What does epoxy NOT stick to?

[Steve]

I need to repair a particle board desk where an "insert nut" pulled out of a recessed hole. An "insert nut" is one of those toothed monsters that screws into the wood, then you screw a bolt into it.

I plan to put the insert nut back in the hole and use epoxy to fill the void where the particle board crumbled. The epoxy will also hold down some splintered laminate. I'd like to put in the epoxy, then use a clamp to apply pressure with boards on each side of the hole.

Of course, I need something to put between the epoxy and the boards that is immune to the epoxy. Is there such a substance? I usually use plastic wrap or aluminum foil when I do this with carpenters glue. Am I SOL here? Thanks.

[DJ Delorie]

Wax paper.

[dadiOH]

Plastic like that from garbage/refrigerator bags. You would be better off with a T-nut if fittable.

[Leon]

I have tried 2 brands of 5 minute epoxy when gluing rare earth magnets to flat painted aluminum, no luck.

[Lee Michaels]

I just can't help myself.

What you need Leon, is an aluminum magnet.

I know, I will keep my day job.

[Leon]

;~) That is correct. I have been trying to hang self made full window screens to the other windows to filter summer time sun light. I attached a magnet in each corner of the screen and then attached another magnet to those magnets in each corner, apply the epoxy to the outer magnet and stuck it up to the aluminum window frame and held them in place for 10 minutes. This worked great for 1 day on two occasions.

[Joe]

Easy enough: mix two parts unobtanium with one part unaffordium, pour into mold, place in oven, bake until solid.

[DJ Delorie]

Magnets should be sanded to provide mechanical adhesion as well as chemical, and you probably should sand off the paint where the magnets will stick to.

For shiny surfaces like those magnets, try either superglue or the two-part glue they use to attach rear view mirrors to windshields.

[J. Clarke]

Personally I think I'd put a plug in it then bore the plug and screw the insert into the bore.

That said, in answer to your question waxed paper works. If you have a couple of boards that have been painted or polurethaned or coated with something else smooth and nonporous, a few coats of a good grade of paste wax (Butcher's Wax works, so does Johnson's, avoid silicone car waxes) on top of that will also do the job. Polyethylene sheeting will also work, and then there's the whole gamut of commercial mold-release compounds.

[DerbyDad03]

Epoxy will not stick to anything coated with Vaseline. If you can get the repair section horizontal, I would do this:

1 - Coat the threads of the T-Nut and a bolt with Vaseline 2 - Screw the bolt into the T-Nut to seal off the T-Nut threads 3 - Drop the T-Nut into it's beat up hole and get it level. Support it with tape if required. 4 - Pour some epoxy, preferably with some filler added, around and over the nut. 5 - Let it set overnight - If the T-Nut is in the corect position, you really shouldn't need to clamp it. 6 - Unscrew the bolt

Here's the epoxy system I use for a lot of projects. You can see a container of filler in the background. I buy it at a local marine supply store.

[charlie]

rough up each gluing side, then use ge silicone 2. apply magnets to each piece, use tape on the vertical side, and let sit for at least 24 hours before applying the screens to the windows.

you can use the extra strength hot glue too.

if the magnets are too strong, then they'll pull their opposite partner out of the glue. you probably want small ones. i use 1/4"x1/16" thick ones for holding glass to steel using hot glue.

regards, charlie

[Phisherman]

Have you tried JB Weld for the magnets to aluminum? For the epoxy to work remove the paint.

[Pounds on Wood]

Lot's of things already mentioned. I'll add, that low density polyethylene plastic works great for working with epoxy as well as most adhesives. That's the stuff that milk bottles and the cheaper gallon water bottles are made of. Just cut up a couple of milk jugs and you'll have some nice sheets to use as mixing pallets, spatulas, whatever. I've not found any common adhesive that will stick to it, and it FREE.

[Dave Gordon]

plastic works great for

bottles and the cheaper

you'll have some nice

common adhesive that will

[Father Haskell]

Use a magnet cup. Once you drop in the magnet, it's not coming out.

[DerbyDad03]

Be careful here - too much epoxy sitting in a plastic container for too long will melt it. I mixed some West Systems in a plastic cup once and set it on the workbench for too long. It melted one side of the cup, which tipped over and dumped the rest on the workbench.