Z axis motor brackets

[bdring]

I think I have a bunch of brackets left over from the original batch that I did. On the PS:One unit I am working on, I laminated two together with epoxy and it is quite stiff. I can add these to the store when I get home tonight. I'll try to set it up with coupon code or something so existing builders can get them (4 max) for the just the cost of shipping. I don't need them.

[roberlin]

BTW, you've got acme lead screws? Mine has 8mm threaded rods. Do the kits now come with that or did you upgrade?

I didn't buy the kit, I just cut out all the custom plates/feet/etc. with my Shapeoko. As far as I know the kit still comes with 8mm.
The ACME is 3/8" 12 tpi "precision grade" from McMaster-Carr (I have no idea if it's straight or not -- Bart said the stuff he got there was warped). With couplers from dumpster-cnc and a nut-block made by the member Improbable Construct on the Shapeoko forum (since they are sized for a Shapeoko they require some adjustment to the design of the ord-bot plate it bolts onto, and a spacer).

...I've had a hard time checking square of the threaded rods though. Just took calipers and found the same 3mm difference at bottom and top on both sides...

Yeah, I don't have a good idea on how to get these totally square either. You can get one axis by using calipers to check the distance from rod to v-rail at two points (which it sounds like you're doing). But the other axis seems a little trickier (I just tried to make sure my motor mounts were straight for that). I think I remember that Orcinus had good luck by using the "gravity method" but it didn't work for me.