Wallace Y Rack & Pinion Drive
by Komb, published
I didn't like the belt layout under the bed, and after building finding the once tight belt was now slack, I did something about it.
I borrowed parts from theodleif's Prusa R&P design. The Y motor mount from Domonoky's casted Wallace and the standard 6mm bed mounts for the Wallace.
You can see it working here: http://www.youtube.com/watch?v=LibplYh-9XI
y_motor_holder_rack.scad is a scalable motor mount for those looking for the smaller wallace version. I would like to atribute the kind person who sent it to me, but can't seem to find the e-mails...
- Print parts. You might want to change the fill direction for the Rack or full plate to 0.
1.5 Buy 6mm threded rod 28cm, 280mm long. (For my bed anyway...)
Re-mount Y motor using Y motor mount. Use only 2 screws. The Rack travels over the other holes. Leave loose on rods.
Assemble Rack and bed mounts.
Impotrant: Be sure the Pinion and Rack are facing the same way.
Pinion colar should be at top of shaft. Use either press-on or screw mount pinion.
Pinion should be flush with top of motor rod.
Mount Rack to bed with holes for belt screws.
Test fit to ensure Rack and Pinion line-up verticly.
Slide belt ideler with plastic pullies removed, Just the berrings on the screws, to sit behind smooth side of Rack. They don't actually touch, unless someone makes rings for them, but are close enough the Rack has nowhere to go.
Snug Y motor up to Rack. Be sure Pinion and Rack are fully engaged. Do Not put pressure on Rack. Slide Ideler block till it meets Y motor. Tighten into place.
Manualy slide bed and watch R&P to verify working condition.
- Motion Tests. Adjust Y steps in Firmware. (Mine is at 77.4790)
You will never have to adjust the belts under the bed. :)