Greetings fellow tube-heads! I am restoring a 1938 Stromberg-Carlson model 325N chairside wood radio for a friend. I need to get the radio chassis out in order to have access to the front of the cabinet. I cannot get any of the three bakelite knobs off. I put a bit of penetrating oil on each shaft with no results. I'm afraid to use a screwdriver, etc. to try to pry them off for fear of damaging them or the cabinet. Does anybody know how to do this safely so I can have access to the entire cabinet?

Regards,
Chris Kennedy

I hope someone knows a neat trick because I'm afraid of what might have happened. I'm pretty sure these knobs are just supposed to push on and pull off.

You might want to ask your friend if he knows if anyone glued on the knobs to keep them from falling off. I've had bakelite knobs where the little internal metal flat spring got lost and people glued them on (OK sometimes JB Weld really isn't your friend). Not good news when you need to get them off. If that's the case you might be in the market for some reproduction knobs.

Curtis Eickerman

two forks at 180 degrees to each other used as pry bars. felt or soft wood to prevent damage behind forks.

Curtis; S. Jacke: Thanks for the tips....If the 2-fork attempt doesn't work I'll look for some knobs that match as close as possible.

Chris Kennedy

Spray behind knob with WD 40, let sit overnight. Wrap a shoelace around shaft behind knob and pulllllll.

It's nice, but too damn expensive. A real shame.

www.stewmac.com/shop/Tools/Special_tool ... =3&xsr=766

John S.

A modification on the two fork method is to use a pair of old fashioned can/bottle openers (church keys). Sometimes they are stronger and might provide more leverage than forks. As mentioned don't forget to cushion/protect the face of the radio.

If you can get to the backside shaft, I'd try some paint stripper, let it run into the knob. It won't hurt the bakelite. It might just soften the glue enough to release it.

Next, have the knob ready to pull of with the forks or pry method. Hea the knob quickly so as not to let the shaft get hot too. You shouldn't melt the bakelite, it's pretty substantial.

When it is very hot, try to pull up. The softened glue might just let go.
Good luck!

Gary: Thanks for the tip....I'll give it a try....heat and solvents should work or at least greatly increase my odds for success.

DCK

What a project made of this. Loosen the screws first. Some C-10 might work.

You're quite welcome DCK. Heat will usually make most glues soft, the luckily the knobs are bakelite, which can withstand the heat. You are sure they are bakelite, right?
Good luck.

Isn't C10 Naptha?

Ola and guten tag! I managed to get some penetrating oil to the backsides of the knobs using a small syringe a couple days ago. I'll try the heat w/the puller and hopefully they come off. The knobs are definitely bakelite.

Donald Kennedy

Just kidding around, the C-10 is a explosive charged catapult used on carriers for aircraft launch.

Double post..

Thanks Hoffies, I kinda thought that it was some kind of pyro-related device, or substance I was thinking of C4 and didn't want to do too much of a search for C10

One site did mention an aromatic solved called C10.
I think Don will get the knobs off using everyone's suggestions.. Oh, I did use your "shoestring" method more than once for a stubborn knob. Thanks.

Thanks to everyone for the tips!

I was stationed on the carrier USS Carl Vinson (CVN-70) from 1985-89 and was a Reactor Operator....loved the job but not the military head games/mumbo-jumbo....had a great time, tho'! Wish I could travel like that again.

It's nice that catapult technology progressed from extremely dangerous explosives to steam....When on my RO watch the airedales complained alot about not having enough steam for their launches....always adjusting the CSC (Catapult Supervisory Control) for them.

Again, thanks again for all the tips.
DCK

And ?????

OK the suspense is killing me. Did the knobs come off?

Curtis Eickerman

OOPS! I forgot to include that data....have a nasty rhinovirus (cold). I haven't tried yet....been letting the penetrating oil soak for a few days plus it's been crazy-buzy this week. I will update next week.

DCK

Greetings everyone! I broke down and purchased a knob puller. It worked wonderfully on the 2 smaller knobs but wouldn't fit around the large middle 2-piece knob. I used two small nail/tack pullers w/cardboard between them and the cabinet to prevent damage. They came off but the larger portion broke in two. A little epoxy should remedy that. All the knobs were definitely glued on. The penetrating oil soak helped alot.

RCARADIOLA