good insulator that glues good for heatsink TO can pin holes

[coppercone2]

I have a heatsink I made for a TO transistor but I want to glue little tubes into it so that the leads are kept away from the copper.

I can slide tubing over the leads cut to lenght but I thought a better solution would be to actually glue something in there.

What is the best material that adheres to glue the best that can be bought in a rod stock (and drilled) or tube form that I can use for this purpose?

I have teflon super glue primer etc, but its not super necessary here. I thought I can optimize the design by choosing which material will glue the easiest, not necessarily the best insulator.

Part of me thinks that maybe some kinda rough ceramic would be best? The glue should have really good adhesion to alumina I think. But some sort of plastic would be OK too.


These typically annoy the shit out of me and break circuits when the insulator slips out, so I want it in there really good.


Maybe filling them with epoxy and drilling it out would be the best way actually.

[wraper]

How about just using heatshrink tubes. As of adhesive, don't reinvent the wheel and use neutral RTV silicone, preferably electronics grade. I suggest ordering 70x (701-708) from China as those are the only types I know that can be bought in small tubes. I always have a few types of different viscosity stored in moisture barrier bag with desiccant. Don't use random glues on electronics as it will come back to bite you eventually.

[coppercone2]

I want it on the heatsink that I use for prototyping not on the transistor


I think I will just counterbore it ALOT on both sides and then fill it with epoxy and drill it out, it actually seems like a solid idea. Drill it with a fresh sharp carbide drill so it dont get disturbed.

[wraper]

I want it on the heatsink that I use for prototyping not on the transistor

Like spend 10x more time to do that than you'll ever spend by adding tubes during prototyping.

it actually seems like a solid idea.

Sounds stupid.
BTW Soviets always used non-heatshrink plastic tubes and wire soldered at 90^o at the end that prevented tube movement.

I have a heatsink I made for a TO transistor

There are many TO-x packages, the vast majority plastic. So your post did not say anything about it being metal can and heatsink with holes.

[coppercone2]

yeah this heatsink is full of western decadence like not requiring extra work with adding bushings

[coppercone2]

alright I ultrasonic cleaned it for 10 min with alnox then I dried and heated up with a torch, filled the thing with DP270, baked 2 hours and drilled it out with carbide. So long you mind the air bubbles (bit of a pain in the ass) it seems to work OK if drilled with  SHARP (new).

not gonna be dealing with little wire sleeves like some 1984 factory bullshit

[wraper]

not gonna be dealing with little wire sleeves like some 1984 factory bullshit

Why do that "bullshit" if you can do 100x greater bullshit.

[edavid]

You just buy plastic shoulder washers and force fit them into a slightly smaller hole.

If they ever get damaged, spend a few cents to replace them.

https://www.digikey.com/en/products/detail/keystone-electronics/341/16011

[coppercone2]

You just buy plastic shoulder washers and force fit them into a slightly smaller hole.

If they ever get damaged, spend a few cents to replace them.

https://www.digikey.com/en/products/detail/keystone-electronics/341/16011

I considered this but its to-3 8 pin so you need to remove ALOT of copper  and do flat counterbores if you want them to seat in the socket flush