Macturn Disk brake calipers dragging / stuck on

[mkd]

Machining 4 axis slots was going fine until the dreaded SVP alarm.
Undeterred, I restarted the turning portion of the program only to find out that the brakes were still on which let out some smoke. .
Anyone have experience with this happening?

 

[mkd]

perfectly legible :-(

checking out the performance of the pressure gauge after letting machine sit for a while. M110/M109 correctly had no effect on brake pressure. Spindle still unusually hard to turn.
Now it gets interesting. M147 (brake on) pressure goes way up. Then M146 clamp off, pressure drops quite a bit but then only very slowly bleeds pressure. Spindle is still locked even with M109 c axis disconnect.
Explains the smoke, at least.

 

[mkd]

Interesting wrinkle. Disassembled both valves and it's still holding pressure.
I guess those blobs on the schematic are in fact check valves. Your welcome. Lol

 

[mkd]

OK all fixed now. Nothing seemed to be wrong with the check valves. One email to Gosiger later, solution was realized. flow control can get plugged. Orifice of fixed flow control inside manifold i was surprised at how tiny the hole.... .020". A thorough disasembly and cleaning of manifold and a new in line filter seems to do the trick. No more magic smoke.
figured I give the resolution so all those that replied aren't left hanging.
thanks. lol

 

[mkd]

Clearance is clearance, Clarence.