I bought & installed the 6" riser to do some re-sawing. I installed it
and put on a 1/2" woodslicer blade and it worked pretty well. However,
the next day, the blade came off when I started it it and no amount of
adjusting the wheels would keep the blade from running off the wheels
almost immediately. I figured maybe the bolt had slipped or the washer
had crept ant bent. I adjusted and tightened - no joy. The wheels
seem aligned, no bends.

Could the frame have bent? it's cast Iron... Maybe the blade?

Any suggestions?