Mach 3 Backlash problem

[gauthib12]

Hoping for some help to get back up and running. I was running ok but decided to upgrade to a faster CPU I am running windows XP  mach 3 version (Mach3 R3.043.022 ) the motors were tuned before to 154 velocity and 20 acceleration... without the backlash on I get no weird sounds but with it on I get this:

http://s123.photobucket.com/albums/o307/gauthib12/?action=view&current=DSCN0700.mp4

and my parts are not measuring as per the drawings for example a .304 hole turns out to be .293...

Really hope someone can help, not sure what ether relative info needed but shoot away, I am also still relatively a newbie

Thanks,

[RICH]

Your link didn't work on my end.

If your steps per unit are correct and the backlash is set correctly you should be able to machine fairly accurately, if not, then one of those parameters are not correct.
Note that the backlash and steps per unit can be different depending on the quality of your screws.

RICH

[gauthib12]

Hi Rich,

Thanks, I am pretty sure that the steps are fine because the machine was working fine before I changed computers, I checked the Y axis and it is not binding, I can turn it all the way to the front and all the way back by hand and it is not sticking nor is X.  With the backlash on I am getting a squealing sort of sound with it off I don't, I'll need to recheck the amount backlash.. I tried to cut a circular ring with .2855 ID and .400 OD and it's not perfectly circular the ID is 0.273 and OD 0.418 it looks sort of slanted on the perimeter...? I did recently tram the machine but it was within a couple thou all around so I don't think it's the tram, I've increased the shuttle acc to .05 seems to help with the squealing and a tuned down the steppers but the main thing is that it's not cutting anything to within acceptable tolerance?