Should you use a Reverse Bowden?
ฝัง
- เผยแพร่เมื่อ 25 ส.ค. 2022
- You've heard of Bowden 3D Printers, but did you know you can set up a Reverse Bowden, too - and make your direct-drive printer more reliable in the process?
Thank you to Anker and their 757 PowerHouse for sponsoring this video! Order on Amazon: ankerfast.club/3p2WcQy
Order on anker.com: ankerfast.club/3JAV5B9
#PowerStation #AnkerPowerHouse #Offgrid
Read the article to this video here:
toms3d.org/2022/09/06/should-...
Relevant products
Prusa MK3 (S+) go.toms3d.org/Prusa
Prusament go.toms3d.org/Prusament
Printed parts www.printables.com/model/2715...
Product links are affiliate links - I may earn a commission on qualifying purchases (at no extra cost to you)
🎥 All my video gear toms3d.org/my-gear
I use Epidemic Sound, sign up for a 30-day free trial here share.epidemicsound.com/MadeWi...
🎧 Check out the Meltzone Podcast (with CNC Kitchen)! / @themeltzone
👐 Enjoying the videos? Support my work on Patreon! / toms3dp - วิทยาศาสตร์และเทคโนโลยี
For me, the mod with the biggest quality jump was making a low-friction spool holder, I made one of the many skateboard bearing based spool holders on Thingiverse. It made my layer lines noticeably more consistent. Though the reverse Boden could be useful to me since I have the spool holder screwed to the rafters 4' above the printer.
So Anker can sponsor a video on a 3D printing channel, but won’t send a review unit of their 3D printer to the same channel. Interesting.
Because Thom is one of the few creators with a clear sponsored review policy/contract. They probably want an advertisement disguised as a review.
@@Deaner3D I think it's not even that. Not sending the printer to anyone but 2 channels (one of which doesn't cover 3D printers anyway) means that they really don't want reviewers to put their speed claims to test, or look under the hood.
Same with Prusa XL, the preorders are on at the moment with no reviews in sight - but atleast we know that 3D printing channels will receive review units at some point (based on Prusa's previous record).
Anyway good for Tom, his content is good and deserves sponsorships - just a peculiar move from Anker.
@@Deaner3D Like the burned in ad, correct?
Bad content to ad ratio, too!
@@TheCyberSpidey Prusa hasn't even finalized the BOM because of supply chain issues. They can't send out a review sample if the release version is very different
I prefer to us a PTFE tube with 3mm inner diameter for the reverse bowden to get less friction.
This is what is specced by Voron 2.4R2 for its reverse bowden.
Same. I ended up changing from the 2mm ID after any kinks in the filament were causing too much drag.
The drybox scenario is what i do with my normal bowden setup. Interestingly, the bowden tube fit perfectly in the little hole of the drybox and ensures the the filament doesn't rub away the enclosure hole. The friction of the hole and the bowden tube is perfectly enough to keep the tube in place. On the other side, the tube pushes against the extrude inlet and stabilizes the position by itself. This allows me to have clean filament fed and "going around corners" from the drybox placement without any weird kinking and pulling of the filament at odd angles. On retractions, the bowden tube pushes away a little from the extruder, so the filament doesn't get pushed back through the whole tube back into the drybox. This also allows for easy pulling away and out for filament changing. Pulling friction through two tubes is not noticable to me, retraction only has friction through one tube as before.
In that way, it is not a reverse bowden setup as you showed, but similar enough when you just look at it.
Thomas, thanks for all of your informative videos. One other advantage of a reverse Bowden, I have converted to a direct drive and wanted to continue to use my Smart Filament Sensor without adding the sensor to the print head. Using a reverse Bowden allows me to place the sensor on the printer frame and off of the moving part of the hotend.
Been using one for ten years on my Hypercube. I have the filament spools mounted on the side of the printer, with a little funnel like feeder with a filament out switch on it, where a 4mm PFTA tube plugs into, and another adapter on the top of the Titan direct drive extruder that the other end plugs into. Has always worked flawlessly.
Tom - If you figure out the issue causing the surface imperfection, please let us know. I have the exact same issue and haven't been able to figure it out.
I found this video perfect, I printed a Prusa spool holder and mounted it in my Anker M5C to get rid of the idiotic and weak stock setup and I was running with only a 1” piece of ptfe that I bellmouthed to help guide the filament into the direct-drive extruder. The filament roll was flopping around a bit and tugging but like he showed, it didn’t cause any issues and now my cardboard spools roll smoother as well.
I have always wondered if the force would be enough to deflect, this is interesting for sure! From the sides maybe, but like you showed, I have not seen a degradation in print quality by having my spools above and forward of my printers.
Great video, easy to follow, described the problem and shows the solution, and is super easy to do.
I made my own printer enclosure and the filament feeds in from the roof, and I came to the same conclusion and found benefit from using PTFE to take the filament pullback force out. It worked whether I had the standard Ender3 extruder/bowden setup or an aftermarket direct extruder, and in neither case did I use a fiitting at the extruder drive - the teflon tube just goes from being fixed at the top to loose at the entry into the extruder gear. That makes it easier to thread the filament, and the tube still does its job of preventing the printer from trying to pull itself back up the filament. The PTFE is slippery enough that the extruder motor never notices the little 'hop' the PTFE does (from extrusion/retraction cycles) and as the tube is fixed to the same enclosure the printer is mounted in there's no force transmitted to the printer frame. And you get a quick visual confirmation that the retractions are happening.
Here's an idea for a future video though if you feel like getting hugely frustrated: Minimalist filament 'splicers.' I found some on Printables that can be printed, then I found a commercial metal unit on a certain Chinese multi-store-market site. But you need good eyesight and manual dexterity for these fiddly little gizmos and due to age and medical reasons I have neither. I still managed to actually make a few splices in PLA with the three units I tried but results are a bit random and sketchy and prone to breakage. Cheers, @prawnheads1
Don't use 2mm ID, use 3mm ID, you really don't want that extra drag in a reverse bowden.
I did the reverse Bowden with my Monoprice Maker Ultimate. Made a big difference in consistency.
Reverse Bowden? You mean a filament guide tube? Been using one for years, didn't know it had a fancy name! Great video again!
Thanks for your Video.
I am printing a lot ABS lately and always had my Fillament outside my Tent in my dry box and wasn't considering that as a problem.
A week back I didn't need my Fillament dryed an had the spool on top of my Printer and was surprised by better Prints. At that time I wasn't exactly sure why but after this Video it all makes sense.
Honestly my steup with the tent on the ground and the dry box on the Table is kind of getto but I was surprised that it Realy made a visual difference.
Interesting idea. Ironically i do this as well from my dry boxes to my printers. I do want to add you might have missed sone additional forces. Restriction through a bowden does provide resistance and possibly worse then an open spool. Depending on the length of the reverse bowden (or as i call it a feed tube since it doesnt really work like a bowden imo). Also if that add on tube has any coils or bends in it that is going to add to drag. I got all my Teflon tube from a 3d supply store and it came from a spool. So it was already coiled. I have found this to add a ton of drag so straightening the tube is advised.
ive been doing this for years and it lets my Direct drive pull evenly on the spool at all times and its not those sudden hard pulls that happens with travel movement. A must have for large printers.
never understood how is it not included in prusa kit by default
Perfect timing!! I just bought a filament dryer for my PETG spools and was trying to figure out how to feed it to my mk3. Great vid!
I did this to my CR-10 Direct Drive and it definitely helps!
Reverse bowden actually made a big difference to my prints when using 3kg spools on my ender 5. The cartisan printer carrige is more susceptible to issues due to drag and the drag on a 3kg spool is much higher than a 1kg one. When I switched to a 3kg spool my failure rate went up to about 30% from about 10%, and with the reverse bowden it went back down to below 10%. The main reasons for failure being under extruded layers or jammed filament.
When I switch from direct to Bowden and back I started using the tube on the direct extruder. Found that it worked pretty good so I just left it that way.
Im 100 percent agree that the tube is IMPORTANT!
I have it on both of my printers (both direct drive) and this drastically improved the print quality and reliability!
This was a super helpful breakdown - thank you! My space is very limited and I need my filament to sit next to my Prusa 3 instead of on top. Thanks to this video, I know exactly how to swirl my space, and why!
Fascinating stuff, I already printed a modified filament sensor cover for my Prusa Mk3 which I added a bowden tube holder, to help feed flexible filament from sitting in a food dehydrator, which I also added a bowden tube holder to.
I added one to my Snapmaker 2. Was the easiest way to keep constant tension and stop it from slacking off the spool whenever the print ended and the head rose to the top of the Z-Axis. I use it a lot for TPU on my other printers, too, just to give it an easier path so it's not tugging straight down on the spool.
Also great for run-out detection based on actual movement of filament (vs. the ones that just detect a break). Without it, the movement of the head makes it harder to detect if actual filament is being used.
On travel moves and with not so good spools the drag is quite substantial. Also brittle filaments can be guided. Qidi x max is an example where this addition makes sense. With really cheap prototype filaments (owl) it's also a safety mechanism because it gets stuck with bigger diameter inside the tube and not inside the extruder or hotend (especially with mosquito or dragon style hotends)
I have a spoolholder/storage for 15 spools at a time but my rollers aren't optimal, so my drag is a lot higher than on most normal holders
Reverse bowden is a must especially at higher print speeds
Hey Thomas, that pattern you’re seeing is most likely the infamous issue 602, and is most likely related to the hobbed dual drive gears. The teeth from the gears have a bit of backlash, which causes the filament to not be pushed down perfectly uniformly. That, in combination with the lack of rigidity in the frame.
Running the filament from your drybox through a teflon tube to your direct printhead also keeps the dust off. I use 3/5 mm tubes (not so floppy as 2/4 and less friction). Excellent video, Thomas! I'd still recommend a dust filter on top of the direct printhead, although the 0.6 mm and up nozzles are more forgiving when it comes to dust particles.
We stuck a 5kg roll of filament in a dry box under a table, then ran a 4mmOD-3mmID PTFE tube up to the Prusas. Never had to change or deal with filament problems for several months (in a free-use university maker-space)!
I've been using reverse bowden for a while! For the reason of having my filament mounted lower than the printhead.
Yet another nice video and what a coincidence. I was thinking about exactly this yesterday for my Ender 3 S1!
Normally I'd be annoyed by such a long ad, but that power brick thing actually looks pretty awesome.
@Thomas, you may want to double-check your Prusa z-axis assembly. On the three Prusas (MK3) I have access to, when I apply a reasonable amount of downwards force to the top of the extruder stepper (a few pounds), the extruder deflection is imperceptible - much less than what this video shows.
Great info. Thank you! Do you have a link to the small 3D printed parts?
I have a bowden hotend, and i added a bowden tube from the extruder to my filament box/dryer to protect it from dust and humidity. Since I installed it I had 0 clogs or problems at all.
i have been using it like that since i switched to a direct drive setup, because the filament spool sits inside a drybox on the side of the printer.
without a bowdentube the printhead would pull on that every time the x axis moves...
fore sure, I have been adding that to every printer I have ever touched for years. It does really help.
I used a 'reverse bowden' setup on my custom CoreXY printer (direct drive) that has a canopy so it's totally enclosed. It worked but would often result in the extruder jamming with larger prints. After unsuccessfully trying different PTFE tube sizes, the final solution was to have a connector at the filament end that is free to rotate 360 degrees so that the bowden tube is better able to release tension and not grip the filament at extreme positions.
do you have the STL of this
@@Zzafari7 The connector is an off the shelf product: P NSF-51 tube fitting adapter with 4mm diameter hole, BSPT thread, as used for water systems. The important part of it (other than fitting the PTFE tube) is that it allows rotation of the tube once fitted. I did create a CAD model for the upright that houses it, but it's nothing special - looks like a square building with a hole down the center of it (top threaded for the tube fitting adapter) and some mounting holes as I used 2020/2040 aluminum profiles.
Does anyone have a link to the reverse bowden parts? I like the way it mounts but I'm not having any luck finding it.
with a perfect spool its of negligable value, if the spool is unbalanced or the filamant gets a little stuck. I found got a different mesh on spools that rocked back at certain points on the spoolholder.
We use a similar setup at work. The direct pull with 2.85mm filament would leave pretty bad artifacts when the spool would get low. Added the bowden, put the spool in an easier location to access and now the printers run much better.
Agreed, the reverse bowden is a necessary upgrade. However, filament retraction will separate poorly coupled tube ends due to the bowden tube/filament internal friction. Rapid retracts exacerbate the tube decoupling nearest the extruder. I've had to add a PTFE fitting on top of my Ender 5 with the direct drive extruder conversion.
Hey Thomas!
Design up a way to always have slack between the DD printhead and the filament roll.
I have always wished there was a way to somehow motorize/other, the filament roll to always have some slack. On fast retractions/movements sometimes the filament roll will wind and unwind (roll out/roll in) which ends up putting bad pressures on the extruder.
I own a 3d Printing retail business/farm/service and this is something I have always thought about. I ended up making all filament roll Holders with a more Clutch style assembly. Bearings roll too smoothly etc.
Thank you for your content!
I actually was wondering since a while if it would be good to have a synced bowden motor with an extra direct Extruder Motor. So nothing could go wrong like this?
You'll need that powerhouse come winter... Great video!
Reverse bowden was great just for filament guiding on my Ender 3 knockoff, and it's even more critical now that I'm using both an enclosure and drying box.
i have them same pattens on my ptints did u fix it if so how ? thankx
ive been doing this for a while from my multi-spool dry box to the filament sensor on my ender 3s1. it works a treat... just have to make sure the filament unrolls nicely from the spool or we have a bad day
I have a modified Ender 5 (Direct Drive) that uses 2 BMG Extruders. One is for DD itself and one is attached to the frame to help feeding filament. It works pretty well and I have some extra time to add a new spool to the feeding system without any kind of issues in the process.
That's nifty! I tried adding a new filament with the remote bowden setup and because that creates a break in the filament it couldn't retract the old filament in the PTFE so I had horrible over-extrusion and stringing until all of the old filament had been pushed through. Not so much of an issue with a direct extruder but I can see that using both would minimise the amount of unretractable filament.
Could we avoid the need for a bowden altogether if the spool holder was motorized in sync with the extruder, to unspool the filament at the same rate that the extruder/toolhead is asking for it?
I have an hemera modded ender 3 v2 and Ive often wondered if I could do exactly this if I was to take my spool holder off the top and have in on the ground... Question answered. Thnaks heaps bud 👍
does anyone know where the best info or troubleshooting can be found??? I can not get my A10 32bit upgrade to work 100% My extruder shuts down after 10mins??? tried open case with a Fan, I'm not sure it's heat related now as that made no difference....?
I've had a reverse bowden for years because 1) Repbox setup that is in a wacky location. 2) I use a Mosaic Palette which not only does it's own reverse bowden but a mount of some sort was needed on the extruder to hold it (like the slip on that Tom used) and that didn't have to only be used with the Palette... so
Haven't thought about that too much but always interesting to see these experiments. I tried to have my spools at an ideal " drag roll" ratio. Meaning it is very easy to unspool but they dont get into the motion of doin that by themself. They did before I removed the bearings. All working nice but I have those same lines in that light direction.
I told my self that this is how it looks when you build something from many layers.
Still considering to go to .6 nozzles :)
Well, and now check and calculate the drag...
It depends on filament a lot how much drag you will get but with some filaments it added enough drag with the reverse bowden that the direct-drive was getting into clicking, with it removed, the clicking was gone again.
Another point for drag is of course a filament-sensor (of the cheap kind with just a switch) which all adds up to the path. For now I go with normal PETG, PLA and ABS and especially flex without the bowden on my printers but with a drybox and those filaments I will probably go there again.
I was thinking, why not get 3mm bowden for reverse? Same positive factors but not soo much drag added ?
I've used a "reverse bowden" for a long time as a filament guide. Very handy. I didn't notice any change in print quality though.
Please share links with me how to set bowden tube to Eibos Cyclopse dryer. He touched on it but would like to see a bit more detail and instructions. I am a bit slow.
Shouldn't the weight of the spool turning on the smaller diameter spoolholder be the main cause of the issue? Because of friction?
Someone knows what's the name of the artifact shown at minute 6:05? I have the same issue but I have no idea how to fix it
Did it years ago.
Can I put a link to it?
It shows a Mechanism to adjust for retraction when using this type of feed.
Hey! Thanks for the video! Do you have a link to the printed parts? Looking to improve the filament path as I print directly from a dry box. Thank you again!
I've just uploaded the files to Printables! www.printables.com/model/271586-prusa-mk3s-reverse-bowden-mounts
@@MadeWithLayers much appreciated! Thank you for the quality content 👍
but how could you fix those ripples, got htem myself and cant find a thing ot that
Neat, Thanks Thomas!
The Prusa Mk3s with multi-material upgrade already uses a both a normal and a reverse bowden system. It uses a normal bowden system to load filament to the toolhead, and after the toolhead detects the filament, it takes over and the filament loader/selector disengages. The system then acts as a reverse bowden. It actually works pretty well in my experience.
Where do we find those parts you showed in the video?
Hi Thomas,
the inconsistent extrusion that you showed on the two pink parts is a problem that I have aswell on my Prusa. Were you able to solve it otherwise?
Also thank you for this video. Very informative as always!
I think MihaiDesigns developed a single-wall print test which allows you to determine the periodicity and axis-alignment of any print unevenness. According to this test, for him, the periodicity points to the geartrain that meshes the two extrusion gears together, if i remember right. He has been developing his own toolhead and obviously it's overengineered to solve entirely different usecases, so i don't know if there is a simple one-step solution known.
For reverse bowden it makes sense to use 4mm OD 3mm ID tube instead of 2mm ID that Thomas recommends. Reverse bowden does not need the filament constrained as much as regular bowden and the looser internal diameter reduces friction thus needs less pulling force by the extruder.
I'm surprised it's not more common, as I've been running the "reverse bowden" on my printer for years.
It solves some big problems, like:
It'll eliminate most of the pulling force on the extruder(A common problem with big spools).
And I've never had a problem with tangled filament since.
how does it eliminate the force on the extruder? Your filament is still attached to the extruder, and the extruder still has to pull the filament off the spool?
@@MassisPipes It's not the force of the filament getting pulled by the extruder motor you eliminate, it's the jerking on the filament spool when the the extruder moves.
Some printers are more affected then others.
Eg.: if you have a side mounted spool, and your hotend is printing close to the spool, then the hotend moves away from the spool to the other side, that move jerks/drag the hotend and spool.
@@RandomloserDK aah, that makes sense. It also explains why I don't need it, since my machine is a bedslinger with the spool centrally above the X-gantry, so those distance differences are minimal.
Tom, can you please share with me the STL for the bowden tube clip and the revised extruder cover? I want to use the mk3 inside of a Ikea Lack enclosure, but obviously the spool holder will not fit. I have the Prusa Mini on top, so I want to put the filament inside on rollers, and use this setup. PLEASE :)
www.printables.com/de/model/271586-prusa-mk3s-reverse-bowden-mounts
Hi Tom, it would be very interesting to see you trouble shoot the weird extrusion pattern
Now I need two of them to use as UPS for my freezer and refrigerator.
Im sure you know this now, but that visual stuff you were trying to get rid of is prusa 602 and is caused by the bondtech drive gear being eccentric due to manufacturing tolerances
I know this is an old video but if by any chance you see this Tom, I have exactly the same print quality as the parts you showed in this video and have been killing myself trying to fix it. Did you end up resolving this issue and if so can you point me towards a video where you or someone explains the fix you used?
What dry box do people recommend?
i have been using a teflon tube from my dry box to my printer for years, just for dust and moisture protection. since i have been doing that i havent experienced any clogged nozzles. (but i also clean my nozzles now and then)
Me too. I made my own dry box which has three output couplers to which I connect the PTFE tube, which goes to my direct-drive hotend.
I have been using this because I did not want the lazer runout sensor on my print head. my flashforge creator had this stock.
had a rbt setup with my ikea enclusure mk3 - removed it - added way too much drag and did not improve anything...
Pushing filament through a boden tube and pulling filament through a boden tube are very different. Pulling is more efficient. You would have no trouble using a flexible or softer filament when pulling it through a "reverse" boden tube, but pushing the same filament might not work at all, or work poorly. Even with a harder filament it is also true, but perhaps to a lesser degree.
Nice i did something simlar but i will improve after seeing this
My extruder cover looks different than yours, did you print a special cover for this?
I've had a reverse bowden tube for ages, just because I had tubing left over when I converted my printed to direct drive and thought it looked "naked" without it!
Where did you get the model?
I tried something like that for a ewhile, and it negatively impacted the quality of the print, I think there was too much friction. I should revisit but set it up properly....
What about routing bare filament over the back over an empty spool?
Regarding reverse Bowden tube for keeping moisture OUT. Has anyone tested for TUBES sucking moisture (condensation ) from outside the Tube to inside the tube and onto the Filament , WET TUBE SYNDROME @TY This seems more apt to happen than keeping moisture out.
I can't say I've ever had any issues but I've only been in the 3D printing game for almost 2 years now. I have an i3 Clone and don't have those elements in the prints. I believe they are caused by the stepper motors and their harmonics dealing with the steps themselves. The only artifacts I get are some slight ringing. I'll keep this in mind but for now I like my setup.
i use a closed loop for nylon printing using the mmu2 m6 pc extruder cover
Interesting ! I've been using Reverse Bowden intuitively when going from Bowden to Direct Feed. Though, my prints don't show the artifacts yours do...
Using 25k spools on my custom modified Ender 5 Plus systems at work would actually lift/bend the x gantry on a full spool and is the reason why I ended up swapping it to a regular bowden setup so the stresses are on the frame instead (with the added benefit of being able to feed from the bottom) but I have been wondering if a reverse bowden would help with this as well.
consider adding a 2nd feeder extruder that mirrors the primary extruder, near the spool
Have you ever considered making a test about Silica Gel in DIY drybox vs. filament dryers? You have a video about cooking filament to dry it out, but multiple sites suggest that leaving filament in boxes with silica gel for more than 24hours would render the same result. Thougts on that?
I've been using this for years, but mostly to avoid the filament unspooling too quickly and tangle.
I use an older reverse config on the office MK3S+. I can then position a spool on a bearing-type spool rack behind the printer and thread in the filament. I was never a fan of Prusa's "tug the filament right against the frame" setup.
Instead of a washer for the dryer box, i had a spare push-on fitting for a bowden tube that threaded into the hole perfectly because coincidentally the hole matched the minor diameter of the threads on the fitting
The even more sophisticated method is, if you use a second (bowden style) extruder together with the direct drive extruder, simultaneously. I call it twin-extruder and I use it on every big machine I have. The bowden extruder has an independent mounting from the printer frame, so the filament dragging forces are not affecting the frame at all (think of 8kg spools...). Another advantage is, that if the two extruders are working together, the bowden extruder can help out the direct drive one if it would come out of juice, by pushing the filament into the gears. Hereby you can gain ~ 20 to 40% more flow compared to only one (direct) extruder.
I never imagined someone would use a direct drive extruder without a reverse Bowden. But then my printer's spool mount is sideways so it really is necessary.
You've presented some motivations in favor of reverse Bowden I hadn't considered before. Personally, I dislike them because they negate one of the biggest convenience improvements of direct drive: not having to load and unload filament through a Bowden tube. I think some of the benefits can be retained by using one or more pulleys with bearings (specially designed not to drop the filament under loss of tension, using some tricks with TPU) rather than Bowden tube.
that is like a tiny inconvenience
@@duality4y If it doesn't bother you, great. 😁
I only fix the remote end of the tube in my setup - that way I feed the filament through the PTFE, then can grab the end and just insert it into the extruder motor, really simple and lt it bob up and down with the retraction cycles. Has worked for me like this for nearly two years, works with any setup. Hope this helps.
I was just thinking about this last night. I felt like it would be a bit smoother.
I have a dry box (my own design with silica) and reverse Bowden on all my printers.
it also keeps the filament dry on its way from the spool to the hotend, especially when you print out of a dry box.