What is acceptable radial movement of carving bit tip?

[m4pc]

I purchased a “used only once” CompuCarve on eBay and received it yesterday. After a quick once-over looking for loose and missing pieces, I cut a couple of sample carvings. I wasn’t overly impressed with the detail on the prices that I cut. As I examined the machine for possible causes, I saw visible radial movement in the chuck. At the tip of the carving bit it was even more amplified. I originally guessed the bit adapter was loose in the chuck or chuck was loose on the spindle, but I can see the spindle moves with the chuck and have checked that it’s tight. The bit adapters fit in the chuck with no discernable play.

I measured the free play using my dial indicator while keeping the y- and z-trucks motionless: At the chuck, side-to-side and front-to-back motion is 0.045 inches. When the movement’s measured at the tip of the bit, it’s 0.075 inches.

This motion seems excessive to me. Is there a spindle bearing in the z-truck that can be tightened? After looking at the amount of motion, I wonder if there’s even a bearing there at all.

Any recommendations or suggestions?

[Malfunction]

do you get any "wiggle" in your bit after it's cocked (while sitting idle)?

put your finger on the end of the bit. there should be absolutely no play. if there is play, try recocking it a few time.

is the play in the bit or the truck? if it's in the truck, then the truck may be loose.

if there is no play while idle, and there is play while it's running, you should call CW and ask them what they recommend.

[m4pc]

With both of my adapters, the bit locks into the chuck solidly with no relative motion between the chuck and bit.

When I put my finger on the end of the bit (with the machine stopped & unplugged!), that's where I see the wiggle - measured to be 0.075 inches. It's not just the bit moving, either - it's the whole spindle (I can see the threads above the chuck moving relative to the z-truck).

While carving, it looks like the bit moves side-to-side.

Already verified the trucks are pretty tight.

Any idea if CW will be open on President's Day holiday (19 Feb)?

[The Bard]

Yes, they will.