shannon, send a pm to lonecomic he's a ex slingerland employee, he'll have the answer for you

Screw the knob as far into the shell as possible, even with your other hand holding the muffler tight to the shell. Then you have enough threads exposed to retap the shaft...

The knob will then easily come off...

Thanks everyone for the suggestions! I don't have any means on hand to retap the shaft, but I've pm'ed lonecomic as suggested. I'm also going to try the suggestion of using another knob, if I can locate one.

Thanks everyone. This is my first real attempt at a restoration, so I may come back for more advice, particularly once I start trying to restore the wrap.

The knob is made of chromed brass. It will be destroyed by trying to run it over the stripped threads of the shaft!!

Those are two different mufflers you have pictured. I assume it is the pic of the snare. vadrums is correct, you have to get a die with the same thread pattern and just clean up the threads at the end.

Guys. I think you might want to just put some good lube on the threads. Put it on the threads on both sides of the tube nut. You want to use a thicker lube and work it into the nut and threads well. Once you do this, it will come off fairly easily. This happens on pretty much all of these. Slingerland and Ludwig are built very similarly and both do this. The oxidation plays a game with removing these and you have to overcome that. Once you work in the lube WELL, it will come off with just your fingers. I can post a video if you need, but it's pretty much straight forward. DO NOT USE tools on this stuff. It will damage them if you're not careful.

I deleted my bad idea.

me too.....

This happened to me with a wfl tone knob. I eventually just muscled it loose. Just when your by the drum give it a few shots.