The old Sears molding heads which I think were actually Delta Rockwell heads came with a very thick spacer that you had to put on in order to move the head away from the arbor enough that the 1" wide molding cutters wouldn't strike the frame. It is about the same diameter as as the blade washer. I don't see why you couldn't and I've thought a few times about trying to set up a shaft with circular saw blades and spacers that could cut a finger joint in one pass. Some of the old sawmill gang saws used the same idea to make 2" lumber. They maybe still do. I don't know if there is better technology for that yet or not. They used the head rig to make a cant and shoved the cant through the gang saw. That may be how they got the nickname spaghetti mills.
The only problem I see with using regular washers is that the hole for a 5/8" bolt is pretty sloppy so the washer would sit off center on an arbor and would be a little out of balance. Enough to matter? i don't know. If you had that spacer from a molding head it would be close to the right size. Sears did have tongue and groove cutters for that head. I have one and Corob cutter still makes them and cutter sets and they interchange with mine. $17 a set last I looked.
The only problem I see with using regular washers is that the hole for a 5/8" bolt is pretty sloppy so the washer would sit off center on an arbor and would be a little out of balance. Enough to matter? i don't know. If you had that spacer from a molding head it would be close to the right size. Sears did have tongue and groove cutters for that head. I have one and Corob cutter still makes them and cutter sets and they interchange with mine. $17 a set last I looked.
