Glue / Epoxy for adding stability to electrolytic caps?

Hi,

Sometimes in repairs of older stuff I end up having to use radial electrolytics in place of axial ones. I try to use axial when I can but sometimes it's tough to find high quality axials in the rating I need.

I've seen other people use hot glue or epoxy to stick them to the PCB for additional mechanical stability. Was just wondering if anyone has a recommendation for the "best" glue or expoxy, something that will hold up over time.

I've never tried epoxy to glue caps, but i think it is not the best choice. If you have to repair, epoxy will be very diffcult to remove.

I've made the best experience with hot clue. It works very well and can easily be removed, if a repair is necessary.

In my experience, hot glue doesn't hold well enough.  Maybe I've just got the wrong hot glue, but it seems that PCBs and capacitors are both too smooth to get a good bond.  Epoxy, on the other hand, might be a bit too permanent.

I've recently started using double sided adhesive foam tape under capacitors.  It's quick and clean, and nothing has fallen off yet.

Steve.

double sided tape seems like a decent solution. epoxy seems like it might be a bit much, don't want someone to be cursing me in 20 years when these things need to be recapped again.

I've used hot glue for years to glue down caps in speaker crossovers.  If it is not holding enough, maybe the glue gun needs be be a bit hotter?

Cheers,
Zach

Hot melt...

JR

Or drill a couple of holes in the board and use tie wraps or solder a bit of wire round.

Works well for older tube gear and DIY - which is where you commonly find big electros, but not so well for tight PCBs.

I work in the aerospace electronics industry and we use RTV adhesive (aka silicone bathroom chalk) to hold down large components like electrolytic caps in equipment subject to high vibration.  It holds well yet is removable with some effort in the event that the component needs replacing in the future.

I've used  clear silicone glue with great results. holds well and is just as easily removable.

Wallybob said:

I work in the aerospace electronics industry and we use RTV adhesive (aka silicone bathroom chalk) to hold down large components like electrolytic caps in equipment subject to high vibration.  It holds well yet is removable with some effort in the event that the component needs replacing in the future.

Click to expand...

This has been S.O.P. in the repair business for many years and works very well !! 

This goes back to the 1970s..

GARY

if you use RTV, get the electronics grade stuff, the regular stuff emits nerve gas which can damage pc board traces and other metal in the general area,

Wallybob said:

I work in the aerospace electronics industry and we use RTV adhesive (aka silicone bathroom chalk) to hold down large components like electrolytic caps in equipment subject to high vibration.  It holds well yet is removable with some effort in the event that the component needs replacing in the future.

Click to expand...

pucho812 said:

I've used  clear silicone glue with great results. holds well and is just as easily removable.

Click to expand...

Normal silicone is not good for electronics, because it contains acid. After a while it speeds up the oxidation of copper. My uncle mad some electrics which he sealed with silicone. After one or two years, he opens the rack and everything was oxided. He hast to make the electrics new. Maybe there is special silicone for aerospace electronics, but silicone for the bathroom is not a good idea.

+1 electronics RTV
-1 silicone tub and tile caulk

mjk said:

+1 electronics RTV
-1 silicone tub and tile caulk

Click to expand...

Another vote for RTV.

-a

Dow Corning ® 3145 Silicone Adhesive is the stuff.

I,ve used sticky sponge pads before - like found on nylon pcb standoffs. Make sure the caps are firmly mounted - found them good for both radial 'lytics as well as axial 'lytics and big film caps.
Sure - if there is heat they will dry out - but so does the joint of hot glue.

There is a special adhesive glue that exist for this purpose. It will glue components, wires etc... to a PC board without damaging the board if removal is required. Have a look around at Digikey, mouser or so...

"There is a special adhesive glue that exist for this purpose"

but you do not know it's  name,

gee thanks! 

best  non post of the year, ???

there is a gold mine in the hills, but i  do not know where it is,

E6000 aka shoegoo. It dries harder than silicon glue, keeps the components from vibrating which could eventually cause leads to break. I just repaired a tube amp that failed because of hot glue. A pre-amp plate resistor got too hot from being covered in hot glue. 

+1 ShoeGoo/Goop

FWIW, Silicone caulk is conductive until COMPLETELY dry/cured. (Makes an interestingly stinky fire.)