How To Remove a Metal Can From a Tube/Capacitor

Glad to see of your getting it up and running. Believe it when I say All us are delighted for your success.

Thanks Rod, got it done per your instructions--no problems. It fired up and sounds pretty good. Not getting anything sound from one of the electrostatic speakers (going to double check my connections). The FM band does not play has loud as the AM band. The glow tube (tuning eye) comes on and works but not very bright.

Yes. You can solder the negative ends of the new electrolytic caps to the the old ground tab or to any nearby existing ground points under the chassis. No real need to cut away the old ground tab of the original filter cap can. Just cut or disconnect the original positive lead wires coming out of the can as Cliff said. You don't want to leave them connected although you might run into this kind of thing in other old radios where someone was in a hurry and just bridged a new cap across the old one.

I might add that when working on an AC/DC transformerless type of set you might find that the B- (one side of the power line) is connected to the chassis OR that it is floating i.e. all the B- connections are tied together but insulated from and not directly grounded to the chassis. Usually here you will find a capacitor (.02uF to .05uF) in parallel with a high value resistor (470K Ohm for example) that connects the signal grounds of the front end (tuner) to the B- connection.

Your choice, just make sure the canned cap leads are cut.

Guys--replacement with new caps is going well, per your suggestion, I am putting new caps below and leaving the can in place to maintain the orginal look. Question concerning the ground from the cap can. 5 wires below the can are attached to the tab coming from the can. Can I solder the new caps to this ground or do I need to cut the tab from the can (taking the ground away from the can) making the can totally dead? Thanks.

I would just add the replacement caps to under the chassis if you have enough room and disconnect the wire to the old can. It looks like the cap isn't a USA product, so it may be hard to find an identical replacement.


EDIT: I moved this topic because it wasn't about crystal radios, but about tube capacitors.

Electrolytic caps are not forever. With tie strips in place the next cap changout will be easy, that is if caps are still being made...

Chas

I guess it depends on if you want the under part of the chassis to look original.
     I usually just put in three separate caps under the chassis. If you do that , make sure the polarity is correct.
  If you want it to look original , restuff the can you have . Dan in Calgary

Here is the link for the  photos. Thanks.https://servimg.com/view/20094971/2

Guys, thanks for your reply. I found out that it is a Multi-Section Capacitor that has a nut holding it in on the opposite side of the chassis. Phil's Old Radio site helped with that one. Trying to decide should I get another M/S cap or go with 3 separate ones on the bottom of the chassis.

Could you submit a picture of the can so we can tell what you are dealing with? Aluminum, copper or steel can?

Rod  WB6FBF

Tubing cutter...

OR

https://hayseedhamfest.com/

Hi,

I have been trying to remove the metal can covering a tube/capacitor. I have tried to twist it and rock gently back and forth with no luck. Any tips/advice would be appreciated. Thanks.