Hi,
Im new here, and Im going to take a stab in the dark and see if anyone is familiar with this type of a problem
We have a Bridgeport type mill with a dynapath 40 controller. The problem is, that everyonce in a while the X axis looses its location/jumps and needs to be re homed. its an x/y table motor controlled. All the computer hardware has been checked out with no problems. We havent looked under the table. The problem happens once in awhile with no way to repeat it. The axis will be moving or rapiding to a point and the operator will discover that the position is off .1 .01 .05, etc with no servo, or computer alarms.

If anyone has ever had this type of a problem please give your input. Ive had several machine repairmen in to see it, and no one can solve the problem.

thank you

You may want to check your BIOS if your controller is PC based (not familiar with Dynapath but had the same problem with our PC based motherboard on our CNC mill).

The CNC software was written BEFORE the LBA (large block access) concept was developed. Turns out that the PC was writing stuff to the hard drive in an area it couldn't find after it did it. Turned OFF the LBA option and this helped.

We also found that the "write cache to disk" option was OFF in BIOS. Thus, when you shut off the 'puter, or did a new operation, the computer didn't write the origin resets to the approprialte file before moving on. Reset the option to ON and the think hasn't gotten lost since.

If it is stepper driven, look for binding as this could cause step loss. If it is a servo, check the encoders to see that it is sending back pulses properly. Lost feedback pulses will result in mispositioning.

May want to defrag the hard drive. If is is fragged badly (if it is a DOS system), you can lose data as the data is scattered all over the disk. Clean out old tool path programs.

May want to reload the O/S and CNC code - could have gotten corrupted.

That should get you started in troubleshooting.