Ah ok, so its output 2
Try this go to Ports and Pins, Spindle Setup, enable the spindle relays, change M4 output to 6 then disable them again and apply.


Hood

Son of a....  Yep that's it.

Cheers, mate!!!

 

M3 was already using 6, so now it's m3=5, m4=6; does that seem OK?

Next time you're in Boston, the first round's on me.

dh

That will be ok as long as you are not using outputs 5 or 6 for anything. M3 wasnt using 6 if I recall, the relays were set as 6 for M3 but they were disabled, think you have a step/dir spindle so no relays.
Hood

Icing on the cake: 

Psyched to have everything sorted, I started putting misc. BOB's back together and getting cables re-routed back to their proper locations.  Unplugged the G540 and relay board, but somehow left the DC spindle motor plugged in.  Pulling the cord around, touched a bare end to the computer chassis... "pop!" "flash!"  Fried the Sherline Speed control board.  Laughing to keep from crying.  Will order another board tomorrow.

But cheers, anyway, Hood.  I really think the finish line is in sight (despite myself!).

Sorry to hear that but these things happen I suppose, if it hadnt happened now it likely would have at some point in the future.
Hood

Ok, I've replaced the Sherline Speed Control Board, but I'm getting no motion.  I REALLY hope I haven't fried the VFD output on the g540.  I know it's opticoupled, so does that mean it's safe?

In Mach, when I start the spindle, the Dwell light flashes once, but then stops and the spindle RPM has no readout.  I don't think I've changed any settings re: ports/pins....

  ?

LOL - I put the rocker switch in 180 degrees, so "On" was <<OFF>>  sheesh......

Up & running.  Still have a weird fluctuation in the spindle speed/sound, though....