silicone for mounting caps

[sagitt]

hell-o!which silicone is used to set up caps for TW?

[Stevem]

I use the cheapest black automotive silicone gasket maker I can find, if there in a section of the chassis away from the heat of the power tube(s) I use clear bath tube silicone as that's even less costly.

I also use a dab of the black on opposite sides of the power tubes to hold them in if they hang up side down with no retainer clips .

[pompeiisneaks]

Just be sure to get non acid curing silicone, that will etch traces and the like and is bad for electronics. I use GE Silicone II (or known as 2 now?) as it's a non acid curing type.

~Phil

[Stevem]

Yes, if it smells like Vinagar then it's the acid type.

[R.G.]

I once saw an audiophile (that is, hifi tweako) who put auto engine gasket goo RTV in a circle around the diameter of his 12AX7s. He claimed that it dampened tendencies to microphon-icity by acting as a mechanical damper.

Who knows? Could be. Ought to be easy to test if you get a microphonic tube. Test a replacement tube to see if the new tube cures the old tube's audio problem, then treat the old tube with gasket goo an swap it back in to see the difference.

[sagitt]

found this on ebay https://www.ebay.com/itm/Permatex-82180 ... Swatda7GRN

[chaccmgr]

Hi

we build in our company industry computers which are used in rough environments (shock/vibration) and must have a long endurance. For securing components etc. we use Loctite 5145 Tempflex which is dedicated for electronics and is non corrosive and easy to remove in case you have to. It is expensive though...

BR
Robert

[Tony Bones]

RTV comes in so many different forms that it's hard to make general comments. Some of it flows like a slow liquid until it cures, some maintains its shape. The flowable stuff is nice for filling connectors but not as nice for holding down capacitors; it runs all over the place before finally setting up. An important property is how good of an adhesive it is. I would guess that automotive gasket maker is a relatively poor adhesive; it has to be or you'd never be able to remove your valve cover after gluing it down with gasket maker. But I haven't compared it to other RTVs in the same application, so I'm just guessing. It might stick really well to anything other than shiny metal. I suppose you don't want it to be too good of an adhesive if you're holding down capacitors, but I've never used any RTV that stuck to metal or other smooth surfaces as well as I wanted it to (applications different from this thread.)

Having said all of that, I have used Loctite Superflex to hold electrical components down and found it to work well. Available at Digikey, but maybe a little cheaper if you shop around. https://www.digikey.com/products/en?mpart=234323&v=1000