PDA

View Full Version : Release agent for JB Weld?



radkins
08-04-2011, 02:56 PM
I need to make some metal part impressions in a woodworking fixture that will use JB weld as part of the structure, it's lightly loaded so strength is not a problem. What can I use for a releasing agent to prevent the metal parts from being glued to the fixture? I can't find anything locally and ordering online is not an option because I need it now and can't wait on it, any suggestions?


I tried car wax and it helped but still the parts were stuck fairly tight, the little bit of releasing agent I had left from a gunstock glass bedding kit worked great on the first two parts but there was not nearly enough of it to finish the job.

brian Rupnow
08-04-2011, 03:23 PM
Vaseline----------------

CCWKen
08-04-2011, 04:10 PM
A little late now but I keep a couple of cans of mold release in stock at all times. I use it for my zinc castings but it also works for rubber, silicone and ceramic. And it works for dry lubing. It's a boron compound in a carrier that evaporates in less than a minute. Boron nitride is one of the slickest materials on Earth.

You might run up to the hardware store and see if they have dry lock lube in a spray can. That would probably work.

AiR_GuNNeR
08-04-2011, 04:57 PM
I've pulled out my tube of silicon grease from my fishing kit as well. Sporting goods stores carry it in the fly fishing department. it's used to keep dry flies floating.

HighWall
08-04-2011, 05:13 PM
I need to make some metal part impressions in a woodworking fixture that will use JB weld as part of the structure, it's lightly loaded so strength is not a problem. What can I use for a releasing agent to prevent the metal parts from being glued to the fixture? I can't find anything locally and ordering online is not an option because I need it now and can't wait on it, any suggestions?


I tried car wax and it helped but still the parts were stuck fairly tight, the little bit of releasing agent I had left from a gunstock glass bedding kit worked great on the first two parts but there was not nearly enough of it to finish the job.

Some people use cooking spray with success. My father in law, a riflesmith of some note, uses Johnson's Past Wax exclusively. I really like the spray on mould release sold by Brownells for use with their AcraGlass products. Very convenient and it's never failed to release as long as I make sure not to allow a mechanical lock by accident.

Highpower
08-04-2011, 05:39 PM
A good coat of wax followed by some PAM cooking spray. Works better than one or the other alone IMO.

The PAM makes for a good (cheap) anti-spatter spray for welding too. :D

A.K. Boomer
08-04-2011, 06:38 PM
Now that were on the JB weld topic --- whats a good dissolving agent?

Evan
08-04-2011, 07:04 PM
Polyepoxide (epoxy resin) has one big weakness. Acetone. You can also use flourine gas but I recommend against it. :eek:

clutch
08-04-2011, 08:56 PM
Kiwi neutral shoe polish. Works great, you can fill holes that might cause an interlock. I bedded my Savage MKII rifle using Kiwi as a release agent a few weeks ago.

CLutch

gunsmither
08-04-2011, 09:09 PM
Johnson's Paste Wax. Works great with any kind of epoxy.

radkins
08-04-2011, 09:18 PM
Thanks, I put this on hold until tomorrow when I can make a trip out to buy something, living out in the boonies like this makes it difficult to just run out to the hardware store. I think the paste wax and shoe polish sounds good because I will need to fill some small voids with whatever I use.


Thanks to everyone for the suggestions.

Orrin
08-05-2011, 12:27 AM
All the suggestions are good. Here's another: Hold the object over a candle and it will soon be covered with carbon soot and a wee bit of unburned candle wax. Be sure to keep the object moving over the flame in order to get uniform coverage.

I've not tried it, but an acetylene flame (no oxygen) is sometimes used.

JB-Weld, being a bit stiff when it is applied, tends to push away some release agents and bond to the base material, in spite of one's efforts.

Orrin

gambler
08-05-2011, 12:29 AM
I've used pam while bedding rifles and also while making fiberglass repairs to boats. works great. nothing sticks to pam, ask the cook in the house.:)

darryl
08-05-2011, 02:01 AM
One product I've used many times as a release agent is- skin oil. If I'm laying up a little epoxy job and I want to keep some part from sticking when I know the epoxy is going to go there where I don't want it- I rub my forehead up into the hair line and get a little 'mold release' on my fingers, then apply it by rubbing it on. It does work, maybe not for everything -do your own test.

Krunch
08-05-2011, 02:11 PM
Any wax should work fine.

ckelloug
08-05-2011, 05:12 PM
I use the Ease-Release 200 agent from www.mann-release.com for the Epoxy Granite Samples I cast. It is a silicone base release agent. They have some others that aren't silicone based. Unless it's something that just truly doesn't matter, spending $10 for a can of good release agent probably makes more sense than improvising: especially if you need quality.

As for Evan's comment on acetone, it may have some effect against epoxy hardened with aliphatic amine hardeners but as you get into epoxy hardened with cyloaliphatic amines, aromatic amine and anhydrides (usually billed as high temperature epoxies), it is almost completely useless. Acetone is a good cleanup solvent for uncured epoxy but for cured epoxy, N-Methyl Pyrrolidone, Dimethyl Formamide, and hot (100C) Dimethly Sulfoxide are much better solvents. N Methyl Pyrrolidone is commonly used in industry to deflash molded epoxy parts. Of the three, Dimethyl Sulfoxide (DMSO) is by far the safest for removing epoxy provided you aren't sniffing the fumes or spilling it on yourself and due to its use in quack medicine, DMSO may be available at your local healthfood store. I've used all three but DMSO is probably the only one people will be wanting to sell you as an individual.

--Cameron

clutch
08-05-2011, 06:33 PM
I recommended kiwi neutral which works fine, I have also used PAM cooking spray to epoxy bed a M1 Garand. I used modeling clay to plug any holes that I wanted to stay clean.

In the future, I'm going to stick to Kiwi since I liked it better.

Clutch

radkins
08-05-2011, 07:40 PM
I picked up the Kiwi polish while at the grocery store this morning and it worked really good, I was going to get both the polish and the paste wax but the store did not have the wax.

winchman
08-05-2011, 08:58 PM
I tried to dissolve some JB Weld by soaking it in warm acetone for several hours, but it didn't even get tacky.

metalmagpie
08-05-2011, 09:32 PM
I built up a gear tooth using JB Weld once. I made a mold from JB weld on a good part of the gear. I used nothing at all except soot from an acetylene flame as a release. I had to tap it with a small hammer to crack loose, but it came right off in one piece OK. Then I sooted that part up and used it as a female mold to form the gear tooth. It also broke right off. So I know sooting works.

I have also tried a wax-based rust preventive spray-on similar to Boeshield. It worked about the same as sooting.

metalmagpie

davidwdyer
08-05-2011, 09:42 PM
There is a product called "Attack" that will probably attack all kinds of epoxy.