CMM overtravels in X axis...

[Jeff Hunt]

I just noticed this today...If I have my machine speed set to 100%, as the CMM moves to a point in the X axis, it will pass it up & have to go back a bit because of the speed that the arm is moving at. Sometimes this gives me an X axis lag error. What do I need to look at to find the problem?

[Wes Cisco]

I don't have an answer for you, but if you tell us what type of CMM & controller it might help someone be able to help you.

[bw_bob]

If it was me i would just slow my machine down. I never go @ 100%

[Jeff Hunt]

Its a Brown & Sharpe Validator Horizontal arm with a desk style "world class" controller. It just started doing this...

[JamesMannes]

We have a couple of older bridge type BNS's. I have seen this problem with one of our older machines, and what it is is the plastic gear that drives the x axis. It has either sustained a crash, or the gear is getting old(on our machine it was a crash). We tightened it up(it had come loose after the crash). And for now we are good to go. Luckily we get calibrated in June so the Tech will probably be asked to replace the plastic thingymajobby.

[Matthew D. Hoedeman]

It might be getting dirty (drives and belts) or they might be getting loose. The drive system is also the break, if it is loose, it will go too far and have to back up, but it you get it too tight, it will bind.

[craiger_ny]

Lag error means the machine has not reached it's destination in an alloted amount of time. The controller figures it should take x amount of time to reach its destination and if it does not it errors out with a lag error. It is for when there are no obstructions per say but does not get there when it should. Go with the advise of the guys that susspect the drive system, and naturally start with the cheapest solution. Is something rubbing, dirty etc anything that will physically slow it down but not neccesarrily stop it.

Craig

[Jeff Hunt]

It was a combination of bearing wear & wear on the drive roller. We upped the tension & everything is running again. Thanks for the suggestions.