Thermal insulating pad between heat sink/PCB

[Potato Cakes]

Hello,

Going through Colin's guide for fixing up a TAC Scorpion PSU, it shows that a thermal insulating pad is added between the large heat sink and the PCB. I have been looking around for thermal pad, thermal insulating pad, thermal insulating sheet, etc., and I haven't been able to find something that is being used in the guide. I have found small thermal conducting pads for regulators and larger and expensive sheets that were also the same really thin material used for regulators, but no thermal insulating sheet big enough to be used for the PSU's heat sink. If someone knows what the thermal sheet used in the guide is called or has a part number/link to share, would you be as so kind as to reply with it here?

Thanks!

Paul

 

[CJ]

https://www.digikey.com/products/en/fans-thermal-management/thermal-pads-sheets/218?k=thermal%20pad

 

[Potato Cakes]

Thanks for the link, CJ.

All the products listed show as thermally conductive, which is where I am getting hung up. Granted the original design has the heat sink mounted directly on the PCB with no thermal separation. My thought is that I should find a material that minimizes transfer between the two items as there isn't any reason I can think of to want to transfer heat to the board. For this application does this really matter?

Thanks!

Paul

 

[Potato Cakes]

Here's a link to the guide that has a picture of what I'm after:

https://redirect.viglink.com/?format=go&jsonp=vglnk_154912823806113&key=27f13a138b9c18bbb26d1b79059da4a7&libId=jrnqy52s01000n0n000DAanjkuan5&loc=https%3A%2F%2Fgroupdiy.com%2Findex.php%3Ftopic%3D59170.20&v=1&out=http%3A%2F%2Fwww.audiomaintenance.com%2Fdownloads%2F750_series_to3_socket_modification.pdf&ref=https%3A%2F%2Fwww.google.com%2F&title=Another%20Amek%20Tac%20Scorpion%20overhaul!&txt=Colin%27s%20TO-3%20socket%20fix.

I tried just posted the photos but I keep getting an HTTP Error 500. Maybe something funny is happening with site again.

Thanks!

Paul

 

[JohnRoberts]

Picture works for me.

That looks like just an electrical insulator that is temperature resistant, not a thermal conductor.

JR

 

[Potato Cakes]

Weird, I keep getting the issue when trying to add attachments. I'll try later.

Indeed, I wasn't trying to find a thermal conductor, just something thin enough to still allow the legs of the regulators make contact to the underside of the PCB and insulate from the heat sink. In my search for an insulator that is not conductive I have been surprisingly not finding anything that fits the above requirements.

Thanks!

Paul

 

[Potato Cakes]

I found this. It should be fine:

https://www.amazon.com/Black-Resistant-Silicone-Rubber-Gasket/dp/B06WCZD1LZ


Thanks!

Paul

 

[Newmarket]

I think the problem was just the terminology.
I'd take a "thermal insulating sheet" etc to refer to a material with good heat conduction whilst electrically insulating.
I can see that it doesn't necessarily read like that - it's just the usual terminology ime.

 

[Potato Cakes]

The answer to original inquiry:

https://uk.rs-online.com/web/p/plastic-shims/0770793/

Thanks!

Paul