G+_Michael Maxfield Posted May 6, 2014 Share Posted May 6, 2014 I know it's not a Twit KH project, but perhaps someone in the army knows the answer. I'm looking for a source of multiple pieces of rubber gasket seals for a triac in an RD-91 package so that the top end of the tiac is mounted through the hole on the outside of a weathertight box with the top end and heatsink exposed to the elements. Believe it or not, I've had no luck finding one, not even in a TO-3 form (not really wanting to cut the hole though. A salesman at Arrow Elec told me it wouldn't even be worth their while calling in an engineer to figure it out. Sent me to te.com which tried to be more helpful but none of their stock gaskets looked like they would work. I must be missing something here, because I'm quite sure this is not a unique task for a triac meant to be mounted through a hole. Perhaps there is another package designation with the same dimensions. Link to comment Share on other sites More sharing options...
G+_Paul Miller Posted May 6, 2014 Share Posted May 6, 2014 Could a rubber O-ring work? If so you could probably get one at an auto parts store or a home center. Link to comment Share on other sites More sharing options...
G+_610GARAGE Posted May 6, 2014 Share Posted May 6, 2014 Generally, components aren't stuck through the case. It could lead to the parts being damaged. But what you could use is rtv silicone. The stuff is used all the time in cars. Also, if you hole is really tight, you may be able to use an o-ring. Link to comment Share on other sites More sharing options...
G+_David H Posted May 6, 2014 Share Posted May 6, 2014 Typically, this would be mounted on the inside of the metal box (in my experience), if the box is not metal, then really it would have to be mounted on a heat-sink for proper cooling/grounding. You can also make a gasket out of a tire inner tube from a bike. Link to comment Share on other sites More sharing options...
G+_Dave Salaman Posted May 6, 2014 Share Posted May 6, 2014 A gasket would defeat the purpose of the heat sink. You need metal to metal contact to conduct heat away from the component. With a little thermal grease to help. Link to comment Share on other sites More sharing options...
G+_Michael Maxfield Posted May 7, 2014 Author Share Posted May 7, 2014 I beg to disagree with Bob, Dave and David. The RD-91 is a through the hole mounting package. (Can bee seen in the tech data for a BTA40-700B on the Digikey site as one example. The rubber gasket would not defeat any heat sinking since it would be on the tail end of the package where there is minimal surface for sinking anyway. The following link is a collage of pictures of the setup and one such gasket which I can't find a source of. https://plus.google.com/105519828970827041030/posts/gvidZsBghpD Link to comment Share on other sites More sharing options...
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