Here’s a new Y motor holder that’s been posted to Thingiverse recently. It moves the motor in within a couple of millimeters of the belt path, virtually eliminating motor torsion, and is so beefy that any remaining torsion is negligible. It’s also snap-on so you can put it on and off without removing the rest of the stuff from the bars, and it eliminates one of the fender washers, two flat washers and a nut. I like it.
As with a lot of really great Mendel improvements, this one was designed and posted by Triffid Hunter.
It goes on to the smooth rod in two parts and clamps on. It’s a very easy end to assemble, and is also incredibly sturdy. It only uses a single nut because the nut gets clamped between the layers. It uses bolt-on PLA bushings or it could be fitted with other types of bushings. It uses far less plastic to print, is a lot less fussy and prints in about 1/3 the time that the standard X end does.
The X ends have been, for me at least, the biggest pain in the butt of building a printer. This makes it a lot easier.
Downside: it puts the motor back into the traditional position rather than the Iteration 2 position. I actually prefer the motor in this position, but it does require more timing belt to work. My 950mm belt wasn’t long enough to do this AND get around the belt tightener that I like to use, so I had to tension the belt with a pair of long nose pliers. Also the spacing is a bit different which caused my belt to rub on the idler’s fender washer hard enough to stall the X carriage, so I had to insert a bit of paper under the idler to shim it out, and now it runs perfectly.
On the upside, this design allows for the use of any pulley you want – the current Prusa motor end only fits a 36 tooth GT2 pulley if you carve some of the plastic away first.
After using the Pink Panther woman print to determine that yes, I have significant Z axis wobble, I found the beefiest solution I could find. This is it. It’s a lower bearing holder integrated with a lower Z smooth rod holder. Like a heck of a lot of excellent Prusa improvements, this one is designed by Triffid Hunter. Thing 12785 on Thingiverse.
This not only holds the bottom of the rod still, but it takes the downward thrust off the motor. It’s beefy as heck too. I’ll print one for the other side now that I’m happy with it and then try the Pink Panther again, maybe in PLA this time. I saw that someone printed a Pink Panther at 0.01mm layer height. Yeah, 100 layers per millimeter. crazy.