Problems with Sherline CNC Mill

[44-henry]

Hello, I'm having problems with a Sherline CNC mill that our department purchased a couple years ago and which has pretty much sat unused during that time. I started playing with it this afternoon and found out that Z axis is not responding to keyboard commands. Both the X and Y motors are working fine, but when I try jogging the z axis it makes a grinding/humming sound. The wheel jerks, but will not turn fully. If I switch connections with one of the other axis it works fine however. I've tried the Z axis connection on both the X and Y axis with the same result (it won't work). I'm guessing there is a problem with the card, but I'm hoping it is something simpler. Since nobody played with this thing since purchasing it (annoying I know) I'm guessing the problem might have existed all along. There is the other 4th axis port, how hard would it be to configure this port to run the z axis? Any information would be greatly appreciated.

Regards,

Alex Johnson

[Fixittt]

clean and lube the machine. manually run the axis up and down by turning the motor. My guess is that stuff is sticking. The gibs are a probably dried and stuck to the column. Or maybe WAY TO TIGHT!

[Dr Pete]

After you make sure everything can be moved manually with the stepper motors off you can easily reconfigure the 4th axis to run the z.
My guess is you have a bad z chip, this happened to us, easy to replace. I think they were about $80.00 back a few years ago.
If your handy with a screwdriver you can replace it easy.
Good luck

[44-henry]

Thanks for the replies. Everything is free moving and well oiled. The Z axis moves fine when I plug one of the other connections into it. I talked to Sherline today and they thought it was likely a chip problem also. I guess it is either try and repair it myself or send the whole controller back to them. Thanks again.

Alex