[KSky]

I know it sounds crazy, but my Series III mill will only go forward, no matter which way the switch is set for manual or programmed.

I've had my Series III since it came out and it has 1000's of hours on it so I am not new at this and I assume some setting in the VFD got switched somehow. I was right in the middle of a long series of holes and suddenly broke a 3/8 drill. Very odd I thought so I put a new one in and started over and I watched it and it was spinning in reverse. I shut off the mill, let it sit, and tried again. The spindle works great, just no matter how it's set, it only spins in reverse. The speed control works just fine.

I'll call Tormach in the morning, but any idea what VFD setting and how it suddenly changed.

[RTP_Burnsville]

I had a similar issue with a Series I..... The spindle would only turn in reverse at a fairly low RPM. It turned out to be a bad control board in the mill.... In my case it happened after a near by lighting strike.

Robert

[KSky]

Once again I was super impressed by Tormach tech support. Got a message this morning before I woke up. Support told me that most likely it was the forward/reverse relay and gave me instructions on how to bypass it for now. (I am right in the middle of helping a high schooler with their senior project that is due Tuesday). I can get a new control board for $550 or so which seems reasonable or I can replace the relay myself, which is what I might try first. My machine is almost 10 years only and has been in constant use so these things are to be expected.

So all good thanks to support.

[Contract_Pilot]

Relay is easy to replace I believe it is Relay K4 part # srudh-sh-112d1 and only a couple bucks, just use a good desoldering iron and soldering iron and good flux made for electronics.

Schematic https://media.githubusercontent.com/...31045%20R6.pdf

I was planning to add relay bases (Sockets) like I do with the lathe PCB's but there is not enough room on the board between the relay bases.
https://youtu.be/kC285l18klE