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Folgertech Prusa i3 2020 Y-Axis Upgrade (Openbuilds V-Slot Rail System)

by sonnylowe Jan 19, 2016
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Hi Sonny, Thanks for your design, I am going to upgrade my Y-axis and probably x axis based on your designs.

I saw the link to an on-shape design but couldn't find anything through link or search. Do you still have it uploaded anywhere?


I can't find the link I provided, can you paste it here...it will help me find the file (if I still have it!?!?).


I was wondering what are the cut lengths of the 2020 extrusions for the frame? I want to buy 2020 extrusion and cut them myself instead of ordering the kit from Folger Tech. I looked all over the internet and I can't seem to find the individual extrusion lengths.

Thank you for your time :)

Lower Frame:
Front and Back Rails (20x20x375)
Side Rails (20x20x365)

Vertical Rails (20x20x295)

Top Rail (20x20x375)

Hope that helps,

Where are the Z motors?

They are mounted in the same location as the stock setup and use the stock hardware.

Hope that helps,

Sunny, are the openbuilds pulleys and belts different from the ones shipped with the folger tech kit?

They are all GT2 style belts and pulleys, I can't remember off hand which ones I reused if any, but you can check the parts list and compare it to what you already.

Hope that helps,

Wow. From the first week I had my printer, I had planned on installing this upgrade. At 3 months, I finally got around to installing it. I cannot believe the difference. I didn't realize how much my y axis was causing issues in my prints, because after installing, I got a perfect first layer on the first print. More than that, the y axis is near dead silent now. It's removed all doubt I had about proceeding with the x axis upgrade. Thank you!

So glad to hear you are pleased with the upgrade...enjoy :-)


Can you please elaborate on which 6mm spacers you’re talking about in the BOM? I ordered these...good enough? http://openbuildspartstore.com/aluminum-spacers/

Thanks. I just noticed that 6mm spacers are included in the V-slot gantry set I bought here: http://openbuildspartstore.com/v-slot-gantry-set/ I didn't see the spacers in any of your photos. Is that what they're for?

Also, OpenBuilds didn't have the bearings. I bought some VXB ones off Amazon instead. Hopefully they're nice & smooth.

Thanks for the design!

Sorry, I might need to update the photos and add some info!?!?

I was using the printed bed mounts but found them to flimsy and weak. So I now use the original aluminum plate that came with the kit. There is a PDF that shows the hole pattern for the four holes you need to drill into the ALM Plate. The 6mm spacer go between the ALM mounting plate and the gantry plate. If you need it I can take a photos of my current setup and post them.

As far as bearings, the VXB should be of comparable quality as long as they are at least a ABEC-1 series.

Hmmm...I might be confused. Are you saying that this was too flimsy? https://www.thingiverse.com/thing:1266958

I'd love to see some pictures if you have some time. Thanks!

Printer bed support

No, the ones I had designed were too flimsy to hold the heated bed alone, if you added the ALM bed to the printed mounts like QuadBert they would have been fine. My setup simply uses the spacer and no printed mount, either way will provide a sturdy printing surface.

I'll take some photos and post them as soon as i have a chance.

Awesome, thanks!

Another thing.. It seems we need self tapping M6 to go in on the ends of the rail. The mounts that make use of the slots can use the Folgertech nuts no problem but on the ends of the rail the M5's do not thread in as it is too small. Did you use M6s ?

1 for the motor mount and 2 for the front holders that contain the flanged bearings.

They should be M5, if the hole is too big there is a problem. Did you buy actual Openbuilds rail, or some other brand!?!?

Probably another brand. dimension wise it is IDENTICAL to the OpenBuilds rail. just the center diameter is slightly larger.. No worries I tapped a 6mm and am good to go!

Will snap a pic when its all done.

Glad to hear you worked it out, can't wait to see it up and running :-)

Hello I am in the process of building this and printed all the parts. I do not see how the y endstop mount v4 looks anything like whats in http://imgur.com/a/GQs2U and or how to use the one that I printed.


Sorry for taking so long to get back to you, it's been a busy week. If you look through all the photos you can see the progression of the mount from V-1 thru V-3 I think, I'm not sure why I never added a photo of V-4!?!? I just took a photo of it and added it to the imgur album, it should be the first one, I think that will explain how it is mounted, if not, please let me know :-)


Thanks so much, Makes much more sense now lol!

Glad I could help :-)

Great work Sonny and Quadbert! I'm very happy with this Y axis now. Top notch upgrade! Thanks so much for sharing this design! Sonny, I did like your OTHER Y axis tensioner better so I did a remix of that one to fit this upgrade. I like to adjust the belt from the front. It can be found here:


Folgertech 2020 OpenBuilds Sonnylowe Y Axis upgrade alternative tensioner
by quadrar

Thanks for the kind words, nice work on the remix!!!


In one of the pictures posted, you have what looks like a seven segment led display, in a little blue case. What is it displaying?

Thanks again, Sonny, for the idea and parts! All in all, a great upgrade. My Y carriage is nice and solid now, more importantly, pretty much silent.

For those looking to do this, I definitely suggest the updated bed support by QuadBert. I went a little nuts and printed it 100% solid PETG, pretty much making that thing last forever.

One thing to note is that I didn't have a lot of the screws laying around for this. When you buy things from openbuilds, while you're at it, grab a nice assortment of the M5 Low Profile Screws... 10,15,20mm are good to have on hand. You'll need them to mount up various things, and for a few bucks, you don't want to have to keep making multiple orders and pay shipping for not paying attention (like me).

You should have plenty of T nuts around from leftover Folgertech parts. Don't forget to put them into the V-slot before putting your carriage on, otherwise you'll find yourself taking things apart (again, not paying attention, like me).

Thanks so much for your input, and I couldn't agree more, lots of screws and lots of nut plates for sure!!! I also agree that Quadbert's mount is top notch!! Solid PETG...that is going to be bullet proof LOL

Glad you like the upgrade,

I am building this with a 12 inch bed, but I am having a difficult time finding a 12 aluminum bed mount (or solution) from the picture it seems you are using a larger bed, what are this mounts?

I am running the standard bed (200x200), however, they Y Rail should be long enough to run a 300x200 bed and bed mounts found on ebay (see links below). Not sure if the small 20x80 gantry will be large enough though, might want to consider the Openbuilds "Build Plate" also linked below...



Build Plate:

It seen that you are using the E3D cyclops 2 in 1 out extruder , can share the firmware?
My email: francishui_sg@hotmail.com

Sorry, but I no longer run the Cyclops Hot End. Although I got it to work, the firmware and hardware was a mess and it turned out to be more trouble than it was worth. I will try to track down that version of Marlin, if I can find it I'll be happy to share it with you, but I can't honestly remember the hardware setup I was running...I think there were Thermistor issues I had to work around!?!? I also had issues with slicing software, S3D was the only slicer that ever worked well for me, it's pricey but worth the cost of admission ;-) Again, in the long run none of it was worth while and I'm now running an E3D single extruder.


Hi Sonny,

Amazing work! I'm ready to to tackle this. All parts on hand. My question is that, from pictures on your website, you seem to be running a newer design of this Y-mod where the gt2 belt is mounted to the gantry on the side and the nema motor is tucked into the frame. This is optimal as my printer is against a wall How did that work out for you? and how did you attach the belt to gantry. Do you have any associated files for this variant. Totally awesome build pics comming you way if you help me out :)


Good eye, and I'm definitely running a different version on my printer. This is a great setup for an enclosure or limited space with your situation (the reason I did this version). I never posted it because I wanted to make sure the offset belt had no ill effect on prints and or the setup as a whole. I'm happy to say it has run many hours with no problems at all.

I'd be happy to share the files, but I'll have to look for them to make sure I have the latest ones, once I locate them I'll either post them here or add a completely new version!?!?


That would be amazing and save me so much time from reinventing your wheel. I will document and share on my blog if successful, giving you massive credit for these sweet upgrades!

I would create a new design if it's not too much work because the original one is still excellent and preferable to some. Yeah I'm just not sure about the effects of pulling the gantry off-center.

Sorry for the late reply, the holidays have been been a bit busy ;-)

The setup is working flawlessly, so I see no reason not to run it as I have total confidence in it.

I have not forgotten about the files, just need to find the time to locate them...I'll try to get it done over the next few days.


No problem at all. Looking forward to reading/printing your post!

I'll export the files to a STL at some point soon, but in the meantime I imported it into OnShape (see link below). That way you can get a close look at the setup and how it's assembled. If you right mouse click you can tumble the assembly. Keep in mind that there are no mates, so the parts will move independently if you click on them. If so simply reload the page and it will be back to normal. FYI: This is a view only version, if you want a working version that you can copy and save you'll need an OnShape account (it's free) and I can provide that link. If you happen to us Solidworks I can provide a "Pack & Go" ZIP file as well.



That is awesome work! I like the built-in adjustable belt tensioner along the v-slot!

I'm a Solidworks guy and now have a OnShape account if you'd be willing to pack that up for me?


Glad you caught the tension adjustment, I went through a couple versions before I stopped on that one...it works great!!

Dude, you will love OnShape, I come from a Solidworks/KeyCreator background and now OnShape is all I use (for personal projects-have to use the other two for work). It's got a bit of a learning curve, and there are still things missing, but it's still pretty robust, overall it's a great experience and you can't beat the price ;-) .

As far as the OnShape Model, it is public, so just search "Folgertech" in the public documents and this will pop up (I renamed it "Folgertech 2020 Offset Y"), once you find it you can save a "copy" which will allow you to edit it at will. If you take the time to add mates you can also add the various freedoms on movement, as you know, it's always a plus when designing this stuff.

Have fun, I look forward to seeing what you come up with,

p.s. Since you have an account you can export the parts to STL, so I'll skip that for now...

OnShape is amazing! thanks for putting me on to that! I've forked your build and started tinkering. Still learning "mate connectors". I was also wondering what is that snazzy, custom insulator you use under your build plate? do you put it between the heater PCB and the glass?

Glad you like OnShape, it's great software!!! Not sure exactly what you talking about when you say "custom insulator"!?!? Can you snap a screen shot and show it to me???


Sorry for being cryptic. I was reffering to the material with your logo that you have beneath your glass build plate. I assumed it was some sheet good to act as an insulator for your heated bed.

Haha, no worries...

That is a "Bed Skin", it's a MakerSL exclusive. They are custom made using proprietary materials and processes. Without the proper materials and tools I'm not sure they could be replicated. To even try it you would need to acquire or have access to the following: Heavy Paper & an InkJet Printer LOL

It's just a piece of heavy paper with my custom logo printed on it, it really serves no other purpose than to look cool :-) I tape it down to the heated bed with a couple small pieces of clear tape, then lay the glass over it (held on with magnets). It's been on there for several months and still look brand new. It's a fun little way to make your printer..."Yours" :-)


Hahaha! Propeitary materials! Fooled me! Thx again, looks great.

Oh man that upgrade is nice! The Y-axis is now super solid and much less noisy. I can post my build here as a remix if you don't mind.

One last question (for today). was the switch to a bowden a good move for you? I know this a hot topic but I just wanted your opinion on this. I have ate "wade" parts but I can go either bowden or direct at this point.

A remix would be fine :-) I ran a Bowden for a while but switched back to direct on this printer. It pretty easy to right a bit of additional code and swap colors in the middle of a print, hell, it's just easier to which colors period. I do run a Bowden on another printer and I like it, so it's really up to you!?!?

Hi Sonnylowe,

I am finally doing the X upgrade. While I'm at it I remembered I broke the Y belt tensioners. I think I printed them the wrong orientation.

Can you recommend a tensioner that will go on the outside of the build? Say the front? Getting under to tighten/loosen the belt is a real pain.

Still a great upgrade. I got lost in my FT5 for a while, lol. Back to building a better 2020.

Thanks for the design and the assistance.


Sorry for the late reply. I've had no problems with the Y Tensioner nor heard of anyone else having problems. When I get home today I'll take a look at the one I have to see how I oriented it for printing...I can't honestly remember!?!? However, I would think lying it on it's side would yield the strongest part...

I'm not sure what other tensioner you coudl use...there is not a lot of room under there, I assume you've done a search here!?!? If so let me know what you find and I can the model to see if it will ift.

As always, thanks for the kind words,

I worked it out. I tightened it prior to installing the bed.
I had forgotten to mention the I have a 200 x 300 bed with the 300 going along the Y so getting underneath to adust was next to impossible.
I should here mentioned that. BIG part of the puzzle.
It's good now. AND I designed a plate about 200x280 to attach to the gantry to get rid of the wobble I had going on.

Just doing some fine tuning but great build thanks for the files.

Glad to hear things are moving along...keep me posted.

Any suggestions for a bed plate for a 320mm x 220mm bed.

I've completed my build. It's awesome. Thanks for sharing.

I'm getting some shaking in fast x/y thin fill movements. I think a firmer bed plate will fix this.

That is the one I have. With heat bed and aluminum plate. It's awesome.
Can I just attach that directly to the rail plate?

I took a look at your photos (thanks for posting the "make") and I think the problem is the printed rails that hold the bed to the gantry. I ended up removing them and using the old lower plate from my FT printer, so yes, I think replacing them with either an Alm plate or possibly mounting the Bed Plate directly to the Gantry Plate is the way to go...let me know how it works out!!!


I just realized I cannot. I will lose the clearance I currently have on build that allows the bed to go over the motor. I might have buy a longer 2080.

If I may suggest...find a couples pieces of 1/4" thick Aluminum plate about the width and length of the Printed Bed Support, then use the support to transfer the screw holes into the aluminum plate. The much stiffer Alm Plate might do the trick and by using two pieces instead of one you shouldn't interfere with your current clearances...at least I hope not ;-)


I've completed my build. Mostly good except the wheels are not sitting just right and I'm getting wobbles.
Any suggestions?
I have spacer, washer, bearing-wheel-bearing, washer, then nut.

The wheel should assemble with one 1mm precision spacer (2 provided with the kit) between the bearings (inside the wheel), then it goes, Gantry Plate 6mm spacer, Second 1mm precison spacer, wheel assembly, nut.

Here's a link to the wheel assembly photo...


here's a short video show how to assemble the gantry plate with the wheels...


Hope that helps :)


Awesome. Thank you.

I missed the washer between the bearings. Goo thing I asked.

This looks great. Besides the 2020, the files here printed and the screws, what else do you need. I do not have Imgur at work so I could not see the build in full.


Everything you need is listed in the BOM at the bottom of the "Thing Details" tab, I can't think of anything else other than that right off hand. Anything not listed should come from the original FT parts.

When you have a chance you should definitely look over the photos, they will really help with assembly :)


Thanks man. I can scroll down all the way at home. Lol

I've actually already ordered all the parts from Makerparts.ca
They had everything. $115 with shipping in Canada for anyone wondering.

Hey can you tell me what the center to center size is for the lead screw and smooth rod? I am remixing the x axis to use antibacklash lead screw nuts.

17mm center to center.

Have fun and be sure to post your remix :-)


BTW: I have an anti-backlash setup for this as well:


Lead Screw Anti-Backlash - Folgertech - Prusa i3

What is the best plastic for these pieces?

I used ABS, but I think nylon would be fine as well. You might be able to get away with PLA on everything except the motor mount...I wouldn't trust PLA due to the heat from the motor...

What kind of nut do you put into the belt holder? The M3 hex nuts i used cracked the piece, not sure if you were using something else.. square nuts?

I uploaded the camera mount...


V-Slot Openbuilds 2020 Raspberry Pi Camera Mount

I only used standard hex nuts...If you talking about the belt tensioner you'll need to clean the slot out really well, the nuts are a tight fit, and of coarse that opening varies a little with different printers...


Random question - do you have a link to that sick pi camera mount??

BTW: Here's the main thingi I used for the camera mount, I just designed the 2020 mount and arms, if I can find them I'll post a remix with them in there...


Mounting system for Raspberry Pi camera

Haha, that's one of my designs that I guess fell through the cracks...actually, it might have been a remix if my memory serves me correctly!?!? Either way I'll try to find the cad model and post it.

Glad you like it :)


Where are the 6mm spacers used? Between the aluminum plate and the gantry plate? I dont think I need them if I use quadberts support (all ready printed!)

Yes, that's were I used them, as far as not needed them with quadburts support, I'm not sure, I wouldn't think so, but it would be best to ask him to make sure. Either way they seem to come in handy so I always have a few laying around ;-)

Thanks for the reply. Despite all the extra hardware I have, I never seem to have exactly what I need. Just ordered the flanged bearings - the ones I dont seem to have. This is going to be a fantastic upgrade.

Haha, it's always like that ;-) When you have a minute check the link out link below...it's new printer I'm designing for PLA only (at least for now ;-)


look at the mamba3d.
your design reminds me of my printrbot simple metal.

Yeah, it just another cantilevered printer, they are basically the same in looks and function. I'm just trying to design one based around the OB parts, and keeping it as simple as possible, with the fewest parts as possible. The current version does require some laser cut parts, although all of them could be 3D Printed. Once I'm done with this, and happy with the results I'll do two more versions, one with all metal OB parts and one with all 3D Printed parts.

The IndieLC (see below) is another cool Canti Printer, it very well engineered...I took a lot of inspiration from it.


I would have simple built one of those, but I wanted to do my own thing...hopefully it all works out in the end ;-)

The Printrbot Simple as a pretty cool little machine...I'm a fan!!! I checked out the Mamba3d...it's pretty cool as well.

Just curious because I dont think it really matters....Why did you move the stepper motor from the left to the right side?

No particular reason, it's just how it played out...

I only want to know what size wheel did you use on this set up?? I see they carry a mini size and guessing the other one is their normal size. Thanks for this dedication to a new design!

Glad you like the design :)

It's the Solid V-Wheel Kit...


Cool! Placing my order right nopw and already printing the parts.

I think I'm gonna order from them again soon to build a cnc router. Never new about this place!

Thanks again for sharing your design!

Can anyone who has completed this upgrade tell me what size screws did you use to go into the end of the extrusion? I finally got around to printing the pieces.

I used standard M5 x 8mm SHCS, I tapped the holes prior to installing the screws though, OB recommends their self-tapping screws. However, I bet you could find something suitable at the big box stores or your local hardware store!?!?

Thanks! I will buy a tap when I get the screws.

Anytime, and thanks for bring little things like this up, I have all these tools lying around and I often design around what I have available to me...I forget that not everyone has these tools!?!?

Just a couple questions....

What are the technical advantages to using a v-slot rail system for the actual movement of the y-bed (vs. using precision rods with a quality LM8UU bearing)?

A precision-ground stainless steel rod with a quality linear bearing would be hard to up[grade from when it comes to precision... what bearings are used on this platform for the actual y-bed movement?

Even a good lm8uu with hardened steel precision chrome rods, which have tighter tolerances than stainless introduce a lot of slop. Whether it matters on an fdm printer is questionable. You do however get a lot of sag in an lm8uu setup at anything longer than 400mm, so if you must stick with linear bearing guides I'd go with lm10uu. This setup is very smooth on my cnc using makerslide, which is very similar, even with all the carbon fiber and aluminum dust flying around. The increased diameter of the wheel surface over the guide is likely why. Think of 40 .5mm balls rolling over an imperfect surface compared to a 22mm wheel with sealed bearings. The technical advantage is a much stiffer y-axis/build surface. Hope this helps.

Sorry, but I'm not an engineer so I'm not sure from a purely technical standpoint what the advantages are over rods and linear bearings.

My design goals were to come up with a quieter, smoother and inexpensive alternative to the cheap setup common in these printers. Setup difficultly (or lack of) also played a big part in the design, I went with thew 20x80 rail over two independent 20x20 rails for ease of setup.

I can tell you the ball bearings in the V-Slot setup move far more smoothly and far quieter than the stock setup, even much better than the Igus Drylin linear bearing which were a big improvement of over the stock bearings. And when I added the same V-Slot system to my X-Axis I saw a pretty significant quality increase as well.

I agree, you could certainly spend far more money adding precision rods, bearings, and pillow block, but that would greatly increase the overall cost of the upgrade, and I believe it would exponentially increase cost well over increasing in print quality. You could even go with a CNC quality linear drive system if you wanted...but again, I think that's over kill on these printers!?!?

This a $60.00 upgrade, with a much higher return :)

Regarding the bearings, the OB Wheel bearings are the least precision at ABEC 1, yet the increase in the smoothness of the drive system still out preforms the stock setup ten fold...IMHO

Have you already fabricated the X carriage upgrade? My printer is kind of jerky on both X and Y movements, and I think it is just the LM8UU bearings having more friction on the stainless bars than they should, and are causing the bars to vibrate; they feel kind of grainy when you move them by hand, too. I have tried putting some thin oil on the bars, but haven't gotten much better results (or any really).

I am thinking this might solve my issue, but I am curious if it works on the X axis as well.

Haha, noise was the main reason I designed this upgrade, I wanted a quiet printer. Now the loudest thing I hear when printing is the hotend fan :)

Yes, Gen-1 is done and running on several printers. I just finalize Gen-1 this morning and may have it posted today, at the latest this weekend.

There is also a Gen-2 in the works that I am currently testing on my printer, it is more compact and would allow an enclosure. Both the Y and X upgrades are getting great reviews from those how have installed them.

If you haven't been there already, here are a couple sites worth looking at...

RepRap Folgertech Thread
Folgertech Wikia Page (under development, but already has my upgrades detailed)

Great! And thanks for the links! Is your Gen 1 version of the X upgrade the one pictured in the snapshot of your CAD data? I am excited to get these upgrades installed. Thanks for doing all the work!

It's comments like yours that makes all the work worth while...you are very welcome!!!

Yes, I think that's what you're most likely seeing. Here is a album with photos I took while it was first tested, there are some small changes but it's basically the same...


Please keep in mind, those were test parts some have been modified and I didn't take a lot of time making them look nice when i printed them...I did on my Gen-2 parts though ;-)

The X-Axis Gen-1 upgrade has been posted, you can find it here:


Folgertech Prusa i3 2020 X-Axis Upgrade (Openbuilds V-Slot Rail System)

Awesome! Thanks again! I will start printing these this weekend. If you don't mind, I have a couple additional questions:

I know I can do whatever length I want, but out of curiosity, how long are the rails shown on your Y upgrade? -Nevermind, found it, 500mm, sorry!

And also, your Z axis threaded rod looks different than what was shipped with my Folger Tech printer. Have you also upgraded them, or am I just imagining things?

I think you can cut that rail as short 420mm...but I'm not sure as I've left mine 500mm.

They were upgrade to 8 x 2mm pitch Lead Screws with 4 starts, they can be had from several different places, however I got mine here:


You can also get them here, if so buy a couple extra nuts while you're at it...



To be honest I'm not a big fan of the 2mm pitch with 4 starts, I think the one from Folgertech are 1 or 2 starts!?!? If so I'd suggest those over the 4 starts leads as they seem to reduce the resolution to much IMHO

I have actually designed Lead Screw nuts I'm machining out of Delrin that will use M8x1.25 all thread that I am currently polishing. I think it will be much better when using Auto Leveling and Z retract...

Hmm, good info. Sounds like I will just stick with what they shipped for now then. Looks like I might have to modify your design slightly to incorporate standard nuts? Or buy a few of your Delrin ones! (can't seem to find any flanged lead screw nuts like it looks you have designed this for with 1.25 pitch)

Also, OpenBuild is sold out of all the gantry bundles (mini and full size). Bummer! But I will order some when they become available again. I am excited to quiet down this printer a bit. I love it, but it is so dang loud and jerky on those linear bearings!

Thanks for being so responsive to my questions! I am very new to the 3D printing world, I appreciate it! I am still learning a lot, baby steps...

I was you a few months ago so I completely understand :)

As far as the gantries, check to see if they have all the hardware available, sometimes they just run out of the kits!?!? If you look at the mini gantry page it will list all the components at the bottom, I actually had to buy everything separate for the 2080 gantry. The only advantage to the kits is you save a couple bucks, not sure that matters enough to wait LOL

Thanks for bringing up the Lead Screws and the fact they are an upgrade as well...I'v had the lead screws so long it never crossed my mind that others my not have them. However the fix is easy, I just designed an adapter so you can use the stock M5 nuts and all thread, it will mount like the brass lead screw nut, just allow you to push in the M5 nut in from the bottom, but make sure you do that before you install the adapter...

Hi sonnylowe! I really like the upgrade and I think I will do it to my printer. I have a quick question: Are these nuts ( http://www.banggood.com/8mm-T-Type-Lead-Screw-Nut-Brass-Nut-For-CNC-Parts-p-989198.html ) compatible with these lead screws? ( http://openbuildspartstore.com/8mm-metric-acme-lead-screw/ ) Thanks!


I am 99% sure they are, I ordered the same ones and they worked fine with my M8 2mm pitch 4 start LS...I did not buy them from Openbuilds though, they were from Ebay:


I might order since it will only be $5. Have you posted the design that allows you to mount these nuts on the x carriage as you mentioned a few comments up?

They are what the X-Mounts were designed for, so they will fit. Please keep in mind, you will need to tap the M3 mounting holes in the X-Mounts to get the screws to go in...

Where are the X mounts that were designed for them? Sorry, I'm a little confused right now.

This is the Y-Axis upgrade, it does not require the lead screw nuts, the X-Axis upgrade does...it's located here:


Folgertech Prusa i3 2020 X-Axis Upgrade (Openbuilds V-Slot Rail System)

Oh OK. Thanks for your help!

You're welcome :)