Big problem here

[Shacky]

I only have time to carve in the winter months and am getting a late start. I sent in my machine last summer for LHR to do a major service. Repair and replace anything they see that seems like a good idea as well as all available upgrades.

When I got it back, I did one small project as a test and everything seemed fine. Now, I am ready to make some signs and have a big problem.

Everything starts up OK and it starts carving the sign and then I can hear it start to struggle to spin and then it slows down and stops spinning. This happens after a couple minutes. The machine continues to go back and forth as if it is carving, but whatever bit is in is stationary. When I open the lid, I try to spin it by hand to see if anything is catching or binding and it seems to spin freely.

Any tips on how to proceed would be greatly appreciated.

[fwharris]

First thing I would check would be the motor brushes.

[Shacky]

Would that have been these brushes or are these for the xyz motor? (I got all this done, plus the upgrade package.)

[Shacky]

I'll examine the board, especially the capacitor. I'm not too optimistic on it working itself out as it only did one small project well and has bogged down on the next two. I may not get to examine the board until tonight or tomorrow, but I'll post back. Very grateful for your assistance, gentlemen.

[bergerud]

I would pull the motor and split it apart. (Note the hidden screw in the small blower pipe.) You might get lucky and see evidence of a part or connection getting hot. Just take off one half and make sure you can put it all back the way it was.

[bergerud]

Surely the motor brushes cannot be worn out if LHR just checked out the machine. A brush could, I suppose, be stuck. My bet would be a poor connector. Have you run the cut motor test?

[Shacky]

Doesn't the Cut Motor Test, just switch the motor on? It works during board setup and it works at the very beginning of the project. Then it just bogs down and quits.

[fwharris]

It does show they installed new brushes. Yes the cut motor test just turns on the motor. Worth doing to see if it bogs down with out and load (no cutting) on it.

[bergerud]

Doesn't the Cut Motor Test, just switch the motor on? ... Then it just bogs down and quits.

Yes. Run it and see if it bogs down and quits. It is an easier and safer way to trouble shoot than running a project. Maybe you can hit it and it will start running again!

[Shacky]

The solder connections look ok to me. I checked the resistance across them. Not sure what I'm looking for. You can see I set the ohm meter at 20k.
BTW, before I even touched the board, I inspected and made sure that the wire connections were all good and tight. Also, no corrosion inside either side of the connectors.