Two Z banding fixes for your 3D printer from the community
ฝัง
- เผยแพร่เมื่อ 7 พ.ค. 2024
- Z banding is a frustrating artefact that can ruin 3D printer quality. Even worse, it can be very hard to pin down the root cause and apply a fix. Two of my patrons, Derek and Patrick, have designed well considered potential solutions for Z banding. In this video, I try them out on two of my machines.
Although these specific fixes didn’t improve the print quality of my printers, that doesn’t mean they won’t be suitable for yours. I like the design for each and how they aim to address Z axis problems.
0:00 Introduction
0:41 What is Z banding/wobble?
RepRap forum thread by appjaws1: reprap.org/forum/read.php?340...
CNCKitchen video on Z banding effect of bed heating method: • PID vs Bang-Bang Tempe...
1:34 My target printers
Dual Z steppers on Ender 3: • 3 ways to add a dual Z...
Input Shaping for Marlin: • Marlin Input Shaping -...
Z banding test tower: www.printables.com/model/3936...
3:16 Community fix 1 printing and assembly
Z-Axis Stepper Motor Mount with integrated Axial Thrust bearing by djos_1475:
www.printables.com/model/8858...
Thrust bearing on Amazon: amzn.to/3jLgNKa
6:02 Community fix 2 printing and assembly
Z Stepper X-Y Axis Float Cage by Portzal3D
Download on Printables: www.printables.com/model/3921...
3mm ball bearing on Amazon: amzn.to/3RO4lpK
10:18 Fitment to printers
10:53 Test prints and results
12:02 Conclusion
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The reason for play in the steppers is because the lamination stack is slightly variable in length, so there has to be some gap to the bearing. The bottom bearing is sprung to take up the end play. If you axis is heavier than the spring tension it will exhibit end play. One way around it is to hang the axis from the motor at the top.
Two things really helped my z axis issues. I noticed in Octoprint that my bed temps were fluctuating in a +/- 1.0 degree range. Doing a bed PID tune has it down to a 0.1-0.2 degree range. Second was flow rate. Printing the flow cube test gave me a new flow rate of 85.11.
Really fantastic mods! Thanks, Michael! 😃
Stay safe there with your family! 🖖😊
love the big smile at the end of the videos :) thanks so much for your great content michael
Great job of explaining each option. Both options are inexpensive to try and easily reversible.
...And neither fixes the issue 🧐
@@kloakovalimonada his issue. Obviously they worked wonders for the Creators of those files.
I thought I had z-axis wobble, but it seemed to come and go depending on the filament. After experimenting, I discovered a humidity gradient in my storage area which was causing my filament reels to be more slightly more hydrated on one side than the other, this meant a slight expansion of the extruded filament for one side compared to the other, which meant alternating bands of 'smoother' and 'rougher' outside walls to my prints. A slight redesign of my storage area and a stricter regime of pre-printing drying fixed this.
There is a video from MirageC talking exactly about it
@@alainthire I've fixed my issue, but thanks anyway.
I've never had this problem with any of my printers but I also make sure my leadscrews are straight and accurately aligned. I use bearing blocks to support the leadscrew at the top and allow the leadscrew nut to float on ptfe grease. Thing is, unlike most all of the assembly videos on the Internet, I take the time to properly align both z uprights for square and parallel alignment as well as ensuring the connecting brackets on the x are in absolute alignment from one side to the next. I use shims where necessary so it's time consuming but I know that everything runs along its respective axis without off-axis interference. The critical part afterall is the mating shoulder of the screw nut being able to sit squarely on the carriage bracket and correspondingly, as important - the screw having even contact with the flanks of the internal screw thread. Can't really do that on one lead screw unless you set it up under a preload condition - but proper, accurate assembly and alignment should be everyone starting point imo.
#2 is like a DIY oldham coupler :D Nice work! thanks for sharing!
Integrated lead screw stepper motors work wonders, especially paired with rails/rods. I got a TR8x2 single start lead screw and had exceptional results (after adjusting rotation distance).
First: Thank you for your tests and the time and material it took. Second: I prefer a belt between the two z-axes. Adjust once, good forever. Independent z-axes however, driven by two steppers can easily go out of alignment as soon as the steppers are powered off. To overcome that problem you need to bring both z-axes in sync every time you start a print. After using both alternatives I prefer a belt sync.
Nonsense ! Simply fit SINGLE start Z scews and Virtually ALL Z synch issues as well as dropping from gravity problems..disapear.
@@barenekid9695 "Simply fit SINGLE start Z scews" what does that even mean?🤔
@@citronski Typical lead screws used are four-start. That means they move the z-axis up/down four times as much as a single-start lead screw. It also means that they are more prone to move when the stepper motor is not powered.
#2 is pretty cool, I have been using a very similar mod that makes the nut on the gantry float over XY for a slightly bent z rod. I wonder which one works better. I am planning to swap to a belted Z soon though.
I just installed belted z on my cr-10s after I dealt with a lot of wobble from bent rods. It's a really fun interesting little mod.
did it solve your problem?
@@gil80 it did! Made me realize other problems too lol
I am aware this post was 4 months ago :-) What setup/kit did you go for with the belted z? Regards /Robert
It is really important that the motor-to-screw coupler fits snugly to both. Many printers come with couplers that allow a ridiculous amount of play. You'll see this as Z wobble at the bottom of your print that slowly decreases as the print gets higher. The printable self-centering couplers do a good job. If one of those springy couplers fits best, you can print a vase-mode slip-on sleeve to stiffen them up.
love your work man 😍🥰
The best "fix" for lead screw problems (I've found), especially on i3 style machines (ie. Enders), is the "belted Z mod". One unexpected perk of this mod is being able to use fast "Z hop" movements consistently on an i3, which normally isn't possible. If you have extra spare parts and hardware laying around, it's a very "low cost" solution. Oh, and there's no reason a similar solution couldn't be adapted/designed for the E5 style machines that the bed moves in the Z.
I'm currently just waiting on the hardware for this kit, I have all the printed parts printed. I'm excited to see if this fixes my issues that I've had sense doing the dual z rod mod on my ender3
Thanks to the community for the mods, but, to be honest, they seem a bit redundant to other components: the floating Z one is an interesting way of basically building a flexible coupling. Mount such a piece so it rests on the stepper axle and it's the same. Given you'll have to buy the ball bearings anyway, might as well go for the coupling.
The axial bearing mount one is pretty nice, I like this kind of approach as it does what mechanically should have been done to begin with, but because of the low loads no manufacturer does. Still, you could just place the bearing between motor and coupler without the mod anyway, couldn't you? I guess it does hold it better for the 5mm shaft with 8mm hole on the bearing tho.
For my Geeetech I3 clone I used an Anti-Z wobble-piece that isolates movements from the leadscrews so it can move in X and Y directions. This worked great on that printer.
For the first fix, you can still use a flexible coupling with a ball bearing between the stepper shaft and the lead screw. This allows the coupling to absorb any deflection from a bent lead screw. Alex Kenis has a video on how it works on his channel under something like "ball bearing trick"
This does still put axial load on the stepper, though. The best solution is to decouple the motor from the screw with a belt, then put an 8mm OD miniature thrust bearing UNDER the lead screw (to support the weight) and a KFL08 pillow block bearing around the base of the screw (to allow angular misalignment/bent screws etc), and leave the top of the screw unconstrained. This gives you the best of all worlds. Sadly, most people will consider it too much work. Deckingman has this on his monstrously large machine.
" and leave the top of the screw unconstrained"
Last summer I added a Microswiss NG Direct drive to my Ender 3 Pro. At the same time I added a TH3D dual Z kit that uses a timing belt to compensate for the added weight on the X gantry.
For the next 5 months I fought a z-banding issue. Rebuilt the x gantry, double checked the Z rods for being straight, shimmed the z stepper, tried different lubricant on the Z rod threads. I just about gave up a resigned myself to having banding. Not bad, but noticeable.
Then about a month ago I gave it one last run. I replaced the Creality supplied Z stepper motor mount with an aluminum machined bracket and changed the T nut the stepper side with an Oldham coupler. My banding is now a thing of the past am am very pleased at what is being printed.
Interesting fix! Where did you find the machined mount?
@@Twin_Flyer Amazon... Upgrade Metal Ender 3 Z Axis Stepper Motor Fixed Mount Installation Bracket for Ender3 V2 Ender3 Pro CR10 CR-10 V2 V3 CR10S PRO Z-Axis with 2040 Aluminum Profiles 3D
@@larrybowers Thanks!
Now that I reread my post and see the misspellings, one of the changes I made a few months ago when chasing the problem was replacing the brass 'T' nuts with Delrin (POM) ' T' nuts. I think that did improve the quality slightly.
Disabling z hop fixed the issue for me and I think it will for you too, I was getting perfect input shaper test but terrible regular prints.
My conclusion is it’s due to the loose bolts holding the leadscrew nuts, they are designed to be loose to allow for leadscrew play but it introduces its own backlash (between the plate and the nut).
Disabling z hop is a temporary fix and I plan to install wobblex ws8 couplings in the near future.
Edit: just noticed your latest video 😂 good to see we are on the same path
Great video, I have a JG Maker that does this and it's been frustrating to resolve
Remove the entire coupling since both cylinder are not coaxial because in part of the set screws + components tolerances. You can buy motor with lead screw included (and coaxial). It greatly improve. But it is not the only issue causing z wobbles. You need to compensate for X and Y movement, block Z movement and motor rotation otherwise you loose on z precision. Other issues can be related to extruder precision, once again with set screw causing coaxial offset, gear coax offset again... Check the issue frequency and check the potential cause frequency to find a match.
If you happen to be using the Sovol SV04, note that the part for solution 1 will lower the motor too much and the horizontal rails at the bottom will be in the way. I'm sure you could just cut out the part that is interfering with the rail, but I'm still pretty new to this and not sure how to do that. Just a note for any other beginners with this printer that may have been looking for a "print and play" solution.
I put the thrust races on my Ender 5 Plus that made a difference but since then have added linear rails to the Z axis and removed the guide rods. Have Z axis auto-align and it appears that it is going quite well.
Like you, the printers that need it the most for me is my ender 5 plus'. Hopefully someone can take this mod on!
The vertical rails that the carriage rides on should largely eliminate any wobble due to the lead screw. Sure if there are large amounts of lead screw wobble they will put force on the carriage which can then flex, but it would probably have to be extreme. I don't know why over constrained lead screws as so common though. The one end should be free to move for a reason, which is what these designs are fixing.
In the samples you showed (not the towers) that looked like extrusion problems to me. On the towers, do the bulges align vertically? If they don't test for run out on all the rotating parts that touch the filament in your extruder. If they do it would cause uneven extrusion speeds and somewhat random location bulges.
Check the runout of all the v track wheels. Both radially and axially. If any have a large wobble that is a likely source. Check if the banding is a multiple of the circumference of the wheels as an alternate method for quick diagnosis. If a wheel wobbles it should cause the error in the part to occur at a fixed fraction of the rotation. Full, half and third rotations being the most likely. Tri-lobed parts are common because the parts are clamped in three jawed chucks while machining. When the chuck pressure is released the part springs back making three lobes.
Perhaps the layer height being used is not compatible with the hardware. Say each motor step moves up 7 (while numbers for easy concepts) while the layer height you chose is 10. So the first layer it mores to the closest to 10 of 7, the next layer sends it 20, so it moves two steps to 21. 30->28, 40->->42, 50->48. Each layer getting round off position error causing more squish on some layers than others. With the lead screw being a speed reducer this issue may be very small and not a problem, I just haven't calculated it out. If the movement per step is 10 or so times lower than the layer height it probably doesn't matter. If the movement per step is closer to the layer it will.
Obviously clean any debris off the rails and wheels, and inspect them for damage, but a repeating pattern makes that an unlikely source.
Those are my ideas off the top of my head. Good luck.
You should also try Alex Kenis' ball bearing trick. Worked very well for me
I had Z banding on my Ender 3, the problem was flat spots on Z-axis wheels. I replaced all six wheels on Z, and the problems were gone. This is very common reason for banding on Ender 3 style 3D printers.
Also the wheels can be compressed too tight on aluminium extrusions(alignment failure when assembling printer), that causes similar issues. To fix that, align your Z that all wheels have moderate and even pressure.
I have two Ender 5’s and they do not have any measurable end play in the Z steppers. If yours do it’s probably time to replace them.
The linear bearings though have given problems. They get sloppy after a while and it causes the bed to slowly tilt after a move. I think the internal plastic guides degrade.
The other problem is they can get sticky and it caused banding similar to your example or worse. Replacing them fixed the problem. Adding weight to the bed also helps. I lubricate them with light plastic compatible oil and it prevents the sticking.
Anti-backlash nuts help a little but I have seen several videos where they are installed upside down. The bed is heavy enough so backlash isn’t really a problem
Great videos. Thanks.
I tightened my eccentric nuts on both my z rails on my ender 3 classic almost to the point where the machine was moving the gantry without binding, but just. This gave me a mirror finish. I use a spider coupler, an anti-backlash spring on my z rod and I also loosen the z rod nut screws to give the lead some play. I also used test blocks to make sure the gantry rail is trammed to the bed. Voila.
Wait, I'm confused, so you make a video about dual Z-Axis upgrade to get rid of the layer inconsistencies, then at the end of the video you show that the mod is pointless?
???
Top leadscrew bracket / stabilizer with bearing fixed my z banding problems on an old Ender 3 Pro. Nowadays newer machines mostly already come with one.
A blood sacrifice to the dark gods of old has always helped me out with any kind of irregularities in my prints. I also used a little bit of marine grease on my screws when I was having a little bit of an issue and that helped me a lot.
My Ender 3 has pretty bad z-banding. I recently heard that the brass bushing that holds the screw to the carriage should be loosened by a whole two turns. I did that and it helped more than I even expected. I checked the printer and noticed that the binding comes from the lead screw not being vertically aligned with the top. So I ordered a flex coupling (5x8mm) and will add a shim between the motor and the frame to fix that. It should be enough to bring it back to the best it can be.
I noticed the same thing. Essentially the same fix for me, but with the ball bearing hack as well. Great results. It's honestly this kind if fix which is just a little bit of knowledge and 5¢ of parts demonstrates the issue with Creality.
for leadscrews, IMO the best way is to buy quality steppers with good thrust springs, buy leadscrews that are not bent, use quality anti backlash lead nuts, and don't constrain the top of the leadscrews (overconstraining your motion assembly leads to all sorts of issues). I think people are generally too quick to change to belts. Maybe because the stock creality setup has so many issues, maybe because new hotness, but I think good hardware can also be a way to go, even if you want to do faster z travel (I mean, we have klipper now right? Turning the steppers faster is less of a problem...)
IMO the problems you were seeing there aren't leadscrew related. They could be related to the v wheels, or the extruder. Direct drive extruders can have several problems that can lead to moiré patterns left in the print, and that can look like z wobble, depending on print geometry. Two that I know of and have experience with are:
1. Loud stepper drivers can have a bad "cogging" effect when micro stepping, meaning that even though the steps are the same size, the micro steps wont be the same size. Obviously, changing the amount of material extruded in a sine-wave like pattern causes artifacts. I've seen way less of this with silent drivers, and changing to higher quality steppers is reported to help as well.
2. Dual gear steppers have been found to subtly change the amount of movement you get depending on where on each tooth of the gear a particular extrusion happens. I've also seen this, but it was a much more subtle artifact, and it was only obvious at thick line widths. Extruders with helical cut gearing are emerging that sort this problem out, but it can also be mitigated using larger gearsets that engage more gently. Specifically I think you have this problem.
I was having awful z-banding issues on my Longer LK-4. I solved it by going dual Z-steppers and lead screws and a new main board that’s supports independent control of the dual Z steppers. I originally tried to do dual Z steppers without independent control using the OEM main board, but an accidental mis-wiring fried the built-in stepper driver.
Haha the experience of owning an Ender 3. I started noticing very slight color banding on my Ender 3 after installing a second z axis and klipper. Slowing down to stock speeds seem to mostly fix it, but I'm sure further optimizations can too lol.
I once faced this issue, it was a faulty "flexible" coupler that was bend out of shape, so i printed a pair of couplers that solve the issue, then i went for a bunch of iterations to get it just right, and I'm using them since then
Never secure the lead screw at the top and let it wobble. Make sure the wheels/rails on the z axis are secure with zero play. Align the z steppers with the gantry brass nut as vertically plumb as possible. Use PID (tuned) for both the hotend and bed temperature control. Make sure the bed has zero play in the horizontal plane. Use real lead screws and not threaded rods from the hardware. Cheers
great one, thanx
Good video for lead screw based printers, i am struggling with this same problem. I have converted my ender 3 pro to Kevin's belted Z design and also running klipper. I observed that printing at speeds like 180mm/s made the problem much worse and hence I went all the way down to printing at 60mm/s and problem remains but much lower. Can you please advise where else I should be looking? I even lowered the acceleration down from 3000 to 1000 but the problem persists. Any advice would be very helpful 🙏. Thanks in advance from your subscriber.
Hi Michael, An update for you, I managed to fix my Z-banding problem. Firstly I had to tighten my Z-belts till they sounded like a guitar string. Second I loosened the eccentric nut on both sides till the wheels were loose enough to just roll or even slightly slip. Now I tried printing at 60mm and all ok, next I tried 100mm, 150mm and 180mm and no Z-banding at all. Only issue at 180mm is layer shifts on Y obviously because of the mass of a 300mm bed. Thank you once again 😊
If there is z-plane wobble (up/down) would a mounting below the stepper motor pushing the shaft up also fix the loose motor shaft (albeit for a short time)?
Another possibility is using a fixed mounting for the bottom of z-rod shaft and a floating coupler to the motor. The floating coupler is fixed to the z-axis rod and the internals of the coupler to stepper motor are a star shape with the motors shaft converted to the inverse 'star' shaft to go in into the coupler. Thus the motor can move up/down while the rotation is fixed by the 'star' shaft (tolerances would have to be tight to allow the shaft to not move in the x/y plane).
Finally, a solution for a problem I don't have!
Been thinking about this video since watching it and I can't help wondering if some of your banding was from the worn out stepper. And to continue that though, if using that linear bearing earlier would have prevented wear that lead to the banding.
Would love to see these fixes compared to a z belt conversion in a future video
Hey, it may be the Y-axis vibaration. I have a similar linear rail setup with the printermod adapters. A ton of vibration. Same with PETG printed adapters. Im switching to a 3D fused Y-rail kit.
Ok , on my E3v2 , i fitted a belt linked dual stepper drive z axis with thrust bearings on the top of the z axis screws. when installing the flexible coupling i pulled up on it lightly then locked the grub screw so it puts a tiny amount of preload on the thrust bearings. This ensures that all the weight of the x axis carriage is bearing upon the thrust bearings and not the stepper motors. There can be another issue at play here - the thread on the z axis screws , they can be dodgy as well but will usually show up as an artifact once every rotation or one that affects one side more than the other .
I bought some flexible couplers to solve banding, never found the up and down play in steppers to be a problem personally. Shouldn't they stiffen up when the coils are powered on too?
SV06 has "floating" zcrew top mount (ie. top z mount allows lead screw to move in x&y). What do you think of 608z bearing mod to remove play? Thanks
You got a song stuck in my head “here comes the hotstepper”
I wonder if the akasam belted z will help. It will reduce the amount of backlash caused by the lead screw. :)
Does the Z stepper motor move in "full step per pulse" configuration? Because the Zaxis motor is slow and heavily loaded, microstepping is not possible because the motor rotor will almost always be attracted to the nearest magnet, causing some accuracy to be lost. Only real mechanical resolution can solve the problem of uneven layers. I currently use a ballscrew with reduction for a resolution of 0.01 mm per step layers are even and almost invisible.
I had issues with how tight my extruder lever was on the direct drive upgrade from micro swiss, also Z-hop introduced a lot of issues, and speed.
I have a ender 5 plus. I'm seeing what appears to be over/under excruciating. One is under, next is over, repeat. Did a bunch of $stuff$ to troubleshoot this. And the better I got the more of a pattern. As in Z screw pitch, transferring to the print. Which is a FDM printer thing.
Just shows up worse until printer is dialed in. Looking to try different Z screws, and then maybe a belt for Z. Good luck with your problem 👍
What about adding an Old ham Coupler or Oldham Thread?
I'd re-torque\align the frame\bed\belts\etc. and then (re)calibrate the e-steps and mA current to all the motors, to start. During that procedure, find out if the lead screw(s) has\have wobble by rolling it\them on a flat surface (E.G. a cue on a billiard table).
I didn't know\think about the deformation of the bed due to heat. I need to watch that video to see how to test for it and\or if there's anything that can be done about it. Which, in the end, is what I would do after I completed the above steps. Does The Internet (specifically my favorite, Teaching Tech! Hi Michael!) have any answers to my existing dilemma?
There is a file available for a brace for the bottom of the lead screw for the Prusa Mini, but as the carriage for this axis actually rides on encased linear bearings on smooth rods with the lead screw only providing movement and not alignment, I don't see how it would actually do anything. Am I wrong on this?
Could you try out the new WobbleX from Mellow?
You'll never get accuracy with the 2nd option because it allows the motor to rotate in the cage ever so slightly, which in turn has influence on the rod moving less than requested since part of this move is lost on the motor body moving first.
I have had the Z stepper Cage on 2 printers for over 2 months with no negative impact to quality or dimensional accuracy, one printer is in a enclosure with 35-40 degrees ambient temperature. It is technically better that the usual “fix” of allowing the lead screw nuts to float by not having them secured tightly.
I used 5mm Id thrust bearings with a printed spacer instead of the whole printed bracket. Wasn't for banding just to reduce the thrust force on the stepper motor.
I encountered some z-banding on my Bambu X1C but only with one specific color of one manufacturer's ABS. Using a different color from the same manufacturer with the same model/settings did not exhibit the issue. What would cause that?
Hi, Have you tried Tekti3D 's Anti Z-Wobble Nut with Magnets and bearing balls?
Could you investigate an idea I had that is a bit out of my league as far as coding? I think the TMC drivers with stall guard could be used for resonance testing without any additional hardware. I made a post on the Klipper forum called “Sensorless Accelerometer with TMC stepper drivers?“ I started digging into the data sheet and I think the data points are available but I don’t know what to do with them.
Even if this only works poorly it would be an improvement over no resonance testing and if a bit of code could unlock resonance testing without an ADXL345 that seems like it would be a game changer to me.
Eventually I’ll circle back to this on my own but it’s been almost a year since I had the idea and I’ve only made it as far as a feasibility check.
freeze frame at 5:16 and check out the X banding there. can you do a video on this?
As im thinking about it wouldnt the Z wobble be a bed issue? Z can go striaght up, but if the bed isnt slinging back and for to the same spot everytime you'll get Z banding as the bed moves 10 units one time, 12 units another. Perhaps getting rid of the play in the bed? Or in a box style printer it would be the x or y. Im sure Z issues add to it but since they've been addressed it could be the other axis.
That is a good assumption, but the bed flinging back and forth doesn't cause this problem (Z-banding/Z-wobble). The problem that a moving bed introduces is ghosting. Lots of ghosting compared to a coreXY machine.
Michael, how does one solve the issue shown on the Ender 3?
Any ideas on a fix if I'm experiencing this issue on a delta printer?
Try replacing the feed nut with a plastic one. Ready-made nuts from POM are sold in online stores. But you can also print your own. Such a nut does not have any kind of backlash because it is printed with a slight interference.
There is not much of backlash on Z axis nut, becouse gantry weight push it on one side of thread .To minimalize "springiness" of spring washer inside steeper motor and flex of coupler I would try to put sperate bearing block after coupler, like in cnc mills.
Pity that needs didn't help in this case, but a Thrust bearing is definitely something worth adding to the Z axis, even if just to extend the life of the stepper(s).. one of those things that makes me wonder why printers aren't just made with 🤔
one test you can do is print something like your test tower with diameter X then print the same test tower with for example diameter X*2. point being to make the extruder extrude more filament per layer. on one tower than the other. sometimes it's something goofy going on with the extruder. you should see the pattern occuring more or less frequently along the Z axis if this is the case.
Actually I found my Z banding issue. The top brackets were off. Slightly loosened them and they moved right into place. Perfect print. Still got the Y-axis vibration but gonna solve that with a high quality kit
When I had my orignal ender 3 v2 (now i'm using Ender 3 v2 coreYX) I found that the this issue came from the miss alignment of the Screw Nuts T8. If you look carefully from left side of the printer the extruder stepper motor and screw nut holding plate you will find that this holding plate isn't bend plate exactly at 90° (little bit less) and if you remove the Screw on the T8 Nuts you will also find that usually one holding screw has more washer then the other (to compensate the bend plate). So If you play little bit with those washers by adding or removing them you can find the sweet spot to compensate correctly the plate angle and that was my solution to reduce Z banding by finding the route cause of if. Observation!!! if you do this fix that Z banding will be reduce and the Z axis will be very very smooth! As a result of this you may need to always lower the Z axis before turning off the Z stepper in order too prevent any fall (when I said the Rod will be very smooth that mean very smooth :D)
I installed #1 on my Ender 3 v2 because
My favourite Z-Banding fix is Oldham Coupler. But if you want to know what really works, only thing which works is Stepper Motor with Integrated Lead Screw.
Interesting .. but wow , it's a big tower , is the size of 30x30 mandatory to get a good test ?
Problem could be also hidden in bad quallity dual gear extruder, @MirageC explained that problem really well.
I would suspect the lead screw itself has an issue. When they are first installed they work great, but they wear out over time. One thing to do is install anti-backlash nuts on each lead screw. I did this on my Ender 3 v2 and it helped a lot. Another thing to consider is installing ball screws.
those are rather expensive and the cheap ones can wobble too. MirageC did a video on that but the only thing is you can't fit them onto the shaft of a typical stepper
@@nathan22211 I had not seen that video. It is very informative and his solution for the ball screw wobble is really neat. Like he said though it is just a band-aid and is not as good as a high quality ball screw. That being said the ball screw did fix his z banding issue after his ball screw fix was engineered and put in place.
I use a floating z axis on my cartesian printer, no direct attachment at all. The gantry just rests on a flat surface allowing it to remain unaffected by the leadscrews.
You forgot Oldham couplings.. they solved so many issues I had!!!
i have no doubt these work. but considering the effort needed to install these, the major concern is longevity of the part. i think most 3d printing people do not have experience with PETG--i think it should be mentioned to not even bother trying this in PLA because the part will eventually completely fail from creep or worse within a few months--my guess is the part that mounts the stepper to the vertical post will be the first to go. my favorite mod for bent leadscrew is HevORT's implementation of the z-wobble nut (a really clever implementation of the oldham coupling, with the advantage of being detachable with zero effort) and a $2 metal stepper motor mount from aliexpress.
My biggest change I had was adjusting pid tune till I got it to stay right on target.
On mine every other layer stuck out just a little bit.
One out,one in,one out,one in.
So did you find what was causing it? My next try would be swapping for another extruder in case it's induced by misaligned gears
Epic fail. However, very creative and effective ways for those two guys to fix the problem with their specific printer.
I have a specific layer about an inch up that is often thicker, like an elephant foot but higher. No idea why yet, and it only affects one printer, but the other.
Why the gap between the stepper motor and the lead screw? 🤔🤔 It was mentioned for both methods.
Hi Michael, thanks for giving us all an insight for "fixes" to the "Z wobble", I was wondering why a smear of silicone grease wasn't added to the thrust bearings?
Forgetting to add that to the 6 dang bearings on the giant printer build at work I did was one thing that made me face palm at my own forgetfulness after the fact...
They just work so smoothly without it that it's easy to forget, tho I definitely would advise against letting it be for service life sake.
I wonder how oldham coupling would compare to these DIY solutions.
On my Artillery X1 i was getting z-banding. I ended up getting new couplers that flex and now it's gone.
complicated ? You simply need a coupler which allows for some radial movement. You can just buy one. The leadscrew is not supposed to be ridig it´s simply allows a up and down movement. The carriage with the wheels is "leading". You need to decouple both from eatch other, otherwise your system will be overdetermined.
I went for belted Z, which fixed all my z banding issues
Got link for the bearings?
I actually added a worm gear and mount on my z axis, then increased steps to match the gearing. It's much better now, but still never perfect.
Update, I've added a second z screw with worm gear and removed the top constraints from both screws. I cannot find any z wobble on any of my prints anymore. I'm still fighting VFAs but hopefully a new motherboard with 2209s will help clear those up as well.
Z banding is usually a result of a rubbish extruder or Z badly tuned PID temps on bed and hotend. Rarely is it leadscrews esp as the Z axis are normally constrained either by extrusions with wheels or linear rails.
imho those are extrusion\filament issue and not Z wobble. I am running kevinakasam`s betled z on my ender 3 pro and it simply ruled out most of irregularities, I have crappy bmg extruder however replacing all gears helped still I see some extrusion variation. Unable measure tiny missalignments
unouts\backlash I tried to rule out filament width. +-0.05mm isn't enough accurate... on the prusament`s pla I see far better results thanks to +-0.01 variation during prints. unfortunately it is on a pricy side, so it is for a accurate prints while mass production goes on regular pla
#2 would work allot like a oldham coupler. i think there are even 3 printable olhams out there
A deep groove ball bearing can take a decent amount of axial load. Using them in a 3D printer, this rated load is well above anything you can load them with. I recommend the 608zz for any application in a 3D printer (8mm ID x 22mm OD x 7mm thick). Just put a spacer in place to put the axial load on the center race and not the outer race.
For lead screw wobble, check out Oldham couplings. They are a 3 piece design with the pieces connected with dovtail joints set at right angle from each other. This allows sliding in X/Y but no play in Z. I found them from this video th-cam.com/video/RXgwOikiBdg/w-d-xo.html
Agreed on the deep groove ball bearings. With the loads we're talking about here, they're more than enough. I do accept that thrust bearings are the 'correct' way to isolate the load from the motor, it's just that it's overkill.
just get rid of the brass nut and install pom, you will notice the difference while installing - pom is tight. 2$ parts which are machined can't be any good. also resin printers use pom nuts, if they work for those they will for fdm too which has much less z movement. also those use motors with integrated lead screws. then add a z-sync mod to keep the x-axis centered on both sides. next upgrade would be linear rails. just copy resin printers, those work with much more precision and flawless z-axis under much bigger forces. and before you start upgrading all of this, consider selling the old printer and buy a new one :)
Not using a lead screw and going dual belt drive with rails is the ultimate fix. Not the cheapest fix on the list but it's a one time thing and your Z problems are gone. Depends on your budget. Really not much Ender parts left on mine aside from the frame and bed, might as well built one from scratch. It's now a DD-IDEX with all rails and belts.
what about the belted design?
Lead screw wobble, Z-axis bearings, Z-axis tramming, extruder gears and teeth, extrusion pressure, PID tuning on the hotend, filament humidity, filament diameter consistency, ambient temp fluctuation... and I'm sure there are some other factors. Hard to track down!