Hello all,
Please bare with me, If I have left out any details please let me know.
I recently purchased a Bridgeport Interact 1 MK2,1988, s/n 660600788C with Heidenhain 151b control. The mechanics of the machine are superb, however the mill had a 'crispy' KTK spindle motor driver. I was rather pleased with myself as I have managed to repair the spindle driver myself.
After the driver had been repaired and refitted I thought 'great plug it in and watch it go' Hmm, life's never that simple.
To cut a long story short, the x axis drive motor (SEM Motor - type MT30R4-58 - Serial Number F04420) had a shot armature (Gone to ground and was blowing the drives supply fuse (MF 1 in the control cabinet) as soon as the 'drive arm' button was pressed) so I had our motor rebuilders fit an armature from another SEM motor that we had on the shelf that had a broken end cap (Same type numbers). The motor now is basically fine (i.e it spins up on a DC supply) and generates a good Tach voltage.
I should point out at this stage that all three axis drives are good as are the Y & Z motors and the X, Y & Z machine wiring. These have all been carefully checked by substitution.
The problem we now have is the "new" motor is still blowing MF1 fuse and making a terrible noise, arcing and juddering as soon as the 'drive arm' button is pressed.
My main question is this..... When the motor rebuilders stripped the motor the encoder would have been removed (and the disc taken off the shaft). If the disc had not been positioned back exactly as it should have been would there be any chance that the control is trying to 'park' the motor in an impossible position? Or can any one please shed any light on these symptoms?
Generally I like to try and sort these problems out myself (more of an interest thing than a cost saving one) but I must admit after a scary number of hours and a diminishing number of ideas It would be much appreciated if someone could spare a minute to answer with any ideas?
All the best, and thanks for your time.....
James