[CarveOne]

grahamshere,

This premium grade oak 1x4 lumber is expensive, very dry, and I bought it for the additional rigidity and good looks, and have not had it warp on other home projects I've used it on before. Where I normally have to buy pine lumber the stuff is not at all stable and I wouldn't use it for building one of these machines. Making the frame and gantry out of steel might have been less expensive.

I don't think the 1/2" leadscrew concern is valid unless it happens with rough poor grade allthread rods and/or threaded couplers that are cut too close to the minimum diameter. I could believe that properly sized 1/2" althread and couplers could have a little more frictional drag than the 1/4" or 5/16" allthread and couplers due to the larger mating surface area. This is one reason I ordered the 425oz/in steppers. They will have the additional torque at lower speeds and still have enough torque at the higher speeds (I hope). I tried running an allthread rod through a 1/2-13 threading die to smooth out the rod, and running a 1/2-13 tap through a coupler to eliminate the tight spots, eliminate binding, and it reduced the drag to a very tolerable level. With the anti-backlash nuts this rod will work fine except that the rod has a small serpintine spiral in it that I can't tweak out of it by hand.

rc_flyer is using his machine again now that he has completed his upgrade effort (is it ever really completed?). He seems pretty happy with his new 1/2" rods so far. I don't recall him complaining about x axis rod whipping either.

Gotta get back to making some more parts. Later guys.

CarveOne