[jaztau]

I hope someone can help me, when the x axis starts moving it is making jerking movement and the result is a very bad finish, when it reahces the specified point it is as if it jumps over and back around the point the whole time till it eventualy stops on the point or a position error is given, the probleme started a few months ago with the jerking movements only sometimes and it got worse with time, any selutions please.

[machintek]

What kind of machine? What control? We need to know what is inside of it!

George

[jaztau]

I t is a Bridgeport Series 1 interact tnc 145

[machintek]

So in a feed rate it jumps. And because we have more data we know that it has servo motors with Bosch drives and that all this is almost 30 years old.
First, I would swap the x and Y motors. If the problem follows the motor it may need rebuilding.

George

[jaztau]

Where could i find any info on stripping the motors and can it not be the encoders because when the machine starts up and moves over the reference points it moves very smoothly...only after its ready for operation does the jerking start...in program mode and by moving it wit the handwheel.

[jaztau]

Hi everyone..sorry for only replying now...the problem was actualy the brushes in the servo motors..they where to short ( they were worn out) the x axis works like a dream.

[gridley51]

I see you have found the fault.It pays to check brush length and to blow the carbon out of these motors every so often.SEM have a pdf on their website re maintenance of there motors.
Mark.

[jaztau]

I have the same problem but blowing the carbon out and replacing the brushes didnt help so i changed the Servo motor and now i have a different problem, I cant get the machine to move over the reference point, it keeps on saying wrong reference point...what am i doing wrong?