Before I got the PDB I had purchased the 31217 Spindle Door Latch Upgrade which for me has always been sketchy. https://www.tormach.com/store/index....kaAgIoEALw_wcB Today the latch opened during a long machining operation, opening the spindle interlock switch stopping the spindle and ruining an endmill. Yeah the spindle stops but the program keeps running. My fix was to drill and tap a 1/4-28 hole thru the latch handle and install a 1/4-28 SHCS with Shear-loc thumb knob. Because of the PDB the Spindle door rarely needs to be opened nowadays and the thmbscrew will make sure it doesn't come open when a program is running.
Don
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