How not to restuff a can electrolytic capacitor.

[@DeadKoby]

I had a Jukebox /w/ old can caps that didn't have a readily available replacement version. I just disconnected the existing old cap from the circuit, and let it stay mounted. A terminal strip and new Radial/Axial caps now do the job hidden beneath the chassis.

[@RuneTheFirst]

When I first saw that potted cap I thought it might be PC-7 or J-B Weld but on continued view it had gray-white sections so it was either poorly mixed or something else was added. The few times I have re-stuffed caps I have used the peel the flange method as I have seen the cut and glue method fail too many times and have run into cases where there is just no room below the chassis to put extra caps. This is especially common with shallow chassis gear like Wollensak tape recorders of the tube era and some car radios. I have gone to hot glue too. Flexible stuff like silicon is too acidic and other flexible or insulating glues are prone to becoming conductive as they age. You can see this in modern gear where caps and other parts were glued to PCBs and failed due to the mastic aging. (It becomes conductive and also eats leads and pcb traces.) Good instructive piece with valuable cautions.

[@justinruth9729]

This guy is talented

[@mrmaxgain]

Is the black epoxy like glass-hard? It maybe ECCO Bond. A two part epoxy that can be mixed to be either like rubber or glass hard.

[@docgonzo1973]

I remember working on some older 80s amps especially Yamaha. That used corrosive glue to hold down the larger heavier components on the board and over time glue would eat the jumpers and resistors off the board

[@fastchevys137]

Good informative videos Mike Thanks for sharing

[@mrdanger4851]

Should I have any consern about lack of heat dissipation when stuffing several smaller caps into a can? Looks like a new problem is being created?

[@mikesradiorepair]

And it would be worse than the capacitors that were in the can previously how?

[@theskett]

Provided the caps have low ESR (i.e., they're good), there should be minimal heat from the caps. I'd be more concerned about the caps being close to a hot output tube, but (like Mike says) just use 105 C rated caps and they should be fine.

[@samhendrix378]

They used black weather stripping adhesive, I have seen this before replacing can capacitors.

[@EssS1226]

good video. I thought you had Alan Alda do the voice over ;)

[@docgonzo1973]

Your right. I think hot glue is the only adhesive glue that's not acidic. I use only that

[@PapasDino]

Hayseed Hamfest builds some nice units for Drake and Collins gear...used them to re-do my Drake C-line and have the 2-line rigs in the queue to be done sometime soon. Not cheap but not exorbitant either...just like a hard drive it's not if the electrolytic will fail just when it will do so.

[@mikesradiorepair]

Dino Papas I have had them build some custom capacitors for me before. What's nice is there is no extra charge for it.

[@martinsmith2903]

Are there any issues with venting if you seal electrolytic capacitors in?

[@BenjaminEsposti]

Probably ...

[@InsideOfMyOwnMind]

Well they are in a secondary containment vessel so you have to ask what you're protecting from what?

[@LarryDeSilva64]

well in the Military ARC-5 Receiver I re-stuffed one of the round can type caps which you will never find off any shelf and when I was done it looked like the original because it just had new caps inside it but I agree if you can find a new can electrolytic that doesn't cost an arm and a leg use it.

[@erin19030]

That's not very smart! A leaky caps is still a leaky cap if put a new one in parallel with it. A leaky cap becomes a shorted cap and now you have a fire hazard. Stuffing caps is ridiculous.

[@theskett]

Good info, thanks very much. I've seen silicone eat through copper wires (my bad, I used the silicone that releases acetic acid when setting) -- but I thought tar was good for 10+kV (per the neon tube transformers that are potted in tar).

[@ronedwards8239]

The twist lock can capacitors still being made for tube equipment are only rated at 65 C.

[@Eric-zi1oz]

I just leave the old caps in and install individual caps on the bottom. So much easier

[@theskett]

If there's space. I like 'Mr Carlson's Lab' approach, of soldering stand-offs to the canned cap terminals, then using the stand-offs to mount the new [and much smaller] caps :-)

[@InsideOfMyOwnMind]

@@theskett I'm mistaken then too. I thought he used terminal strips.

[@tonyp7779]

i cut the top of the can off and throw it away. then i got a nice terminal strip using the can base.

[@dsmiffyrc]

The black stuff looks like pitch, I have seen very old batteries that have been sealed like that. It may be roofing pitch ( still available in the UK) and is full of impurities so is not suitable for this purpose.

[@mrdanger4851]

Sorry I Don't know that's why I'm asking? Thanks for answering my question I'm glad you don't answer a question with a question

[@proten40]

Glad to see you practice safe electronics repair! So is your sidearm a 38 or 357?

[@mikesradiorepair]

proten40 This one is a 44Spl. Have more pistols than fingers and toes. That is one of my daily carry pieces. BIG boom in a little package.

[@christopherdwyer7570]

@@mikesradiorepair They call him dirty mikey. Hack jobs and black boxes. Tell em, "Go ahead screwdriver, Make my pay..." pretty sure Eastwood used a .41 while shooting the movie, either way nice choice of side arm.

[@TechAddictAttic]

Holy crap, didn't even see that there!

[@jimmyfriend532]

Holly coke nail batman !!!! lol, yes I leave my thumb nail long because it makes a great scrapper / pick /ext. Great vid would have never thought to look for re-stuffed caps, WOW !!! I know now...

[@christopherdwyer7570]

I thought the same exact thing !!! Lol Good man!

[@TechAddictAttic]

@@christopherdwyer7570 Me three! I had a coworker at one of my first jobs who kept his pinky nail something close to two inches long. I asked him why, and all he did was raise it to his face like my teenage nerd self would understand... obviously I figured it out in time...

[@squireca]

love the videos and have learned a lot from watching them. But, I gotta ask. What's with the long pinky nail?

[@mikesradiorepair]

+squireca Just don't break off as often as the others.

[@aaronson2540]

It kinda looks burned up!! (Smoked) 😃 Hello Mike cool video.

[@MichaelLloyd]

Maybe the "tar" that they used is thermally conductive epoxy? Nope... should've finished the video first. I like the custom cans or sometimes the current versions will work. But I have restuffed following Buddy's method too.

[@tonyp7779]

i would use electronics grade silicone. not hardware store rtv or silicon. electronics grade silicon does not use acid cure solvent.

[@gregkrobinson]

Those JJ electrolytic cans are only rated 85°C, not 105°C, unfortunately.

[@bulldozerd9]

looks like pine resin

[@nor4277]

I hate restuffing ,just buy some.new.ones solder in place ,once the cover on who sees it,and if someone.open.it up they can tell the new from the old,I hate the purest way of restricting it usually looks worst ,then a nice new part.I like new parts the work better and are smaller

[@erin19030]

Re-stuffing caps ? Get a life !