Renovating old electrolytics - UK Vintage Radio Repair and Restoration Discussion Forum

Alf · 24th Jun 2005, 10:44 pm

With restoration in mind and trying to keep original components at least visually perspective, I've been tempted to attempt some form of 'repair' to a couple of old Radiospares 32µF caps pictured, they were from a Philips 170A chassis and both of them are o/c. Problem is, I've opened up the cans on electrolytics before, never giving a thought to them, just disposing of them after, I've been reading other posts suggesting the installation of a newer component in the can. Has anyone got any tips as to how to get around breaking the seal from the aluminium can to the terminals with minimal damage?

Station X · 24th Jun 2005, 11:40 pm

Alf.

Don't try to break the crimped seal. Even if you manage it you'll never be to pull out the guts and seal it up again.

Instead make a cut round the case with a junior hacksaw or a pipe cutter. I find the latter is best. Place the cut in a place where it can be concealed by a mounting clip, label, or a piece of thin aluminium glued over the join.

What I do is to take a piece of plastic drain pipe about 1 1/2" diameter and the same length as the can and make two longitudinal cuts in it, removing the piece between. The gap can then be closed to make a pipe with external diameter equal to the internal diameter of the can.

Push this pipe into the bottom of the can. Fit the new guts, bringing their leads out through small holes close to the existing tags. They can then be soldered to the tags OUTSIDE the can.

Test for leakage and capacitance before pushing the top of the can over the pipe. Glue the join.

Incidentally were Radiospares components ever used when building new sets? I thought they were only used for repairs.

HTH.

Graham.

Alf · 25th Jun 2005, 2:23 pm

Ok Graham, thanks for the information, I don't have a 1½" pipe cutter at the moment but I'll make a point of obtaining one and give it a try.

Quote:

Incidentally were Radiospares components ever used when building new sets? I thought they were only used for repairs.

Yes, as far as I'm aware they were used just in repairs and not new equipment, I think that this demonstrates that the radio has been serviced and well maintained in times past.

Alan_Douglas · 25th Jun 2005, 3:17 pm

Some crimped cans can be opened by working slowly around the crimp, removing the terminal plate and guts. If these photos display properly, here's how I did it for three twist-prong electrolytics in a 1950 Zenith TV:

http://antiqueradios.com/albums/Misc/RESTUFF1.jpg

http://antiqueradios.com/albums/Misc/RESTUFF2.jpg

http://antiqueradios.com/albums/Misc/RESTUFF4.jpg

http://antiqueradios.com/albums/Misc/RESTUFF5.jpg

24th Jun 2005, 10:44 pm	#1
Alf Hexode Join Date: May 2005 Location: Wigan, Greater Manchester, UK. Posts: 479	Renovating old electrolytics With restoration in mind and trying to keep original components at least visually perspective, I've been tempted to attempt some form of 'repair' to a couple of old Radiospares 32µF caps pictured, they were from a Philips 170A chassis and both of them are o/c. Problem is, I've opened up the cans on electrolytics before, never giving a thought to them, just disposing of them after, I've been reading other posts suggesting the installation of a newer component in the can. Has anyone got any tips as to how to get around breaking the seal from the aluminium can to the terminals with minimal damage? Attached Thumbnails

24th Jun 2005, 11:40 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Renovating old electrolytics Alf. Don't try to break the crimped seal. Even if you manage it you'll never be to pull out the guts and seal it up again. Instead make a cut round the case with a junior hacksaw or a pipe cutter. I find the latter is best. Place the cut in a place where it can be concealed by a mounting clip, label, or a piece of thin aluminium glued over the join. What I do is to take a piece of plastic drain pipe about 1 1/2" diameter and the same length as the can and make two longitudinal cuts in it, removing the piece between. The gap can then be closed to make a pipe with external diameter equal to the internal diameter of the can. Push this pipe into the bottom of the can. Fit the new guts, bringing their leads out through small holes close to the existing tags. They can then be soldered to the tags OUTSIDE the can. Test for leakage and capacitance before pushing the top of the can over the pipe. Glue the join. Incidentally were Radiospares components ever used when building new sets? I thought they were only used for repairs. HTH. Graham.

25th Jun 2005, 3:17 pm	#4
Alan_Douglas Retired Dormant Member Join Date: Nov 2003 Location: Cape Cod, Massachusetts Posts: 59	Re: Renovating old electrolytics Some crimped cans can be opened by working slowly around the crimp, removing the terminal plate and guts. If these photos display properly, here's how I did it for three twist-prong electrolytics in a 1950 Zenith TV: http://antiqueradios.com/albums/Misc/RESTUFF1.jpg http://antiqueradios.com/albums/Misc/RESTUFF2.jpg http://antiqueradios.com/albums/Misc/RESTUFF4.jpg http://antiqueradios.com/albums/Misc/RESTUFF5.jpg