Hello Tom,

My Craftsman hand saw started doing this same thing last year. I think
a brake went bad!? But I am able to change blades. I have a "nut" on
the rear of the blade that I have to hold while turning the front arbor
screw. This keeps the shaft from turning. I hope this is helpful.

Mike in Ohio

Tom wrote:
Black & Decker miter sale model 7715 type 3.

I bought this saw at a garage sale. the seller cut a board, said it
needs a blade. But, I can't remove the old blade. The armature of the
motor turns when I try to turn the blade nut. If I "jam" the blade so
it can't turn, the armature still turns. How do I lock the motor to
remove the blade?