Restuffing Cap Cans

[passaloutre]

I find myself in a situation where I’d like to reuse and original Mallory cap can as a replacement is not available for this amp. The amp has had axial caps installed as replacements for the originals, and is working fine, but the original cap can is still there just not hooked up. I usually think this kind of adherence to vintage looks is kind of silly in a circuit that only I will look at, but I find myself wanting to try it anyways.

I know that I’ve seen topics on this before, either here or another forum, but Google is coming up blank today. Does anyone have any good resources or tutorials (videos or otherwise) on restuffing a multi section cap can?

[neskor]

https://groupdiy.com/threads/how-to-restuff-an-electrolytic-can-capacitor.51368/
https://www.tdpri.com/threads/restuffing-multi-section-can-capacitors.404905/

[blackcorvo]

I once made a multicap out of an old can stuffed with modern caps:

https://drive.google.com/drive/folders/1TfZsk_ZNZgJu-4Lk6RprkXQVmpBfqZxw?usp=drive_link

[kagliostro]

May be you can be interest on this item

https://grangeramp.com/product/multi-section-capacitor-board/

Franco

[passaloutre]

Unfortunately that PCB is the wrong size, if I were willing to drill holes in the chassis I’d just get the 1-3/8” cap can that is available from AES.

However it does look like Hayseed Hamfest actually has the 1” cap I need: https://hayseedhamfest.com/collections/misc-audio/products/3-tab-20-10-10-450v

[kagliostro]

Unfortunately that PCB is the wrong size

OK, so



https://groupdiy.com/threads/how-to-restuff-an-electrolytic-can-capacitor.51368/

Franco

[scstill]

I have previously left the can for looks
and added the modern caps inside the chassis
Here is an example https://stillampd.com/harmony-h303

[shaun]

I have restuffed a couple of cap cans, and although some may empty out easily, the ones I had (old mallorys) were a complete pita - messy, smelly, and easy to damage the thin aluminum can. But maybe I needed more experience at that. I used a drill bit to chew out the old gunk. Doubt I'll do it again if I can help it.

It was pretty easy to install new caps inside, once I cleaned them up.

[kagliostro]

To empty the old cap (after you open it, no previously)


Try to put it in a water can and boil it


Then try to empty it when it is still hot


Franco

[scstill]

is the stuff inside the old can toxic?
https://thedhtsstore.com/blogs/news/37118465-vintage-components-oil-filled-high-voltage-capacitors-and-dangerous-pcbs
I recall once trying to melt the wax and stuff out of a couple vintage axial coupling caps.
It was totally bad experience and tough to think of doing again.

[PRR]

e-caps use Boric Acid plus very small amounts of "additives".

You probably won't die, you can itch real bad, especially in the eyes. Use mask, goggles, gloves, wash real well.

PCB oils and their bromine kin are a very different thing, rarely found in domestic gear, both carcinogenic and toxic, also messes with biochemistry. Part of what Pete Seeger was singing about on the boat.
https://en.wikipedia.org/wiki/Polychlorinated_biphenyl
https://en.wikipedia.org/wiki/Polychlorinated_biphenyl#New_York
The school I worked with had a big campaign to remove or isolate all PCBs and to label all buildings' PCB status.

[scstill]

from that article: "In the United States, PCB production was banned in 1979 and most other jurisdictions followed within a few years."

And much of the stuff I see is in old radios (30's 40's) and amps (50's 60's).

I just got an old Leslie 25 (60s?) that's gonna become a guitar amp some day. Its got a tall can that if needs to replaced will live as a dead tower for looks (clipped leads) with the new modern caps in the chassis, not in the can

[scstill]

from the wikipedia article on PCB/New York
"Pollution of the Hudson River is largely due to dumping of PCBs by General Electric from 1947 to 1977. GE dumped an estimated 1.3 million pounds of PCBs into the Hudson River during these years. The PCBs came from the company's two capacitor manufacturing plants at Hudson Falls and Fort Edward, New York."

[rafe]

I too disconnect the cap cans and replace beneath the chassis, if I can't get the can easily or affordably. I did do that with one of my amps a long time ago, but I don't remember which one it was now, If I sold it, they might have thought it was suspect and replaced it??

[scstill]

For some reason I cannot sell my amps :-(
So I just build another shelf :-)

[rafe]

I haven't sold one for many years, but i haven't ruled out the possibility, of course there are those I wouldn't want to part with.......

[tdvt]

I too disconnect the cap cans and replace beneath the chassis, if I can't get the can easily or affordably.

I have a vintage Princeton Reverb that had issues with the currently available cap cans, so I made a shouldered plug from aluminum to fit in the hole & used that to anchor a small cap board, using radials, on the inside of the chassis.

Not vintage looking inside but more functional & no holes drilled.

[bmccowan]

tdvt - what problem did you have with available cap cans? I've found the current CE cap works and fits fine.

[tdvt]

tdvt - what problem did you have with available cap cans? I've found the current CE cap works and fits fine.

I had sections go out in two, plus the price has gone WAY up. And a JJ can is too big to fit (realized that after I ordered one)

This solution worked well, & you could even break up the ground points between nodes if you wanted to (I didn't)

[bmccowan]

Thanks - that's bad news about sections failing. PR is the only amp that I have recently used a CE can. I regularly use the 2x32 F&T can adding other  caps as needed. I have had good luck with that can, but their options are limited. Weber has multiple options, including a 4x20, and used to have a really nice blue color. The white they now use sticks out like a sore thumb IMO.

[passaloutre]

Ooh, I hadn't seen the Weber ones! Looks like they have a couple that would have worked fine for me. I ended up going with one from Hayseed Hamfest, which was a bit more expensive, but they let you specify exactly the sections that you need.

[bmccowan]

Although I have bought several Weber speakers, I often forget to look to them for other components. The quality of what they offer varies widely IMO, but before they went to the white color (I know this seems petty) their cap cans worked fine for me.

[HotBluePlates]

... had issues with the currently available cap cans ...

tdvt - what problem did you have with available cap cans? I've found the current CE cap works and fits fine.

I had sections go out in two ...

A tech I trust on another forum had a number of problems with CE Manufacturing cap cans.  If you watch their videos, the "swaging" of the cathode ends that make the common-negative connections can be flaky if the cap wasn't made just-right.  And apparently he got several that weren't made right.

The 2nd video below shows the cathode-swaging.

 

[scstill]

Here is my just finished Leslie 25 with replaced filter caps inside.
More at this - https://el34world.com/Forum/index.php?topic=30951.0

[kagliostro]

Some years ago, at an HamFest, I got a few octal NOS male sockets

The intention was to use for 9pin to 8pin converters and as base for homebrew Multi Cap Cans (adding an aluminium or copper pipe as body

I was thinking to put a dedicated 8 pin sochet on the chassis and to mount the DIY Multi Cap Can unit on it

Franco