A thread about J-B Weld.

[w.FL.co.]

I bought some of this stuff today, from the friendly folks at ACE hardware. It is for a hole in the catalytic converter, on my truck.

Yea, it will slowly burn away. This is a temp. fix that I have been doing, for a couple years now.

What else can this stuff be good for?

Why not build a boat with J-B Weld?

Well, I can tell you this much, after one days experience; it cures very slowly. About 6 hours ago I mixed up a batch, and it is still soft to the fingernail.

I know that the forum members have some real epoxy smarts. So, can you tell me, what is J-B Weld, and what is it good for?

http://im1.shutterfly.com/media/47b8cf03b3127ccec5f9190d45e600000040O00EcsmbZqxaMg e3nws/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

This is a 45 foot boat. It just looks small because the truck is so large, and I got a better deal buying the epoxy in bulk.

Here is another shot of her.
http://im1.shutterfly.com/media/47b8cf03b3127ccec5f9cf7445f400000040O00EcsmbZqxaMg e3nws/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

Again. What is this stuff J-B Weld, and could it be used to build a boat?

[rddrappo]

It's good on metal, I've used it. The company actually claims that a cracked engine block was once repaired using it and ran fine. Not sure what all it could be used for, but it would be expensive to build a boat with. Smelly too!

[Ron Williamson]

Cracked block?
I fixed one, myself.
The water jacket on an 8N will often crack right by the drain, if it freezes.
Mine did,I Vee'd it out,stuck the J-B to it and hit it with heat gun.
In 3-4 hours I refilled it with anti-freeze and it was good at least until I sold the thing two years later.

That truck must be one of those open pit ore haulers.
R

[Bill R]

Also good for repairing arc pits in FM transmitter PA cavities. The cavities are aluminum and pit badly when something bad happens and you draw an arc. Clean out the pit, mix the JB weld, fill the pit and fair it when cured. Happy transmitter again (assuming you replaced all the other stuff that got blown up)

[kc8pql]

Google is your friend:

JB Weld is a high temperature epoxy resin filled with 40-50% calcium carbonate and 10-20% iron powder. It can withstand constant temps. to 500F and up to 600 F for 10 min. Tensile strength is 3960 psi. It sets in 4 to 6 hrs. and cures in 15 to 24 hrs. When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical. Largest available package is 10 oz.

J-B Weld will not adhere to, or bond well to:

Any flexible rubber surface
Leather
Vinyl
Canvass
Polypropylene plastic
Polyethylene plastic

Looks like you could build a boat with it, but I don't see any reason why you would want to.

[w.FL.co.]

The package says, it is made with steel, not iron. Maybe all that calcium carbonate is a thickener. That, or it is for strong bones and teeth.

If you think that truck is big. Check out this dog.

He is a monster!

http://im1.shutterfly.com/media/47b8cf03b3127ccec5f9bbf9c47300000040O00EcsmbZqxaMg e3nws/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

[rddrappo]

Looks like you could build a boat with it, but I don't see any reason why you would want to.

Because you can...:p

[kc8pql]

The package says, it is made with steel, not iron.
The package may say that but the tech. data sheet on their website says iron powder.
http://www.jbweld.net/techinfo/JB%20Weld-Epoxy%20Steel%20Resin-Overnight-48009.pdf
Calcium carbonate (powdered limestone) is a commonly used low cost thickening agent.

[pipefitter]

I dislike the stuff. I can't count the times a customer has brought in a part needing welding that they didn't try that first with and it is usually cast aluminum. Then the original crack is contaminated with it and it needs to be ground back to fresh metal which kind of destroys the original fitting reference of the pieces and I end up having to build a one off, before and after jig to hold the part in it's proper alignment and it stinks to high heaven when it is burning. It wouldn't be so bad if people knew it's limitations which are greater than it's claims but there is better epoxy putties out there and their answer is usually just to really heap it on.

[Captain Blight]

I've never had ANY luck using JB Weld, If i need to epoxy something I certainly wouldn't make it my first choice. For a while I was using Brownell's Acraglas Gel for repairs of that nature. Works OK but expensive.

[w.FL.co.]

I don't really want to build a boat out of J-B Weld.

It is only, a very provocative premise. Hopefully, I learn something about epoxy today.

Well, when that J-B Weld eventually burns off that catalytic converter, I can replace it with this stuff. Claims to be good to 2000 F plus!

http://im1.shutterfly.com/media/47b8cf02b3127ccec5fb3f7f9c9b00000040O00EcsmbZqxaMg e3nws/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/
The company is VersaChem part no. 83009. By ITW Performance Polymers.

[capt jake]

I typically don't like using JB as the results are sometimes unpredictable. That said, I had really good luck with it on the rear end on my tractor. Somebody had run a bolt into a blind internal boss that was too long. The bolt broke the boss out, causing a mild leak. When I rebuilt the rear end I cleaned the dickens out of the broken pieces and area with brake clean and acetone. I bonded it with JB. I let is cure, re-tapped it and then hoped for the best. ;) It has been holding for a year now.

It is not the repair I would have liked to do, but finding another rear end and paying for the shipping defeated the reason I was repairing it in the first place.

[Chip-skiff]

I used JB Weld to make beercan cookers (below), obviously subject to high heat. It's worked rather well for small applications like that, but I don't think I'd try to repair a cracked engine block.

http://farm4.static.flickr.com/3052/2771237945_a02162a8bf.jpg?v=0

[boylesboats]

I have used that J-B gunk.... Mainly for plugging holes...

[w.FL.co.]

Is the 'beer can cooker' used with Sterno?

[Backfin]

I've made a couple of those cookers with J-B Weld also.
w.FL.co - they burn alcohol. Ultralight.
Chip-skiff -I like your pot rest as it seems to provide a little wind break also. What gauge?

[Gary Bergman]

We had the crankshaft in our Perkins back out an inch, thrusting the lockbolt, washer, etc. right thru the gearcase cover, blowing a two inch chunk of cover into the bilge. After doing the necessary stuff to the crankshaft, I J-B'd the piece back into the gearcase cover, and we ran at least four thousand sea miles until the new cover caught up with me... There's a brand of urethane caulk that works a bit better for cracks and casework...I still carry the repaired cover for a spare

[w.FL.co.]

Happy Thanksgiving Day to all.

I am thankful for wooden boats!

Check out this giant cookie; It is a Mrs. Fields, and it's very tasty. I had a small piece for breakfast.:)

http://im1.shutterfly.com/media/47b8cf06b3127ccec5e2a91ede2b00000040O00EcsmbZqxaMg e3nws/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

[mmd]

The deal with epoxies - all epoxies - is that preparation, mixing, temperature, and application are critical. Follow the instructions to the letter. Be very clean, be very fussy about measuring the two goos, mix 'till your arm is about to fall off then mix a minute longer, and make sure that the surfaces you are applying the epoxy to are surgically clean.

I spent quite a bit of time with epoxy manufacturer's tech reps when I was teaching a college course in advanced composite construction (mostly targeted at aeronautical construction), and we did a fair amount of destructive testing on epoxy adhesives and fillers. The difference in mechanical properties if only one parameter is altered is surprisingly significant.