[cgallery]

I've run into this problem before. I'm pretty sure it boils down to things I'm doing incorrectly, or have something configured incorrectly somewhere.

I recently cut two little baffles for small full-range speaker enclosures. These use a Faital 3FE22 driver (if anyone is interested).

The way I do this is, I setup a 12x12 piece of MDF in clamps. I get the X/Y/Z setup, and I cut a part. Then I jog the machine over (moving the X), set X to 0 on Mach3, and then start the program (to cut a second part).

But here is where things get strange. The hole on the 2nd part is shifted. Looks like it was spot-on the first baffle, but it dropped (in the Y) about .13".

My machine is using a recent (2-3 months old) version of Mach (licenses), along with a UC-100 motion controller. I draw the part in AutoSketch and then use LazyCam.

Any ideas?

I'd say my machine lost steps somewhere but the outside is cut after the hole, so I'd think that would be offset by the same amount.

I'm just going to add that one other problem I've experienced is parts that aren't square. Maybe 1/32" or 1/64" in 6". I'm trying to wrap my head around that, I had figured it had to be something in the setup of the software but I suppose one axis could be out of square to the other on the machine, too?

[ger21]

It's very hard to see any difference in the pics, probably due to the angle?

Is the hole lower in the bad part? Not sure which is X or Y here.

From the pic, it looks like both of the cuts are the same, but all the cuts appear to be shifted down, not just the hole.

Out of square parts would generally mean that your machine is out of square.

[cgallery]

Yeah the hole is actually shifted down on the second part, by .13". Almost maybe half the D of the bit (.25")?

Tonight I'm going to try to figure out how to square the machine up. Maybe I can find some movement at one of the ends of the X or Y.

So much I don't know...

[ger21]

Check for mechanical issues, like loose setscrews or couplings. That can cause issues that seem like lost steps.