen the motion. My old Makerbot Replicator printed with nearly no VFA, so that was actually something new to me when i got an i3 clone about 5 years ago. Those old motors also ran very warm and with harsh stepper drivers (i think the key to it was the warm motors). I put one of the motors from my old Replicator on my newer printer's extruder and immediately heavily reduced said issue. Then i put one of the old motors on the X axis and in my tests nearly completely eliminated VFA. My assumption is first quality, then i thought about the heat.. the heat effectively acts as a voltage buffer/smoother, smoothing out the motion. Then TL-smoothers started being sold for printers with cheap stepper motors/drivers. And they defiantly do work, but will reduce the power of the motor by about 10-20% and dump it out was heat.. which is why i almost think the old motors where possibly even designed to run hot because they where in a way wasting electrical "spikes" or stepping edges as heat.
Sorry, but this sounds too good to be true. Please send out kits for community influencers like 3D Printing Nerd, Maker's Muse, Thomas Sanladerer and of course Prusa 3D for public reviews.
3:45 check out the date on this document. It‘s either from 2021 written in a date format with the year in front (which is a bit unusual) or it‘s from 2018 🤷♂️
I think this issue is also a function of motor control rather than the motor alone. I and my company design electric quad copter UAS and have discovered those same exact vibrations can be eliminated with finer/cleaner motor controls. That said, introducing fancy new motor controls into a printer may be a tough thing for most folks.
Can't imagine why Prusa didn't solve this problem and left hundreds of thousands of MK2s and MK3s with this problem if this was so easy to fix. In fact, sometimes incorrect/inappropriate driver settings can trigger current waveform distortion which does worsen vibration and usually makes abnormal noise that is easy to notice and tell. For a professional team, this problem can easily be identified with a current probe. But in most situations, on a mature product such as Original i3, the drivers are already configured properly and the current is almost a perfect sine wave, and even then, many motors still have small vibrations that are not easily observable which can still cause MRR. This is a problem due to the motor design and production. So it is often a waste of time to "optimize" an already well-configed motor control set up on a mature printer product or project. It is very misleading to say that adjusting the motor control configuration is useful.
@@Prorifi3D if it was simply physical resonance the wave artifacts wouldn't be correlated. The repeatable observed inter-layer correlation along with ability to change the wavelength strongly implicates motor control regardless of how "mature" it is supposed to be.
Only now I finally put these motors, and they work amazingly! The only problem I had was that my belts were 2mm shorter and I had to order longer ones from Aliexpress.
Wow! I just wanna say this is extreme quality technical video. It's like science article: There is a problem exist, we found it's origin, and created a product to solve it. All in 4 minutes long video
Not going to lie they made this video in a way that it makes everything they are saying sound like they are selling snake oil. I'm going to hold judgement on this until some well known in the community gets their hands on this kit.
What? On the contrary, they explained it really well, so we'll that I understood that you don't even need to use what they're selling, you should be able to use some dampers on the motor and the structure itself to see results. Their motor should help more but we can wait for reviews to see if it's that'l good.
So with 1 of my printers, I went the Klipper Input Shaper + Fluidd route. And I've seen the results myself from switching my firmware to Klipper and using Input Shaper.... but from someone with limited experience with command line utilities and someone who constantly feels out of his depth modifying firmware and gcode by hand, flashing chips on the mainboard of the printer to allow the USB connection to work, etc.... I have to tell you, I would MUCH prefer this approach. If you compare the cost of buying a pi, printing a case for it, the SD card for the pi, the power adapter with clicky switch for the pi, fans and/or heatsinks, screws to mount it to the printer, and then the time it takes to tune and manhandle your printer into behaving, purchasing a kit for $350 to not have to deal with all of that, especially when you're working with multiple printers, and downtime costs you, it just makes sense to go the upgrade route and skip klipper. Klipper has a ton of potential, and I'm not badmouthing it at all, it's great and I love to see how it's progressing, but for now, needing a production ready machine and swapping a few parts shaves hours and hours off of the tuning, troubleshooting, gcode modifying, and a lot of the manual work Klipper requires. Even if I put an octopi on every one of my printers, this upgrade seems worthwhile. I'm eager to read reviews and see how people fared with these motors.
Nice that you found a hardware solution to the problem! I do not really experience this issue on my MK3 because I run it at a reasonable speed and always have silent mode active. This also greatly reduces the vibrations and thus the severity these artifacts. Speeds I run: 2500mm/min (default printing) 3500mm/min (X/Y rapid) 1200mm/min (Z rapid) 35% (first layer override) PLA: 50% (outline) 75% (solid) 100% (support) LW-PLA 70% (outline) 80% (solid) 100% (support)
I’m trying to setup my Prusa slicer with your speed settings to see how my prints look but I’m at a lost with exactly what numbers go into the slicer. The slicer uses mm/s2 or mm/s. Could you give further direction, I would appreciate it.
@@PaDawg mm/s determines the maximum speed. mm/s2 determines how fast it gets up to maximum speed and from maximum speed back to zero. For example, if mm/s is set to 10 and mm/s2 is set to 5, it will take 2 seconds to get to a top speed of 10mm/s. If mm/s2 is set to 2, it takes 5 seconds and so on. important: the higher the acceleration is set, the chance of loosing steps (position) increases dramatically. and that will result in failed prints
@@StefsEngineering I guess what's throwing me off is your settings are mm/min. I'm not great with the tech stuff. Any chance u could email a screenshot of your slicer numbers..
@@PaDawg well that would just give the same numbers as above stated. You can devide by 60 and you will get the mm/s number. I'm using default acceleration settings, not even sure what they are set to...
Edit: wait wait wait the motor vibration cant be the only problem here. For those vibrations to manifest in features mms wide wouldn't they have to be in the 0-10 hertz range? the print head is only moving across the features peak to peak distance every 0.5 second or so. I'm confused haha Coming from FPV drones, unwanted vibrations miserable. Motors/build stability are the absolute biggest factors. However, we have a fair few "fixes" that we can employ in less than ideal situations. I'm curious how soft-mounting motors, belt tension adjustment, or increasing stiffness/ adding flex in strategic places would alter those vibrations. The name of the game in FPV is move the vibrations higher with stiffness(so it can be easily be filtered in software), and using soft mounting strategically to isolate vibrations. I'm no expert by any means, and I do want to thank you guys for putting work into application specific motor designs. My uneducated gut is telling me adding weight to the moving parts to reduce the resonance at the motors vibration frequency, and reducing/increasing the rigidity of the motor and print head coupling could help. Best option is to use the right parts in the first place though.
Soft motor mounts will absorb some of the motor torque and allow it to move which would affect the print head positioning. Think of the affect putting soft mounts on a CNC machine. All stepper motors in this application are rigidly mounted. I'm a bit skeptical of the benefit of these motors most of their claims are based on "before and after photos" and powerpoint graphs which made the video feel like a sales presentation. You would think any company involved at this level would have white papers and mounds of data which is pretty much absent from their web site. With regard to the print quality there are way too many variables involved to affect the outcome. A Prusa upgrade? Perhaps. A Voron upgrade? That remains to be seen
You can also change the mass in a vibrating system to change the resonance frequency, cutting mass for a higher frequency and adding mass for a lower frequency. I'd imagine even a rubber stepper damper might help.
I always thought, this was an issue of the motor drivers not having enough resolution. (Also since some drivers make motors be louder or more quiet.) Didn't know, that this is actually an issue of the motor itself. Great to know, that there's a fix. Might get the XY-Upgrade.
It's both. There is still the real effect that some motor drivers tend to snap to the half-step point rather than having a smooth torque curve through the microstepping positions. Cheaper drivers have less consistent microstepping, and the reason that speed affects VFA is the frequency of that snapping action near the full and half steps matching the resonance of the motor. So bad motor drivers will cause choppy and inconsistent motion, and good drivers will reduce it but only so far as the motor can handle. If the motor has inconsistent torque around the microstepping values, then it won't be able to keep up regardless of how expensive your drivers are.
Increasing microsteps helps a lot to reduce vibration on the motors, oriental motor steppers offers a plenty of technical info for their products, one interesting data is called "vibration characteristic" it displays the vibration intensity of the complete range of speed so you can decide how much vibration is acceptable...
TMC 2130 drivers on i3 MK3/S/+ are already 256 microsteps. And the vibration caused by under microstep is totally different from those which cause MRR(VFA).
This could work. On machine tools the chatter is from resonance and randomized varying feed rates makes sure time spent at the feed rate that allows resonance to build is never long enough to allow resonance to be achieved, or at least minimizes it. In 3D printing, as shown in this video, the number of artifacts, their prominence, and interval across the printed object surface all varied with speed. Perhaps by randomizing 3D printer speeds the artifacts will still be in the printed object but having been scattered around, they won't be visible as an easily identifiable pattern by casual observation.
Actually, randomized 3D printing speeds could be key to allowing faster print cycle times. Whatever non-critical artifacts that were avoided by staying under some max speed in the non-randomized speed paradigm, could be tolerated if they were scattered about using speed randomization. By randomizing, a higher average speed could be used and the print completion time could be significantly shortened.
Interesting findings, coming from the Voron community, we've had a large influx of VFA reports following a recent batch of LDO V0.1 kits, including my own. Are there any plans in the future to make these motors in kits for Voron, Ratrig, hevORT, etc? or in other standards and selling them separately NEMA14, NEMA17, Pancake, etc. Many other people and I would like to see more options for high quality stepper motors, I'm hoping you can make these innovations more open to the rest of the printing community, and I'm really glad to see a company is pushing forward to solve issues like these.
Thank you for your compliment and support! We will continue to do our best to advance the development of 3D printing technology. We are planning the optimization and production of motors adapted to other printers/of other specifications. Based on our past experience, this process may take a couple of months or even a year. And for the Voron V0.1, we happened to have done some tests on it recently. We modified some of the printed parts, adjusted the corresponding driver settings to install our NEMA17 motors with current specifications. With the limited testing we have done so far, our motors reduce the MRR(VFA) on V0.1 significantly. Our recent test results on various non-Prusa i3 printers will be organized and published soon. We will also upload all relevant modified printed parts and configurations to GitHub. If you are willing to try something new, we will also make a test motor kit with a discount available for you to test them on different machines. Follow us and stay in touch!
@@Prorifi3D Thanks a bunch for the detailed reply. Good to hear that you're making motors for other printers, and doing more research into the subject. As for the V0.1, it's nice to see that improvements are being made on the MMR issues, I'd be happy to test the modified parts for the V0.1 on my personal machine, may I get link to your GitHub so I can follow along closely? I would be interested in testing the motor kit depending on the price, I do have some questions about the NEMA17 on the V0.1. How does the NEMA17 perform compared to the stock NEMA14? Is the back panel able to be closed with the larger NEMA17 motors installed? Have you modified the frame to fit them? Is additional hardware required for the modified printed parts needed to install the NEMA17 motors onto the V0.1? Thanks for being so open with the testing process, I'm excited to see what comes when the research is released.
Would love to test a set of motors on my Printrbot simple metal! Do you only need them for the X and Y axis? Or does Z and the extruded help to be replaced with your motor model as well?
This is a really interesting idea and I think motors purpose built for 3D printing is a great idea. I saw a comment regarding Voron compatibility and was wondering if you plan on making a version with a JST connection so it can be an easier swap in replacement for people with more custom designs. Also I assume these are 1.8 degree steppers, are there any plans for a 0.9 degree version if not already existing. Also selling them individually or in 4 packs would be cool.
Thank you for your compliment and support! We have plans for other models in the future. However, there is no plan for 0.9° stepper motors since they lose much torque. We have released the Motor Development Kit, you can mod on your own: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
0.9 have less torque, but with the proper gear ratio that can be cranked up. Every big nema manufacturer has it's own 1.8 and 0.9 motor. What about multiplying the number of coils? That would make sin vawe more flat, less vibration
Cool to see a new approach to this issue, makes sense for people that want to reduce this effect but maintain the stock prusa experience. For those of you that want to eliminate this problem, the root cause is einsy Rambo board with its tmc2130s. Swap out to a different board like an Skr mini and your problems will be solved. I did every mod to eliminate these artifacts until I swapped boards about a year ago.
Thank you for your support! In theory, switching to the SKR mini board itself does not reduce MRR, but the change of slicer settings along with the board change is likely to change the printing speed which has effects on MRR. We mentioned the relation between speed and MRR in our video. You can find more on our technical details page:prorifi3d.com/pages/technical-details
At my setup (years ago), it was my extruder stepper driver! Turned out that a DRV8825 stepper driver does not turn the stepper motor smoothly enough to be unsuitable for an extruder
Same here, I wonder if I order their full kit and if I can print the parts on a friends printer, that I then have one myself. Was looking for a review but I can't find one.
pure add for noting special upgrade.... buy new steppers 5% better.... 200% overprinced.... no thans... just use better steppers in new printers... that is all
The motors do not vibrate in all directions. The location of the motors affects the VFA. When the engine is on its side, it vibrates better than when it is lying on its back and is attached to the frame from there.
It will not work. Since MRR is caused by the output of motors, add damping mounts has no use. We have a technical details page to help you understand the cause of MRR(VFA):prorifi3d.com/pages/technical-details
@@Prorifi3D Im using it for years. If the motors are in good quality, with Vibration Dampers, they give great results. You did a great improvement. But Vibration dumper with a good quality motor (If you already have the motors),, is cheaper option
Besides motors, this also confirms that the i3 series (and, to some extent, ALL prusa printers) frame is not really well engineered/built at all. Far from being stiff enough, which makes the structural upgrade (aluminum profiles) almost mandatory in the first place too. Which is crazy, considering its price tag and supposed "hi quality".
@@olafmarzocchi6194 ye but maybe the acceleration differences when printing keep the motors from resonating that much ( just like variable print speed ) ... obviously is not across the whole printing duration but input shaping might help a little ... with these motors it might solve the issue and let input shaper do its job
@@NanescuRadu1 of course these motors will improve the print results but ANY effect of the input shaper disappears after roughly a couple of millimetres from a corner.
@@olafmarzocchi6194 what i meant is … keeping the motors at the same speed will amplify the resonance … input shaper, linear advance or whatever might stop the resonance a bit not completely ofc
Thanks! You should think about making some for bambu lab printers! I was very excited about that printer and everything was good until I decided to slow it down to 120mm/s because it was to fast for my filament and every filament looked mate had zero gloss to it, when it should have, been told it was due to too fast printing. So BL told me I have two choices to slow it more down or they suggest to speed up to 200mm/s or above. And at 120 mms it is way more louder and feels like steppers about to jump out, at 200 and over it gets much smoother and quieter. Would definitely upgrade mine on BL.
I always thought it's a problem with my belts rubbing on idlers or sth else in the motion system. But neuer thought it would be just "normal" VFA. On my MK4 I printed sth that was slowed down in speed because of min layer time and had rough ripples and I thought seit something is defect or I need to replace sth. The I got the BL X1C and hat the same issue and didn't know what to say because I now had two printers with same poor quality. But just by printing very slow or always checking it prints at 200mm/s helped a lot. In some way I am happy it's an issue that is kinda normal and doesn't require a printer refund but on the other side I'm somewhat unhappy that it's an issue that can't be fixed easily and not even completely and I'm only be Abe to print at 20-40 or 170-220mm/s, everything between doesn't look good
We had similar issues on some scientific projects decades ago. Best way to get smooth motion is to avoid stepper motors, they have vibration inducing torque ripple. At some level it is inherent in their fundamental design. Properly designed servo motors (with appropriate controllers) avoid this problem. The electronics and the motor must be designed to produce constant smooth torque. Steppers are great for low cost motion but not for smooth motion. Good motor control hardware and software can go a long way toward reducing the problem. If that's not enough, and one is contemplating changing the motors, perhaps it is time to change the type of motors.
@@teeniv84 Yeah servo's are the best but really expensive to set up. not worth it tbh because everything you see in that video is just artificially made... i got 5 i3's and none of them have these issues. and just look what other people print, almost none look like it in this video.
This is mostly an issue of cogging. The magnet will try to move quicker to get to the poles producing the spike in speed and then bounce as it over shoots the step/pole due to inertia. There is a resonance aspect if you drive your next step at a certain point in the bounce (the worst probably right at the undershoot peak). To me the resonance is the secondary problem. If you completely fixed the resonance problem, you will still have patterns in the surface because the speed of the nozzle is not consistent between steps. The nozzle is in theory applying the plastic at a constant rate (but also subject to the same cogging issue, damped heavily by the friction of the plastic). If the nozzle moves at inconsistent speeds in xy while the plastic comes out at the same speed, the width of the extrusion will vary making waves. Fix the overshoot and the resonance issue goes away, but you still have smaller ripples. Fix the cogging and both go away. Making a motor with a higher number of steps, or changing to a geared down drive would make them closer together, perhaps to the point where they don't matter. Put a slight twist in the rotor and it will really soften them by getting rid of the cog, but probably compromise torque and position holding. The slicer could also do a lot to make them not noticeable by making the waves offset between layers. The surface would just have a slight roughness, but appear uniform. In theory the driver should be able to microstep them out, but theory and reality down always match. Plus the inertia of the entire system has to be tuned, not just the motor (at least for belt drive, a screw with a low enough lead to not be driven would only be affected by the screws inertia and not the print head also). Ideally the software would figure it out, but you would need position sensors to do it. It then comparing the input to the actual movement and adjusting the input until the output best matches. Another option would be to tune the extruder to push more plastic right as the faster movement between steps happens, and less as it slows on the cog/step. This may or may not be possible depending on how responsive the plastic is. I suspect the friction/viscosity will make it impractical. Microstepping would make it more complex as well.
Sadly I have never seen an independent test of these motors or from any Influencer, like CNC Kitchen oder Makers Muse. These Motors are just too expensive to give it a try, without and Tests or reviews out there, that they are actually worth the money 🤔🤷🏽♂️.
Hi, Influencers are more than welcome to test our products. If you leave a comment on their channel and they are willing to review it, we will be happy to send the products for review.
So here is the real question. My original Prusa MK2 has run for years with none of the VFA issues showing. I recently upgraded it to a MK2.5s using the Prusa upgrade kit, yes I've had the kit for a while. Now it has bad VFA's. All steppers and main board are still the original ones that came with the MK2, only change was new firmware for the MK2.5s. The only other change going to the MK2.5s was the extruder is now the dual drive with Bondtech style gears. So, considering the stepper motors were NOT changed and ran fine before the upgrade, what did change that now causes the VFA's? Slicer, print profile and material all remained the same for my tests.
During your upgrade to MK2.5S, the heatbed system was changed and the weight increased a lot: magnets under the heatbed PCB and an additional piece of spring steel. The significant increase in weight caused a significant reduction in the natural frequency of the Y-axis motion, which resonated with the output vibration of the motor, thus creating the same MRR/VFA issue on MK2.5S as on the MK3 series. The root cause of MRR is the vibration from the output of the motor, but it is important to solve MRR not only with the motor but also with the improvement of the system's natural frequency. So we have a Dual belt system and frame upgrade in addition to low vibration motors. This combination can improve the system frequency and reduce resonance. So we also recommend our frame upgrade if you don't have the Bear upgrade. With the combination of low vibration motors, a Dual belt system, and frame upgrade, MRR is almost invisible. If you wish to reduce VFA/MRR, try our products at prorifi3d.com/collections/upgrade-kit/products/kit
Very interesting findings and cool solution! maybe "stepping" away from stepper motors and switching over to linear drives would also be a solution?! In Industry applications, stepper motors are not used at all due to their lack of "knowing" where they are - ergo no encoder being present. very smooth high quality linear drives will give you no stuttering whatsoever! Also - as an intermediste solution I would love to see different stepper drivers on this issue with the same motors but maybe 256 microstepping on et cetera...
loose belt definitely increase VFA, I spend days testing prints over 300mm tall, tightening belt will decrease VFA but cause layer shift on tall and narrow parts, while loosening belt reduces layer shift but creates VFA
You still will get a ripple as this is intrinsic characteristic of steppers.Servo would be much better, but is still too expensive, to use in consumer printer.
it could be interesting to make a standalone servo that's powerful enough, precise and cheap for consumer printers... hmm maybe I could get in on doing that, a plug and play servo upgrade for printers that directly replace the nema17 with an on-board driver and encoder
Make it FOC (field oriented controal) It uses the internal windings of the bldc's to get i formations about the curent location of the Rotor. Idear is that you can skip the encoder that way. And make it mutch simpler. Its used lots in electric skatbords bilds. Both the O drive and Vesc platform supports it. if im not mistaken. Not shure how stabel it is if the rotor is requierd to stay still, and is not inducing energy in the coils to messure the position tho. But having a servo upgrade kid woud be sweet af think about the power and prindspeeds... looking at havORT servo edition.
Makes me wonder if this could be improved using dithering. And by that I mean by changing print speed chaotically within certain range selected exactly to couteract the resonance.
This sounds like something that can be easily solved in software by varying the speed of the stepper randomly to achieve an average target speed but without constant repetitions that cause resonance. I believe cnc mills and lathes already do this for the same exact reason. It would flatten the peak of the frequency response by spreading out the area to neighboring frequencies. Should work to reduce audible noise too.
Many CNC technologies can not be applied to 3D printing directly. Like the varying speed you mentioned. Because in different printing speeds the actual extrusion rate is not the same. The changing printing speed will lead to changes in extrusion width, inconsistent extrusion will show up.
Intresting research. But i think VFA is not only an effect of MRR. There are probably multiple factors playing together here. The dual BMG gears as identified by @MihaiDesigns definitely affect it as well, as printers with different extruder designs like the E3D Titan suffer less but still show this issue. My guess would be that the stepper driver and driver settings play a signifficant role as well. Specific motor-driver combinations might even improve or exxagerate the issue too. I also wonder like others already mentioned, if a belted drive reduction could lessen this issue compared to a geared reduction due to the elastic properties of the belt. I would test this theory myself if i had the resources to do so because i really think the impact of the stepper driver was overlooked in your research, at least in the way you presented your testing.
You might misrecognize MRR with some other defects. Ringing, inconsist extrusion, MRR(VFA) are different artifacts with different causes. We have a technical details page to help you understand the cause of MRR(VFA):prorifi3d.com/pages/technical-details
no because its just a LDO Nema Stepper motor nothing else... dont fall for this. if you want to save money. check your belt tensioning, bearings, idlers, stepper driver voltage and ofc print speeds. coming from someone with 15+ years experience in the 3d print industry.
0.9deg Stepper Motors for X and Y is complete garbage for printers with beds larger than 80x80. lol No torque. No Speed. Super high load on the TMC driver.
@@REDxFROG I run them on several machines and I dont have any problems with ether torque or speed. That being said, I even run them on my 300x300 voron 2.4. for high speed printing.
Then you most likely use 24V on them. I come from the older 12V age. 🤓 For some reason I don't want to try 0.9 again. 0.9° is way too high resolution for 0.4mm nozzles .
3D Printing ties into manufacturing. I would prefer MRR to stay with the definition of Metal Removal Rate. For consistency. VFA is a decent enough term.
When I have designed my own printer the last two years I have found out that many motors has vibrations. I ordered a couple of expensive Trinamic motors and they way less vibrations with any TMC driver. But then I switched to DM542 drivers and they performed even more smooth. Just waiting to see what it means to the printing since printer is not yet finished.
Have you tried to optimize the stepper driver control? I mean microstepping, motor voltage and stuff like that. Seams to me that that would already help a lot
No they just try to sell a product... their motors are from LDO and the prints they show is just bs... i print over 15+ years already and NEVER had this and i got plenty of printers myself, incl self build. and printed and still printing with plenty of brands and never seen this... and all got random brand stepper motors and drivers. they just try to sell their private labeled LDO motors.
This sounds great, but I would purchase after regular person like me gives a great review and print out proof, and then some popular influencers - but those I’m not too sure about since they can get paid for it. I need a regular reviewer … like me to give his feedback on this.
I heard that dual drive extruders make this problem worse. That's been my experience. My single drive older extruders were better than the upgraded ones when I bought the same printer years later.
@@coltenmeredith8899 The resonance from them causes vertical artefacts according to CNC kitchen and other channels. Something to do with the flaw in the way the second drive doesn't perfectly line up with the other. Or maybe it was Z banding, I can't remember for sure now. I've seen so many videos on it the last week.
@ArcanePath360 haha, so much information... Resonance causes ringing. Dual drive extruders cause a wood grain effect, it's from not having perfect concentricity. VFAs are from motors and gears, don't know why this happens. Z-wobble can be from lots of things, watch the creator of the hevort's videos
Would this help Delta printers? I definitely hit harmonics when printing with certain infill patterns and see something akin to VFA on the outside of parts. Thanks
Was the motor vibration caused by mechanical resonance in the motor, or electrical? It is common in cnc stepper motors. This causes a huge issue but seems to just cause minor vibration at the low power of 3d printers. If its electrical then have a micorstep contolernthat can actally do a high count. 1600 steps per turn can makena huge difference. Being able to select the mico steps can as well as you can try different one sto avoide the resonance.
On your website, the key advantage of these motors seems to be the variation in vibration strength between identical motors. Not the absolute vibration strength. i.e. you will still need to tune your print speed to minimise MRR, but with priorifi3D motors they should all have similar MRR elimination speeds? (instead of possibly having X and Y motors with different ideal speeds).
Ender 3 has MRR(VFA) as well. We have tested our motors on Ender 3, the result of MRR reduction is siginificant. Check here:prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
@@samroesch We did some tests and research on 0.9° steppers years ago and they do reduce MRR(VFA). However, 0.9° steppers will bring more problems than they solved: 1. The 0.9° steppers have less torque and will lose even more torque at high speed compared to 1.8° steppers. This leads to poorer performance and stability. 2. Using 0.9° steppers also gives the stepper driver a heavier burden which will generate more heat. This will further reduce the stability. 3. In addition, for Prusa i3 and many other printers, switching to 0.9° steppers means your machine is no longer compatible with the stock firmware.
Great video, thanks! I have been trying to answer the following question for a few days now and you might have a general idea: i have two motors in my hand and when i turn them, one has more "crisp" steps. The other one is more subdued. Its hard to explain better. Which one should i install? would that make a difference in general?
The experience of turning motors by hand is not suitable for all motors. The vibration intensity requires actual tests and analysis to be concluded. We recommend you install both motors on the printer, control the variables, and compare the final test results.
Interesting, but I'm curious. If some of the original pictures are from April, why did it take months to make and release this video? Also, why was that MCU/dev board blurred out?
The product development cycle is usually very long. It took us about a year to go from making low vibration motors in the lab to massive production. The blurred sensor in the video is for visual demonstration. The actual MRR vibrations measurement requires research-grade, ultra-sensitive sensing equipments.
Why don't you guys just work with Prusa to make the motors and frame from now on. Or at least offer a different kit. I can't afford to buy another frame and motors. Amazing work btw, solved the problem!
If the frequencies are known, wouldn't it be possible to noise-cancel the motor's vibrations in-slicer or even in the firmware? If the frequencies are variable, I feel some sort of calibration wouldn't be too hard.
That's what input shaping does; Klipper firmware uses an accelerometer to generate a profile to inhibits these kinds of artifacts. The firmware will vibrate the X and Y axes and use that data to cancel out the vibrations. Do a search for input shaping with Klipper installed on a single board computer or the Creality Sonic pad which simplifies the installation and optimization of your printer and has some additional features you can't get with a single board computer.
I have an Anet A8, would the metal frame and the other modifications works? I´m very interested in upgrading it. Thanks a lot fot solving this problem in 3D printing. Greetings from Spain.
The Prorifi3D Motor Development kit contains: 1*Prorifi3D A motor, 1*Prorifi3D B motor. This information is also on our web page: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit.
We do have the plans for this but the product development and production cycle is long. It is not expected to be released for at least half a year. But we are testing the adaptation of our current NEMA 17 motors on other machines. With our limited tests, most machines including Ender3 and Voron V0.1 can use our motors with modified printed parts plus some tuning on driver configurations, and the MRR(VFA) reduction is significant.
First All Aluminium V-Slot Profiles are the same so it can not be from frame... I am a engineer that has over 25 years of experince in Mechatronics.As you guys don't know what the problem is I can guarantee you the problem source is extruder gear alignment,hotend heat instability and even the same looking filament is not all same thickness every meter... 3D Printing is not a Precise manufacturing process.The nature of Additive manufacturing leaves the unwanted artifacts.Cause its nearly impossible to maintain every parameter same like filament thickness,hot end heat stability although the extruder gear shifting,pressure can be optimized but filament thickness shifting will still effect the quality...
Is it possible to find two motors with comparable res Freqs and run them on the same axis, but have them be 180* out of phase with one another to neutralize the vibrations?
If you consider a core XY printer, I don't think it can be possible, coz 1 motor drives one belt and there are atleast 3 motors for axes and 1 motor for extrusion. The point is, each motor is a t a different position and drive shaft axis angles are different
There is guy in prusa forum do this test. He swap with moon stepper. But not all moon have same quality of reduce VFA. I think from 4 maybe 1 is still got this issues.
We performed tests on Moons steppers. The differences between motors are relatively large, especially in recent batches. Some of them can even achieve our qualified standard. But in the same batch there will be some with large vibrations. For consumers, there is no gaurentee for the quality of the motors you get. Thus no gaurentee for MRR reduction.
now i realize why this sounded like TV Shop advert from the start
You guys went to the root of the problem and actually worked to solve it. Hats off to the effort, hope the community review is as validating as this video.
I don't think it's a "frequency" persay, but the actual 1.8 degree step the motors are built on. You have two poles in a motor and want to both push and pull on both of them to achieve a position or "step" in between each 1.8 degrees, the finer you can adjust the voltages and the better the coil windings are relative to one an other help achieve better accurately (even coils) and smoothen the motion.
My old Makerbot Replicator printed with nearly no VFA, so that was actually something new to me when i got an i3 clone about 5 years ago. Those old motors also ran very warm and with harsh stepper drivers (i think the key to it was the warm motors). I put one of the motors from my old Replicator on my newer printer's extruder and immediately heavily reduced said issue. Then i put one of the old motors on the X axis and in my tests nearly completely eliminated VFA. My assumption is first quality, then i thought about the heat.. the heat effectively acts as a voltage buffer/smoother, smoothing out the motion. Then TL-smoothers started being sold for printers with cheap stepper motors/drivers. And they defiantly do work, but will reduce the power of the motor by about 10-20% and dump it out was heat.. which is why i almost think the old motors where possibly even designed to run hot because they where in a way wasting electrical "spikes" or stepping edges as heat.
Nah, 0.9 degree motors cause almost the same distance in VFA patterns
Sorry, but this sounds too good to be true. Please send out kits for community influencers like 3D Printing Nerd, Maker's Muse, Thomas Sanladerer and of course Prusa 3D for public reviews.
Some of them will eventually pick it up if it gains traction. They don't do pre-alpha-testing for companies though.
3:45 check out the date on this document. It‘s either from 2021 written in a date format with the year in front (which is a bit unusual) or it‘s from 2018 🤷♂️
@@mechadense Agreed. On the other hand they often call the community's attention to fraud.
@@gorgonbert Hi :) it's usual in America
@@gorgonbert In different countries and regions, we have different date format conventions. Calling YY/MM/DD unusual is rather impolite. :D
Would love to see more reviews of this! Please reach out to more TH-camrs so we can see more reviews from community members.
I think this issue is also a function of motor control rather than the motor alone. I and my company design electric quad copter UAS and have discovered those same exact vibrations can be eliminated with finer/cleaner motor controls. That said, introducing fancy new motor controls into a printer may be a tough thing for most folks.
Can't imagine why Prusa didn't solve this problem and left hundreds of thousands of MK2s and MK3s with this problem if this was so easy to fix.
In fact, sometimes incorrect/inappropriate driver settings can trigger current waveform distortion which does worsen vibration and usually makes abnormal noise that is easy to notice and tell. For a professional team, this problem can easily be identified with a current probe. But in most situations, on a mature product such as Original i3, the drivers are already configured properly and the current is almost a perfect sine wave, and even then, many motors still have small vibrations that are not easily observable which can still cause MRR. This is a problem due to the motor design and production.
So it is often a waste of time to "optimize" an already well-configed motor control set up on a mature printer product or project. It is very misleading to say that adjusting the motor control configuration is useful.
@@Prorifi3D if it was simply physical resonance the wave artifacts wouldn't be correlated. The repeatable observed inter-layer correlation along with ability to change the wavelength strongly implicates motor control regardless of how "mature" it is supposed to be.
@@aajpeter We have a technical details page to help you understand the cause of MRR(VFA):prorifi3d.com/pages/technical-details
Only now I finally put these motors, and they work amazingly! The only problem I had was that my belts were 2mm shorter and I had to order longer ones from Aliexpress.
Wow! I just wanna say this is extreme quality technical video. It's like science article: There is a problem exist, we found it's origin, and created a product to solve it. All in 4 minutes long video
Thank you for your support!
Are you trolling? It’s an infomercial dude. They’re trying to sell you their hardware.
Excellent and informative presentation. I can never unsee MRR as ‘material removal rate’.
Its all microstepping and driver PWM frequency. But congrats on speccing out a better motor i guess.
Not going to lie they made this video in a way that it makes everything they are saying sound like they are selling snake oil. I'm going to hold judgement on this until some well known in the community gets their hands on this kit.
only having 900 subs make this even more like a snake oil
I'm almost 100% sure this is an AI video
What? On the contrary, they explained it really well, so we'll that I understood that you don't even need to use what they're selling, you should be able to use some dampers on the motor and the structure itself to see results. Their motor should help more but we can wait for reviews to see if it's that'l good.
You should show this to @MihaiDesigns, he will love it!
We really need some reviewers to try this out on a Prusa MK3s+ ...
So with 1 of my printers, I went the Klipper Input Shaper + Fluidd route.
And I've seen the results myself from switching my firmware to Klipper and using Input Shaper.... but from someone with limited experience with command line utilities and someone who constantly feels out of his depth modifying firmware and gcode by hand, flashing chips on the mainboard of the printer to allow the USB connection to work, etc.... I have to tell you, I would MUCH prefer this approach. If you compare the cost of buying a pi, printing a case for it, the SD card for the pi, the power adapter with clicky switch for the pi, fans and/or heatsinks, screws to mount it to the printer, and then the time it takes to tune and manhandle your printer into behaving, purchasing a kit for $350 to not have to deal with all of that, especially when you're working with multiple printers, and downtime costs you, it just makes sense to go the upgrade route and skip klipper.
Klipper has a ton of potential, and I'm not badmouthing it at all, it's great and I love to see how it's progressing, but for now, needing a production ready machine and swapping a few parts shaves hours and hours off of the tuning, troubleshooting, gcode modifying, and a lot of the manual work Klipper requires.
Even if I put an octopi on every one of my printers, this upgrade seems worthwhile.
I'm eager to read reviews and see how people fared with these motors.
Nice that you found a hardware solution to the problem! I do not really experience this issue on my MK3 because I run it at a reasonable speed and always have silent mode active. This also greatly reduces the vibrations and thus the severity these artifacts.
Speeds I run:
2500mm/min (default printing)
3500mm/min (X/Y rapid)
1200mm/min (Z rapid)
35% (first layer override)
PLA:
50% (outline)
75% (solid)
100% (support)
LW-PLA
70% (outline)
80% (solid)
100% (support)
I’m trying to setup my Prusa slicer with your speed settings to see how my prints look but I’m at a lost with exactly what numbers go into the slicer. The slicer uses mm/s2 or mm/s. Could you give further direction, I would appreciate it.
@@PaDawg mm/s determines the maximum speed. mm/s2 determines how fast it gets up to maximum speed and from maximum speed back to zero.
For example, if mm/s is set to 10 and mm/s2 is set to 5, it will take 2 seconds to get to a top speed of 10mm/s. If mm/s2 is set to 2, it takes 5 seconds and so on.
important: the higher the acceleration is set, the chance of loosing steps (position) increases dramatically. and that will result in failed prints
@@StefsEngineering I guess what's throwing me off is your settings are mm/min. I'm not great with the tech stuff. Any chance u could email a screenshot of your slicer numbers..
@@PaDawg well that would just give the same numbers as above stated. You can devide by 60 and you will get the mm/s number. I'm using default acceleration settings, not even sure what they are set to...
@@StefsEngineering ok, thanks much!
Edit: wait wait wait the motor vibration cant be the only problem here. For those vibrations to manifest in features mms wide wouldn't they have to be in the 0-10 hertz range? the print head is only moving across the features peak to peak distance every 0.5 second or so. I'm confused haha
Coming from FPV drones, unwanted vibrations miserable. Motors/build stability are the absolute biggest factors. However, we have a fair few "fixes" that we can employ in less than ideal situations. I'm curious how soft-mounting motors, belt tension adjustment, or increasing stiffness/ adding flex in strategic places would alter those vibrations. The name of the game in FPV is move the vibrations higher with stiffness(so it can be easily be filtered in software), and using soft mounting strategically to isolate vibrations. I'm no expert by any means, and I do want to thank you guys for putting work into application specific motor designs. My uneducated gut is telling me adding weight to the moving parts to reduce the resonance at the motors vibration frequency, and reducing/increasing the rigidity of the motor and print head coupling could help. Best option is to use the right parts in the first place though.
Soft motor mounts will absorb some of the motor torque and allow it to move which would affect the print head positioning. Think of the affect putting soft mounts on a CNC machine. All stepper motors in this application are rigidly mounted. I'm a bit skeptical of the benefit of these motors most of their claims are based on "before and after photos" and powerpoint graphs which made the video feel like a sales presentation. You would think any company involved at this level would have white papers and mounds of data which is pretty much absent from their web site. With regard to the print quality there are way too many variables involved to affect the outcome. A Prusa upgrade? Perhaps. A Voron upgrade? That remains to be seen
Your video's quality is astonishing...
You can also change the mass in a vibrating system to change the resonance frequency, cutting mass for a higher frequency and adding mass for a lower frequency. I'd imagine even a rubber stepper damper might help.
! th-cam.com/video/IjzrNoFnbcI/w-d-xo.html
I always thought, this was an issue of the motor drivers not having enough resolution.
(Also since some drivers make motors be louder or more quiet.)
Didn't know, that this is actually an issue of the motor itself.
Great to know, that there's a fix.
Might get the XY-Upgrade.
It's both. There is still the real effect that some motor drivers tend to snap to the half-step point rather than having a smooth torque curve through the microstepping positions. Cheaper drivers have less consistent microstepping, and the reason that speed affects VFA is the frequency of that snapping action near the full and half steps matching the resonance of the motor. So bad motor drivers will cause choppy and inconsistent motion, and good drivers will reduce it but only so far as the motor can handle. If the motor has inconsistent torque around the microstepping values, then it won't be able to keep up regardless of how expensive your drivers are.
@@dunkeroni Which drivers would you recommend for smoother printing?
excellent work and findings! 👏😌
Thanks!😊
Really hope you ordered some of these!
Increasing microsteps helps a lot to reduce vibration on the motors, oriental motor steppers offers a plenty of technical info for their products, one interesting data is called "vibration characteristic" it displays the vibration intensity of the complete range of speed so you can decide how much vibration is acceptable...
My findinds are the same.
TMC 2130 drivers on i3 MK3/S/+ are already 256 microsteps. And the vibration caused by under microstep is totally different from those which cause MRR(VFA).
Has anyone tested variable (random) feed speeds? This is done in CNC machining to prevent chattering.
This could work. On machine tools the chatter is from resonance and randomized varying feed rates makes sure time spent at the feed rate that allows resonance to build is never long enough to allow resonance to be achieved, or at least minimizes it. In 3D printing, as shown in this video, the number of artifacts, their prominence, and interval across the printed object surface all varied with speed. Perhaps by randomizing 3D printer speeds the artifacts will still be in the printed object but having been scattered around, they won't be visible as an easily identifiable pattern by casual observation.
Actually, randomized 3D printing speeds could be key to allowing faster print cycle times. Whatever non-critical artifacts that were avoided by staying under some max speed in the non-randomized speed paradigm, could be tolerated if they were scattered about using speed randomization. By randomizing, a higher average speed could be used and the print completion time could be significantly shortened.
@@gregfeneis609 someone just try it 🤣. Stepper resonance is weird to me so I can’t guess.
Dunno.... jury is still out on this May work.. may not. Certainly an upgraded Frame is worthwhile... but the Motors ? Arguable that.
Interesting findings, coming from the Voron community, we've had a large influx of VFA reports following a recent batch of LDO V0.1 kits, including my own.
Are there any plans in the future to make these motors in kits for Voron, Ratrig, hevORT, etc? or in other standards and selling them separately NEMA14, NEMA17, Pancake, etc.
Many other people and I would like to see more options for high quality stepper motors, I'm hoping you can make these innovations more open to the rest of the printing community, and I'm really glad to see a company is pushing forward to solve issues like these.
Thank you for your compliment and support! We will continue to do our best to advance the development of 3D printing technology.
We are planning the optimization and production of motors adapted to other printers/of other specifications. Based on our past experience, this process may take a couple of months or even a year.
And for the Voron V0.1, we happened to have done some tests on it recently. We modified some of the printed parts, adjusted the corresponding driver settings to install our NEMA17 motors with current specifications. With the limited testing we have done so far, our motors reduce the MRR(VFA) on V0.1 significantly.
Our recent test results on various non-Prusa i3 printers will be organized and published soon. We will also upload all relevant modified printed parts and configurations to GitHub. If you are willing to try something new, we will also make a test motor kit with a discount available for you to test them on different machines.
Follow us and stay in touch!
@@Prorifi3D Thanks a bunch for the detailed reply. Good to hear that you're making motors for other printers, and doing more research into the subject.
As for the V0.1, it's nice to see that improvements are being made on the MMR issues, I'd be happy to test the modified parts for the V0.1 on my personal machine, may I get link to your GitHub so I can follow along closely?
I would be interested in testing the motor kit depending on the price, I do have some questions about the NEMA17 on the V0.1.
How does the NEMA17 perform compared to the stock NEMA14?
Is the back panel able to be closed with the larger NEMA17 motors installed?
Have you modified the frame to fit them?
Is additional hardware required for the modified printed parts needed to install the NEMA17 motors onto the V0.1?
Thanks for being so open with the testing process, I'm excited to see what comes when the research is released.
@@Krush100 We will update soon!😉
@@Prorifi3D we would love one for the v-core 3! :)
Would love to test a set of motors on my Printrbot simple metal! Do you only need them for the X and Y axis? Or does Z and the extruded help to be replaced with your motor model as well?
Call! I just ordered the XY motors and will check how they work. Expect the video :)
So I got the package and it looks very nice. Time for testing :)
And the motors work. See my video: th-cam.com/video/YiA4KDcsxZ8/w-d-xo.html
This is a really interesting idea and I think motors purpose built for 3D printing is a great idea. I saw a comment regarding Voron compatibility and was wondering if you plan on making a version with a JST connection so it can be an easier swap in replacement for people with more custom designs. Also I assume these are 1.8 degree steppers, are there any plans for a 0.9 degree version if not already existing. Also selling them individually or in 4 packs would be cool.
Thank you for your compliment and support! We have plans for other models in the future. However, there is no plan for 0.9° stepper motors since they lose much torque. We have released the Motor Development Kit, you can mod on your own: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
0.9 have less torque, but with the proper gear ratio that can be cranked up. Every big nema manufacturer has it's own 1.8 and 0.9 motor.
What about multiplying the number of coils? That would make sin vawe more flat, less vibration
Great work, great video 👍
Thank you for your support!
Cool to see a new approach to this issue, makes sense for people that want to reduce this effect but maintain the stock prusa experience. For those of you that want to eliminate this problem, the root cause is einsy Rambo board with its tmc2130s. Swap out to a different board like an Skr mini and your problems will be solved. I did every mod to eliminate these artifacts until I swapped boards about a year ago.
Thank you for your support! In theory, switching to the SKR mini board itself does not reduce MRR, but the change of slicer settings along with the board change is likely to change the printing speed which has effects on MRR. We mentioned the relation between speed and MRR in our video. You can find more on our technical details page:prorifi3d.com/pages/technical-details
Will discuss this on ep1 of my show! (and it’s gonna be awesome!)
At my setup (years ago), it was my extruder stepper driver! Turned out that a DRV8825 stepper driver does not turn the stepper motor smoothly enough to be unsuitable for an extruder
Are there any outside reviews done of these motors? I'd like to see if their results can be duplicated.
Same here, I wonder if I order their full kit and if I can print the parts on a friends printer, that I then have one myself. Was looking for a review but I can't find one.
I’ll keep my kit in the cart till I see an independent review on these.
Thisi is more of an issue of cheap motors. In quality motors this is considered. And no way they created a new motor, they just rebranded it.
pure add for noting special upgrade.... buy new steppers 5% better.... 200% overprinced.... no thans... just use better steppers in new printers... that is all
The motors do not vibrate in all directions. The location of the motors affects the VFA. When the engine is on its side, it vibrates better than when it is lying on its back and is attached to the frame from there.
Nerds dont want you to know, "Stepper Motor Vibration Damper" is also used for years to reduce VFR. And it works.
It will not work. Since MRR is caused by the output of motors, add damping mounts has no use. We have a technical details page to help you understand the cause of MRR(VFA):prorifi3d.com/pages/technical-details
@@Prorifi3D Im using it for years. If the motors are in good quality, with Vibration Dampers, they give great results. You did a great improvement. But Vibration dumper with a good quality motor (If you already have the motors),, is cheaper option
@@kutay_ozkeskin In what application?
Besides motors, this also confirms that the i3 series (and, to some extent, ALL prusa printers) frame is not really well engineered/built at all. Far from being stiff enough, which makes the structural upgrade (aluminum profiles) almost mandatory in the first place too. Which is crazy, considering its price tag and supposed "hi quality".
Klippers input shaper does a great job of compensating for this. I would wonder how these motors with input shaper would do.
probably ridiculously smooth!
No this is not really what input shaping corrects. This is intrinsic to the motors, not related to acceleration.
@@olafmarzocchi6194 ye but maybe the acceleration differences when printing keep the motors from resonating that much ( just like variable print speed ) ... obviously is not across the whole printing duration but input shaping might help a little ... with these motors it might solve the issue and let input shaper do its job
@@NanescuRadu1 of course these motors will improve the print results but ANY effect of the input shaper disappears after roughly a couple of millimetres from a corner.
@@olafmarzocchi6194 what i meant is … keeping the motors at the same speed will amplify the resonance … input shaper, linear advance or whatever might stop the resonance a bit not completely ofc
Thanks! You should think about making some for bambu lab printers! I was very excited about that printer and everything was good until I decided to slow it down to 120mm/s because it was to fast for my filament and every filament looked mate had zero gloss to it, when it should have, been told it was due to too fast printing. So BL told me I have two choices to slow it more down or they suggest to speed up to 200mm/s or above. And at 120 mms it is way more louder and feels like steppers about to jump out, at 200 and over it gets much smoother and quieter. Would definitely upgrade mine on BL.
I always thought it's a problem with my belts rubbing on idlers or sth else in the motion system. But neuer thought it would be just "normal" VFA.
On my MK4 I printed sth that was slowed down in speed because of min layer time and had rough ripples and I thought seit something is defect or I need to replace sth. The I got the BL X1C and hat the same issue and didn't know what to say because I now had two printers with same poor quality. But just by printing very slow or always checking it prints at 200mm/s helped a lot.
In some way I am happy it's an issue that is kinda normal and doesn't require a printer refund but on the other side I'm somewhat unhappy that it's an issue that can't be fixed easily and not even completely and I'm only be Abe to print at 20-40 or 170-220mm/s, everything between doesn't look good
At this point you should sell a printer, not an upgrade kit
Ogrinals look play a trick on your mind making it look nicer. Yall did awesome.
These are cool and all but $100 for **two** steppers? I feel like there are better ways to combat this
Wow, I was way off with my already insane 80 bucks estimate lmao
I would totally get in on this for a try
We had similar issues on some scientific projects decades ago. Best way to get smooth motion is to avoid stepper motors, they have vibration inducing torque ripple. At some level it is inherent in their fundamental design. Properly designed servo motors (with appropriate controllers) avoid this problem. The electronics and the motor must be designed to produce constant smooth torque. Steppers are great for low cost motion but not for smooth motion. Good motor control hardware and software can go a long way toward reducing the problem. If that's not enough, and one is contemplating changing the motors, perhaps it is time to change the type of motors.
Then SERVO motors?
easy to fix, lower belt tensions and lower stepper voltages and don't go over the mechanical speeds of a printer. some can print faster than orthers.
@@teeniv84 Yeah servo's are the best but really expensive to set up. not worth it tbh because everything you see in that video is just artificially made... i got 5 i3's and none of them have these issues. and just look what other people print, almost none look like it in this video.
This is mostly an issue of cogging. The magnet will try to move quicker to get to the poles producing the spike in speed and then bounce as it over shoots the step/pole due to inertia. There is a resonance aspect if you drive your next step at a certain point in the bounce (the worst probably right at the undershoot peak).
To me the resonance is the secondary problem. If you completely fixed the resonance problem, you will still have patterns in the surface because the speed of the nozzle is not consistent between steps. The nozzle is in theory applying the plastic at a constant rate (but also subject to the same cogging issue, damped heavily by the friction of the plastic). If the nozzle moves at inconsistent speeds in xy while the plastic comes out at the same speed, the width of the extrusion will vary making waves.
Fix the overshoot and the resonance issue goes away, but you still have smaller ripples. Fix the cogging and both go away.
Making a motor with a higher number of steps, or changing to a geared down drive would make them closer together, perhaps to the point where they don't matter. Put a slight twist in the rotor and it will really soften them by getting rid of the cog, but probably compromise torque and position holding.
The slicer could also do a lot to make them not noticeable by making the waves offset between layers. The surface would just have a slight roughness, but appear uniform.
In theory the driver should be able to microstep them out, but theory and reality down always match. Plus the inertia of the entire system has to be tuned, not just the motor (at least for belt drive, a screw with a low enough lead to not be driven would only be affected by the screws inertia and not the print head also).
Ideally the software would figure it out, but you would need position sensors to do it. It then comparing the input to the actual movement and adjusting the input until the output best matches.
Another option would be to tune the extruder to push more plastic right as the faster movement between steps happens, and less as it slows on the cog/step. This may or may not be possible depending on how responsive the plastic is. I suspect the friction/viscosity will make it impractical. Microstepping would make it more complex as well.
Great explanation. I need to find quality 0.9deg steppers.
Great job! Did think of solving the wood grain pattern problem? That is another headache in the industry, at both hobby and professional level.
Thank you for your support!
th-cam.com/video/32dTLRNIYmw/w-d-xo.html
Maybe this helps you with you problem 👍
Sadly I have never seen an independent test of these motors or from any Influencer, like CNC Kitchen oder Makers Muse. These Motors are just too expensive to give it a try, without and Tests or reviews out there, that they are actually worth the money 🤔🤷🏽♂️.
Hi, Influencers are more than welcome to test our products. If you leave a comment on their channel and they are willing to review it, we will be happy to send the products for review.
So here is the real question. My original Prusa MK2 has run for years with none of the VFA issues showing.
I recently upgraded it to a MK2.5s using the Prusa upgrade kit, yes I've had the kit for a while. Now it has bad VFA's. All steppers and main board are still the original ones that came with the MK2, only change was new firmware for the MK2.5s.
The only other change going to the MK2.5s was the extruder is now the dual drive with Bondtech style gears.
So, considering the stepper motors were NOT changed and ran fine before the upgrade, what did change that now causes the VFA's? Slicer, print profile and material all remained the same for my tests.
During your upgrade to MK2.5S, the heatbed system was changed and the weight increased a lot: magnets under the heatbed PCB and an additional piece of spring steel. The significant increase in weight caused a significant reduction in the natural frequency of the Y-axis motion, which resonated with the output vibration of the motor, thus creating the same MRR/VFA issue on MK2.5S as on the MK3 series.
The root cause of MRR is the vibration from the output of the motor, but it is important to solve MRR not only with the motor but also with the improvement of the system's natural frequency. So we have a Dual belt system and frame upgrade in addition to low vibration motors. This combination can improve the system frequency and reduce resonance. So we also recommend our frame upgrade if you don't have the Bear upgrade. With the combination of low vibration motors, a Dual belt system, and frame upgrade, MRR is almost invisible.
If you wish to reduce VFA/MRR, try our products at prorifi3d.com/collections/upgrade-kit/products/kit
I need these motors.
Right? Although, I believe you can also suppress mrr using diode feedback arrays which can be installed in the wire loom going to the motor.
Very interesting findings and cool solution!
maybe "stepping" away from stepper motors and switching over to linear drives would also be a solution?!
In Industry applications, stepper motors are not used at all due to their lack of "knowing" where they are - ergo no encoder being present.
very smooth high quality linear drives will give you no stuttering whatsoever!
Also - as an intermediste solution I would love to see different stepper drivers on this issue with the same motors but maybe 256 microstepping on et cetera...
Thank you for your compliment and support!
loose belt definitely increase VFA, I spend days testing prints over 300mm tall, tightening belt will decrease VFA but cause layer shift on tall and narrow parts, while loosening belt reduces layer shift but creates VFA
holy shit man this ad video was generated by AI three years ago , fascinating
it's just a voice synthesizer though?? this is like 20 years old technologu
or you could put Klipper on it and tune it for resonance.
Does the prusa mini use this motor? It’s completely absent of MRR
You still will get a ripple as this is intrinsic characteristic of steppers.Servo would be much better, but is still too expensive, to use in consumer printer.
it could be interesting to make a standalone servo that's powerful enough, precise and cheap for consumer printers... hmm maybe I could get in on doing that, a plug and play servo upgrade for printers that directly replace the nema17 with an on-board driver and encoder
Make it FOC (field oriented controal) It uses the internal windings of the bldc's to get i formations about the curent location of the Rotor.
Idear is that you can skip the encoder that way. And make it mutch simpler.
Its used lots in electric skatbords bilds. Both the O drive and Vesc platform supports it. if im not mistaken.
Not shure how stabel it is if the rotor is requierd to stay still, and is not inducing energy in the coils to messure the position tho.
But having a servo upgrade kid woud be sweet af think about the power and prindspeeds... looking at havORT servo edition.
Makes me wonder if this could be improved using dithering. And by that I mean by changing print speed chaotically within certain range selected exactly to couteract the resonance.
like input shaping but for the motors as well as the frame! I wonder if you could hack that together with input shaping tools that already exist.
Klipper input shaper is good enough, especially auto tuning with accelerator adxl345.
So MK4 solved the problem by using your motors?
Nice... 🤔
no, they use 0.9 degree motors
@@MrBlackmidi1234567890987654321 So they solved nothing...
nost NEMA 17 motors have a 1.8 degree motors which most 3d printers use@@Zemistr3D
This sounds like something that can be easily solved in software by varying the speed of the stepper randomly to achieve an average target speed but without constant repetitions that cause resonance. I believe cnc mills and lathes already do this for the same exact reason. It would flatten the peak of the frequency response by spreading out the area to neighboring frequencies. Should work to reduce audible noise too.
Many CNC technologies can not be applied to 3D printing directly. Like the varying speed you mentioned. Because in different printing speeds the actual extrusion rate is not the same. The changing printing speed will lead to changes in extrusion width, inconsistent extrusion will show up.
@@Prorifi3D I'd love to see someone try, I doubt it's that bad
Intresting research. But i think VFA is not only an effect of MRR. There are probably multiple factors playing together here. The dual BMG gears as identified by @MihaiDesigns definitely affect it as well, as printers with different extruder designs like the E3D Titan suffer less but still show this issue. My guess would be that the stepper driver and driver settings play a signifficant role as well. Specific motor-driver combinations might even improve or exxagerate the issue too. I also wonder like others already mentioned, if a belted drive reduction could lessen this issue compared to a geared reduction due to the elastic properties of the belt. I would test this theory myself if i had the resources to do so because i really think the impact of the stepper driver was overlooked in your research, at least in the way you presented your testing.
You might misrecognize MRR with some other defects. Ringing, inconsist extrusion, MRR(VFA) are different artifacts with different causes. We have a technical details page to help you understand the cause of MRR(VFA):prorifi3d.com/pages/technical-details
Are you planning to release motors specifically for Bambu printers? Their printers suffer big time from VFA and I
would be glad to upgrade the motors
So, you basically found the holy grail of stepper motor design?
no because its just a LDO Nema Stepper motor nothing else... dont fall for this. if you want to save money. check your belt tensioning, bearings, idlers, stepper driver voltage and ofc print speeds. coming from someone with 15+ years experience in the 3d print industry.
I solved it by using 0.9° steppers.
Saves you a lot of money too
0.9deg Stepper Motors for X and Y is complete garbage for printers with beds larger than 80x80. lol
No torque. No Speed. Super high load on the TMC driver.
@@REDxFROG I run them on several machines and I dont have any problems with ether torque or speed. That being said, I even run them on my 300x300 voron 2.4. for high speed printing.
Then you most likely use 24V on them.
I come from the older 12V age. 🤓
For some reason I don't want to try 0.9 again. 0.9° is way too high resolution for 0.4mm nozzles .
@@REDxFROG Correct, 24V on all printers. Imho the difference between 1.8 and 0.9 is real when it comes to VFAs.
3D Printing ties into manufacturing. I would prefer MRR to stay with the definition of Metal Removal Rate. For consistency. VFA is a decent enough term.
would those stepper motor dampening mounts also help with this problem?
It will not work. Since MRR is caused by the output of motors, add damping mounts has no use.
When I have designed my own printer the last two years I have found out that many motors has vibrations. I ordered a couple of expensive Trinamic motors and they way less vibrations with any TMC driver. But then I switched to DM542 drivers and they performed even more smooth. Just waiting to see what it means to the printing since printer is not yet finished.
nah... that's not the solution.
@@REDxFROG maybe not for this. We will see. At least it makes ringing of the whole head a lot less.
@@REDxFROG could be same as they are talking about since motor may have less resonance and even resonance moved to some other rpm.
Have you tried to optimize the stepper driver control? I mean microstepping, motor voltage and stuff like that. Seams to me that that would already help a lot
No they just try to sell a product... their motors are from LDO and the prints they show is just bs... i print over 15+ years already and NEVER had this and i got plenty of printers myself, incl self build. and printed and still printing with plenty of brands and never seen this... and all got random brand stepper motors and drivers. they just try to sell their private labeled LDO motors.
@@Underp4ntz_Gaming_Channel If you never have had a problem with your surface prints from a prusa then you just dont see it.
Yeah, seems like changing from giant discrete steps to small discrete micro steps would make it all go away, or at least divide it by 16 or so. ;)
This sounds great, but I would purchase after regular person like me gives a great review and print out proof, and then some popular influencers - but those I’m not too sure about since they can get paid for it. I need a regular reviewer … like me to give his feedback on this.
Prusa be like🥱and then solving it him self while making bigger print resolution
I heard that dual drive extruders make this problem worse. That's been my experience. My single drive older extruders were better than the upgraded ones when I bought the same printer years later.
That's not VFAs, but dual drive extruders do cause an interesting problem.
@@coltenmeredith8899 The resonance from them causes vertical artefacts according to CNC kitchen and other channels. Something to do with the flaw in the way the second drive doesn't perfectly line up with the other. Or maybe it was Z banding, I can't remember for sure now. I've seen so many videos on it the last week.
@ArcanePath360 haha, so much information... Resonance causes ringing. Dual drive extruders cause a wood grain effect, it's from not having perfect concentricity. VFAs are from motors and gears, don't know why this happens. Z-wobble can be from lots of things, watch the creator of the hevort's videos
I'd love to see how a belted gear reduction would play into the defect using standard motors vs yours.
Not a bad idea!
Is it possible to damp the ripple by adding ferrofluid into normal stppermotor ?
Doesn't this problem go away with stepper motor driver upgrade?
These are stepper motors. It's not resonance, it's the process of moving in steps that causes the ripples.
Would this help Delta printers? I definitely hit harmonics when printing with certain infill patterns and see something akin to VFA on the outside of parts. Thanks
For non-i3 we have a Development Kit: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
hiya, are you guys considering making this type of motor for the E3D Hemera and its pancake version that is coming soon?
Was the motor vibration caused by mechanical resonance in the motor, or electrical?
It is common in cnc stepper motors. This causes a huge issue but seems to just cause minor vibration at the low power of 3d printers.
If its electrical then have a micorstep contolernthat can actally do a high count. 1600 steps per turn can makena huge difference.
Being able to select the mico steps can as well as you can try different one sto avoide the resonance.
Mechanical resonance. Thus this is harder to solve than electronic problems and the cost is much higher. Fortunately, we solved this issue.
I would love to test those new stepper motors and frame!
Be great to upgrade my Artillery Sidewinder.
On your website, the key advantage of these motors seems to be the variation in vibration strength between identical motors. Not the absolute vibration strength. i.e. you will still need to tune your print speed to minimise MRR, but with priorifi3D motors they should all have similar MRR elimination speeds? (instead of possibly having X and Y motors with different ideal speeds).
I believe the ender 3 achieves better results because of their inferior bearings. The rubber rollers help to dampen the motor.
Ender 3 has MRR(VFA) as well. We have tested our motors on Ender 3, the result of MRR reduction is siginificant. Check here:prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
@@Prorifi3D Thanks for the response. Have you done any comparisons against 0.9 deg steppers?
@@samroesch We did some tests and research on 0.9° steppers years ago and they do reduce MRR(VFA). However, 0.9° steppers will bring more problems than they solved:
1. The 0.9° steppers have less torque and will lose even more torque at high speed compared to 1.8° steppers. This leads to poorer performance and stability.
2. Using 0.9° steppers also gives the stepper driver a heavier burden which will generate more heat. This will further reduce the stability.
3. In addition, for Prusa i3 and many other printers, switching to 0.9° steppers means your machine is no longer compatible with the stock firmware.
Great video, thanks! I have been trying to answer the following question for a few days now and you might have a general idea: i have two motors in my hand and when i turn them, one has more "crisp" steps. The other one is more subdued. Its hard to explain better. Which one should i install? would that make a difference in general?
The experience of turning motors by hand is not suitable for all motors. The vibration intensity requires actual tests and analysis to be concluded. We recommend you install both motors on the printer, control the variables, and compare the final test results.
Considering that you're building on open source, you should be going in to more detail as to how you solved these problems.
this motor and klippers input shaper would be sick
Interesting, but I'm curious.
If some of the original pictures are from April, why did it take months to make and release this video?
Also, why was that MCU/dev board blurred out?
The product development cycle is usually very long. It took us about a year to go from making low vibration motors in the lab to massive production. The blurred sensor in the video is for visual demonstration. The actual MRR vibrations measurement requires research-grade, ultra-sensitive sensing equipments.
Why don't you guys just work with Prusa to make the motors and frame from now on. Or at least offer a different kit. I can't afford to buy another frame and motors. Amazing work btw, solved the problem!
Thank you for your support!
my Voron V2.4 would love some new quieter steppers x)
Nice work!
This seems really legit
Thank you for your support!
If the frequencies are known, wouldn't it be possible to noise-cancel the motor's vibrations in-slicer or even in the firmware? If the frequencies are variable, I feel some sort of calibration wouldn't be too hard.
That's what input shaping does; Klipper firmware uses an accelerometer to generate a profile to inhibits these kinds of artifacts. The firmware will vibrate the X and Y axes and use that data to cancel out the vibrations. Do a search for input shaping with Klipper installed on a single board computer or the Creality Sonic pad which simplifies the installation and optimization of your printer and has some additional features you can't get with a single board computer.
Far cheaper than buying new motors and over-engineered pulleys! Ordered a triangle labs board kit.. thanks for the tip @ElectronicsPeddler! 👌
Where can you download the free settings that were mentioned? I don't see them on the site.
do these motors still have a bad resonance with StealthChop at high speeds?
I have an Anet A8, would the metal frame and the other modifications works? I´m very interested in upgrading it.
Thanks a lot fot solving this problem in 3D printing.
Greetings from Spain.
For non-i3 we have a Development Kit: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit
This motors with steper drivers like MKS SERVO42C could be the solution to many quality problems when printing at higher speeds.
What does the "Prorifi3D Motor Development Kit" include? There's no information on what you get with it
The Prorifi3D Motor Development kit contains: 1*Prorifi3D A motor, 1*Prorifi3D B motor. This information is also on our web page: prorifi3d.com/collections/upgrade-kit/products/prorifi3d-motor-development-kit.
Great video, subbed. when are you going to make steppers for other printers?
We do have the plans for this but the product development and production cycle is long. It is not expected to be released for at least half a year.
But we are testing the adaptation of our current NEMA 17 motors on other machines. With our limited tests, most machines including Ender3 and Voron V0.1 can use our motors with modified printed parts plus some tuning on driver configurations, and the MRR(VFA) reduction is significant.
First All Aluminium V-Slot Profiles are the same so it can not be from frame... I am a engineer that has over 25 years of experince in Mechatronics.As you guys don't know what the problem is I can guarantee you the problem source is extruder gear alignment,hotend heat instability and even the same looking filament is not all same thickness every meter... 3D Printing is not a Precise manufacturing process.The nature of Additive manufacturing leaves the unwanted artifacts.Cause its nearly impossible to maintain every parameter same like filament thickness,hot end heat stability although the extruder gear shifting,pressure can be optimized but filament thickness shifting will still effect the quality...
Nice add!
Possible to also attach these motors to say a Anycubic Vyper?
Cant this just be solved with input shaper? Also 99$ for two steppers is outrageous
Is it possible to find two motors with comparable res Freqs and run them on the same axis, but have them be 180* out of phase with one another to neutralize the vibrations?
If you consider a core XY printer, I don't think it can be possible, coz 1 motor drives one belt and there are atleast 3 motors for axes and 1 motor for extrusion. The point is, each motor is a t a different position and drive shaft axis angles are different
Can you make available just the motors? I don’t have a Prusa, but I want to retrofit the motors
There is guy in prusa forum do this test. He swap with moon stepper.
But not all moon have same quality of reduce VFA. I think from 4 maybe 1 is still got this issues.
We performed tests on Moons steppers. The differences between motors are relatively large, especially in recent batches. Some of them can even achieve our qualified standard. But in the same batch there will be some with large vibrations. For consumers, there is no gaurentee for the quality of the motors you get. Thus no gaurentee for MRR reduction.
Very cool.