··=[ SDX's AntiZ ]=··
The Anti-Z-Wobble Guide for Acrylic Geeetech Prusa I3 pro B
Just another anti wobble guide... but this one is made by me ;-)
How to assemble...
What parts do I need?
- 2x AntiZ Guide
- 2x AntiZ Spacer A
- 2x AntiZ Spacer B
- Double sided adhesive tape
- Allen keys to unscrew the brass nut and loosen the coupler
- Shoe laces or anyone who's holding the X-axis for you ;-)
What are the limitations of this mod?
Because of the hole size in the metal part, this mod can only compensate wobbling of +/- 1mm. Depending on the friction between the two spacers, there could be some force transmission left and may cause a minor pattern. The less the friction the better the result. If you find anything better than the seperating film of the adhesive tape as friction bearing, please let me know.
So... what now?
- Do any nice print for before/after comparison :-) Use any better setting, so nobody will flame you because of the poor quality (see comments for this Thing) ;-P
- Print all the parts to print. You should do some test prints. The fork from the guide should be able to slide smooth on the 8mm rods, but should not have a lot of play! Because of your wobble, your parts will be printed a little bit larger. I used "horizontal size compensation" in S3D to get the right size. I know there are similar settings in Cura (Horizontal Expansion) and Slic3r (XY compensation). If your guide fits, you can print the spacer with the same settings.
- Now take your double sided adhesive tape and cut out at least 4 (2 for everey side) rings in shape and dimension of the Spacer B wider side. You only need the seperating film. It's easier to cut without the adhesive film. The separating film is your friction bearing :-) Two layers of it are extremly slippy! Try it yourself.
- Unscrew all 8 screws that keep the brass nuts in place.
- Now you can move up your complete X-axis. Do it and fix it with the shoe lace on your top frame... or ask anyone to hold it up while you're doing the rest.
- Now loosen the screws on your couplers that are clamping the threaded rods. If your couplers are screwed on to hight on the stepper, loosen that screws too and fix the coupler as low as possible. There won't be much space after installing the guide (see Picture 1).
- Remove the brass nuts just by unscrewing them.
- Fix the brass nut upside down (longer part upwards) in the guide. If you haven't used the M3 washers to fix the nuts before, you should do it now. The M3 screws must not stick out of the upper side of the brass nuts!
- Now assemble everything. From bottom to top: Guid, Spacer A, 2x "friction bearings", Spacer B. The flat side of the spacers should face to the Y-axis linear bearings block.
- Fix your threaded rods in the couplers.
- It's time to align your X-axis to your Z-axis. Just rotate one of your Z-axis threaded rods until the distance between the Z-axis motor holders and the lower X-axis rod are equal on the left and on the right. You should hold the other threaded rod while turning, because of the power that your stepper motor generates (yep... it's like a dynamo) may move the other motor!
- Carefully adjust your Z-endstop and the buildplate hight. I removed the glass before doing this... saftey first ;-D
- Now level your bed and print the gcode from point 1!
Is there anything to improve?
OF COURSE! And here's where you could be the maker :-) Try, do, modify, fail, succeed... if you find anything that could improve the print quality, let us know.
My next steps will be:
- Get rid of the chinese couplers and replace them with ridgid and perfect alligning ones.
- Rebuild the Z-Axis with a much more rigid linear guide.
- Replace the threaded rods with acme threaded ones (from a industrial supplier NO chinese stuff)
Picture 1: Coupler placement and remaining space
No Marvins were harmed during the testing of this Prusa ;-)