After several iterations, I have a Y axis design that works quite well. I ended up using smooth rods 40 mm longer than normal and clamping them to the underside of the extruded aluminum. [
www.flickr.com]
I used steel clamps, but plastic could be used as well. I moved the rods as far apart as I could. Next, I mounted bushings to a Di-Bond Y plate as Nophead describes in his blog [
hydraraptor.blogspot.com]. I used these bushing holders: [
www.thingiverse.com]
Using 180 degree bushings on one rod means the alignment of the rods is not critical. Just square the rod with the self aligning bushings to the frame and center the other rod in the 180 degree bushings like this: [
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Finally, I mounted the aluminum bed with silicon heater to the Di-Bond using long bolts with nylock nuts for leveling.
I've been using it for a couple of weeks now and it seems to be solid, even at high speeds.
I really like the self aligning bushings for their low cost, quiet operation, and low maintenance. They work best when used on only one shaft per axis though.
