Restuffing & Testing Electrolytic Capacitors

[@ohger1]

Restuffing cans is the best option. I restored a 1951 Andrea 16" TV that had nine (9!) cans. Imagine putting terminals and external caps for nine cans inside that already crowded chassis. 30 years after I'm gone, some guy will be thanking me for not turning that chassis into a train wreck. Other than the plastic caps replacing the paper ones, it looks like it did when it left the factory and still matches the picture in the SAMs.

[@ronniepirtlejr2606]

She's a Beauty!👍 Great job re-stuffing that & good idea of what the hose clamp! I read somewhere that the capacitors with the (M) were made by Panasonic. Probably a sister company to the name you said? Very good capacitors!

[@DVRproductions52]

Thanks for the comment. I would put all your test eq. on one grounded circuit and only connect your device under test to the isolation transformer. Yes, Uncle Doug is a great teacher and he's the guy who really inspired me to do my own videos and build my own guitar amps.

[@LouinVB]

Good effort. I cut the can above the phenolic using a pipe cutter so as not to disturb the terminal lugs or the can crimp. I then use a heat gun to heat the can until the guts come out. The heat will not transfer to the base because its been cut from the can. The guts can then easily be removed from the base, base drilled for cap leads. When i reassemble ill use silicon on the inside and a strip of heat-resistant aluminum tape on the outside. It results in a much cleaner base, tabs, and lugs.

[@SDsailor7]

How do you remove the clear protective plastic sleeve that surrounds some of the old capacitors without destroying it? Thank you

[@oldavguywholovesRCA]

On that paper cap some people save their old wax from their old caps and use it to fill in the ends. I started a collection of old wax but threw it away as my hot glue gun works really quick.

[@tariqelageli6552]

Good tutorial! I found that placing my MLCCs in warm water (just over what is comfortable to touch) helps with freeing the glue at the bottom. The glue I've seen used all the time also dissolves quite easily with 99% IPA, so injecting some in the can can be used as a last resort..

[@julian65886]

You sound just like Uncle Doug, nice video!

[@DVRproductions52]

Wow, thanks for the compliment! Uncle Doug is my fav.

[@RadioRanger-po4hj]

Thanks for your Video! I'm presently restuffing the electrolytic capacitor on my "All American Five" Zenith, your video was affirmation I'm doing it right. I was questioning myself because after I reconnected the e-cap back into the radio it shorted out, killed the rectifier tube and the 220 om. resistor. Now I can focus elsewhere for the short.

[@DVRproductions52]

Nice going man! Thanks for the kudo's. Good luck with the restore.

[@bryandowdey1779]

Very interesting and useful video.. Thanks for demonstrating!

[@DVRproductions52]

You're welcome and thanks for watching.

[@ohger1]

I take my Dremel with a high grit stone and grind down the bottom of the can until I expose the steel ring. I then pull that out and remove the guts reusing the phenolic base. I reassemble by putting some two part black epoxy on the inner lip and placing the phenolic and steel ring back in place.

[@bofor3948]

Put a suitable sized Jubilee clip (hose clamp) round the top of the capacitor and tighten to protect the aluminium from the side cutters. It will also help keep the top round as unlike the sheet metal held by hand there will be no gaps and it won't slip. Ah! see you saw that idea later in the video. One other thing you mentioned you have a polishing wheel. If you can substitute that wheel for a plain steel wheel or if you have a lathe you can set up a support bar to help hold the can tight against it while pressing and turning against the wheel to press the peeled metal back smoothly. I have stuffed several this way with good results.

[@DVRproductions52]

Ohhhwww... I like that idea. Can't believe I didn't think of that when I was just inches away from a whole drawer full of hose clamps! -- Duh.

[@therealjammit]

My method is to destroy the phenolic brown disk on the bottom that has the terminals on it. I pick out all the phenolic bits and remove the old capacitor guts. This leaves me a hollow aluminum can. The steel ring is then removed by slightly folding in half an pulling it out (it can be flattened easily later if you don't go crazy and fold it completely in half). By using a smooth metal rod (screwdriver shaft) I can slowly un-roll the crimp on the aluminum shell from the inside. After stuffing new caps in the shell I make a new phenolic disk with circuit board material (I can recycle old circuit boards by cleaning off the resist and completely etching or scraping off the circuit traces). I then drill and shape new holes for the solder lugs and solder the new caps, install the new circuit board, add in the steel ring, and use the same round and smooth metal rod from the outside to re-roll the crimp (a little hammering helps). I also like to solder the common cap wires somewhere to the steel ring for a solid connection to the chassis.

[@DVRproductions52]

Cool idea Jammit! I'll try that next time.

[@SDsailor7]

What does voltage loss indicate? And should there be none? Very interesting video. I am trying to learn how to stuff a capacitor and also learn about capacitors. Thank you

[@SDsailor7]

​@@DVRproductions52First video I have seen that explains the ESR in relation to the life of a capacitor. Thank you👍

[@SDsailor7]

​@@DVRproductions52what size resistor should I use for a 400v capacitor to discharge it safely? Thank you

[@SDsailor7]

​@@DVRproductions52Would it be easier to cut a hole big enough on the bottom to remove the "guts" and then just drill the holes for the capacitor leads? Or would that be more difficult to do?

[@shanejohns7901]

This thing is more like a grenade than a capacitor! It's a bit crazy to see a capacitor that large yet without any of the stress grooves in it that give away to let it explode more safely out of the top.

[@WestviewChurch]

These types almost always vent out the bottom around the phenolic. Sometimes you'll even see a small hole or thin spot where the electrolyte or gasses can vent.

[@oldavguywholovesRCA]

If only I had a lathe, that would be an interesting challenge to unroll the crimp and reroll it when finished.

[@DVRproductions52]

That IS an interesting idea. I wonder if some attachment could be made to use a drill press?

[@edwardkrarup8816]

I am trying to fix a bang and Olufsen tuner amp, and I need to replace some of the capacitors they are really old, there is one big one which is. Wicon Electrolytic cap 3000uf 70 v. DCW red positive type Kl 2404x2. And two Wicon Electrolytic cap 3000uf 25v. DCW Type Kpl 242x1 Plain negative is there alternatives I can use would you know which ones they are. I would appreciate your help.

[@DVRproductions52]

Hi Edward, I sure wouldn't know but you might try searching Mouser or Digi-Key. Maybe someone else out there would know...

[@edwardkrarup8816]

@@DVRproductions52 thank you for your reply I will have a look

[@DVRproductions52]

Both use the same kind of search engine which is a little hard to get used to but one you do, you can find just about anything.

[@fldave612]

Can the printing on the wax caps fade when you heat them?

[@DVRproductions52]

Oddly enough, no. They must have used some really good ink back then.

[@OneDamNote]

Thank you for sharing.

[@DVRproductions52]

You're entirely welcome!

[@HowardJohnstone]

Why not just disconnect the capacitor and leave it in place. The modern replacement is very small and can be placed under the old one. It is normally not possible to increase capacitance due to valve limits.

[@DVRproductions52]

I've done it both ways as well. I just wanted to show how the actual "stuffing" process goes if anyone's interested in keeping the absolute vintage properties of the radio or amp. In the case of my Zenith Trans-Oceanic, there was absolutely NO room underneath one of the cans to put any additional components so I was was forced to "stuff it".🤫

[@wraitheful]

I like everything except the use of foam which off gasses over time and creates it’s own set of nightmare problem (see all Hammond organs made after ‘64) I’d try a more durable filler, felt being a perfect replacement.

[@DVRproductions52]

That's true. I have a lot of foam products that are turning back into dinosaur fodder after a few years. Felt would be much better.

[@ericschulze5641]

Why not remove them from the circuit and put the new ones underneath, where they can't be seen

[@DVRproductions52]

That's my preferred method also but some restoration "purists" like to keep everything as "stock" as possible so I made the video for those who would like to keep the caps wired in as new. Also, there are times (like restoring the Zenith 7G605 Bomber) that there is just no room for one more component under the chassis.

[@ericschulze5641]

@DVRproductions52 because when showing off our collections we take them apart and show people the innards

[@bigio5936]

Hi, this is not the way to restuff old capacitors: this is the way to destroy them,I have no channel on youtube, but if you want I can send to you images where I can show the way I usually restuff old capacitors on vintage electronics. Actually I am recapping a old Mcintosh MX110 (the Medium Version, without 6D10 Tube 1962/1963) and i'm not destryng the can.

[@WestviewChurch]

Would love to see them!