How to hold large capacitors in place

Parts Express sell 1 3/8" mounting brackets, and you can find other sizes at Digikey and other online stores. I highly recommend you use them, as a large capacitor coming adrift can cost way more than you save by hot-gluing the thing. I was a repair tech before getting becoming an engineer - you should see the damage a loose cap can cause. It's not worth the trouble to futz around if you can get the real thing by return post.

Hot glue never holds, I've even tried cleaning the spots with acetone. :eek: ;)

If you don't have the metal clamp rings, make some! If I need to strap caps flat to a chassis I just cut a strip, bend it around the cap and bend a tab on the end (after cutting to proper length), drill for the screw and tighten it down.
With some fancier tin-snip work you can cut wings on it to mount the cap vertically through a hole, recreating commercial items.



diyAudio Moderator Emeritus
2002-10-24 10:19 pm
Sch3mat1c said:
Liquid nails eh? Does that end up something like the goo around large caps on PCBs (like computer PSUs etc.)?

Yup. It's particularly suitable for caps laid down at chassis folds so that you can get two beads holding it. If you look at the bottom of my Eico HF87, you'll see a bunch of photoflash caps tucked in just this way. And it seems to be rugged- I just disassembled a preamp I build in grad school (25 years ago) and had to chisel the caps out.
Maybe, but it is also a type of sealant used on metal roofs and gutters between sheets of metal. It remains waterproof forever because it doesn't harden and flexes with thermal expansion.

I used a tube to glue 12 caps together as a kid. Mabe a hella mess. I thought it would hold great after it dried because it was so sticky....but it never dried. I used a gallon of laquer thinner to reclaim my caps.

I later learned what its intended use was.
I have to mount a lot of medium sized caps as compact as possible and like to discuss the idea I had to do this.

The construction is made of hexagonal bolts size M4, some made of steel for stability and others made of polyamide for insulation. For electrical connection and mounting of the caps I use metal sheets 2mm strong, most likely stainless steel. The caps are pressed against a sheet of foam to dampen vibration. All insulating hex bolts are female types and have the metal threaded bolts screwed into.

What do you think about the idea?

I'm not good at mechanical design but from my point of view it's a cheap, easy to do and clean solution. It might not survive being dropped hard. For the case someone drops the amp I'm in serious trouble anyway.


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