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HELP!!!!! Non-melting adhesive?? Answered

Does anyone know an easily accessible adhesive that will neither melt or conduct electricity?? I'm using it for the cotton candy machine, which by the way, is really close to completion!



11 years ago

Everything melts. It depends on the temperture. There are silicone that are good to very high temps. They use RTV siilicone to bond the space shuttle tiles. Home depo may have some versions of it. Do a google on "high temperture RTV". Epoxy will work too, there is tones of them out there that go high temp. Like I said, what is the temp.? All glue are non-conductive in general, it will depend on how thick it is applied. It sould not be depended as the sole medium for electrical insulation. Since in home applications, the bond line thickness is rarely controlled. all it takes is one contact point between the two adherend. For sealant purpose, use the RTV for sealing engine gaskets, in automotive store. As for food safety, the main worry is outgassing of the glue. Heat it up a few times, the smell will be gone.


11 years ago

Silicone. I wouldn't want epoxy on a food product (but then, silicone would tend to be less rigid. But it sticks to ANYTHING and is good to quite high temps...)

westfw is correct. silicone is the highest temp rated cheap/common glue. most epoxy and super glue will disintegrate in the 300-400F range. silicone is good to 600F or so. there are plenty of more specialized glues (including some epoxies) that go very hot though, so if you need them just look in www.mcmaster.com

I'm not sure exactly how hot this thing is getting, though. The silicone would be sitting directly on nichrome wire, with 5A @ 28V going through it. For now I'm using concrete, but I'd like to replace it with something a bit lighter. I made about a quart of cotton candy today, in my unique projects class. Just a btw ;)

if the nichrome is your heating element and it is getting near red hot, then you reallly want a mechanical attachment, not glue.

If the purpose is to seal the contact points of the element, consider using ceramic clay. The heat will harden it into glass making it a permanent insulator.

Tell me if I'm wrong, but I've always had the o that epoxy melts when heated, kind of like a hard plastic.

In my experience epoxy when hardened doesn't melt. It may char and otherwise decompose - how hot will this get? Which parts do you want to fix together?

I'm feeding the leads from the heating element that will probably get up to 400 degrees through the aluminum plate under it. (One of the leads is the actual nichrome wire because I had to cut the element in half). I ended up making my own crimps by cutting 1/4 copper tubing in half, then wrapping a few layers of Teflon tape over that. It seems to be holding up for now, but I'm worried that it might eventually melt off. Also, I'm using the concrete to insulate the actual nichrome wire from touching the inside wall of the aluminum plate ( only about 1/4 inches of it). Is this a good idea, or should I replace it?

See if you can get some heat-resistant compound. There are pastes and such for repairing auto-exhausts, wood-burning stoves and similar. I don't think concrete is a good idea at this temperature. Glass fibre matting may be a good one too, and fairly easy to use(?) As for the Teflon-tape, if you mean 400'F it won't melt, but since it's not very sticky it could come loose(?)

We (my cousin and I) decided to use some teflon tape and fiberglass tape. We added a bit of quick-dry cement to the mix as well =P

Thanks for your help though!

Any form of Cyanoacrylate (Super Glue) is resistant to heat and non-conductive. You can also get quick hardener at most any hobby store to use it as a sealant. This is what I used to use to seal component calibrations ( potentiometers and variable capacitors).

epoxy, any of the forms. cyanoacrylate tends to be brittle, if you add some baking soda it becomes gap-filling.

I wouldn't say any epoxy. but jb weld, non toxic, high temp ,non conductive.