J-B Weld 37901 ExtremeHeat High Temperature Resistant Metallic Paste - 3 oz

This stuff is great! I patched to holes in a catalytic converter and despite the intense Heat, the product has remained intact! It's easy to mix and apply, and dries rather quickly.

Used this to patch a crack in my muffler on my 150cc scooter and so far it has worked perfectly! I live in North Texas and it's June, so it's pretty warm out even in the evenings, so I had no problems with cure time. Started to harden within a few minutes after application.I did have to mix up the product pretty well before it was ready, but that was easy. It doesn't come with something to stir/apply it, so I used a small spatula that came with another weld glue product.Seems to be holding well even with high temperatures. If it fails I will update this review, but so far so good!

I have used another one of their products that is intended for a similar use. That is more like toothpaste than a tube so it is somewhat easier to apply because you can put it on the tip of your finger and place it where need be. This comes in a extremely small jar. You have to stir it before using it so the only thing I could use was a small screwdriver. Trying to get it in on my manifold around all the obstructions It was so watery that it was difficult to not have it completely run off my finger before getting it to where I needed it to be. It's not completely liquid but it's not the paste either. Not really satisfied with how little of it you get compared to let's say the paste that the same manufacturer sells. One thing that I understand but I don't like is that you cannot apply heat to it for 24 hours. So with the amount of heat that would come off of a manifold obviously you really do have to wait It's not like an exhaust pipe that would be cooler. So the negatives were: amount given, size of container, product consistency. Waiting for it to cure so I cannot give a review on quality

I purchased this item to repair an ash fettle in an old Vermont Castings wood burning stove, and it completely exceeded my expectations outlasting an entire season of direct fire contact. The fettle was cracked into two pieces and a prior owner had drilled two holes on either side and tried to connect it with an aluminum "bridge." The repair interfered with the door closing, so I needed to seamlessly "weld" the two cast iron sides back together. Before going through the trouble of taking it to a welder and paying to have it repaired properly, I took a chance on this J-B Weld ExtremeHeat.I used a Dremel tool with a fine grinding stone and cleaned up the two broken faces, along with about 1/4 inch of the area on either side of the crack. Following the advice of another review, I then took a cotter pin, stuck it into the chuck of my battery powered drill, and used that to thoroughly stir the J-B Weld in the container (this is a one-time use container... once opened and stirred, use it and toss the rest). After stirring for just under 2 minutes, I immediately applied it to the two surfaces, pieced them together, and then spread a little more on either side to ensure a supported bond. I then set the item on a flat piece of cardboard to cure for 2 days. (NOTE: you have to support the joint while curing, because the J-B Weld provides no structural support until completely cured. While wet, the item will just fall apart again if the pieces aren't otherwise held together.)When it was done, I replaced the fettle and lit the first fire of the season (crossing my fingers at the same time). Several months and probably 100+ fires later, the piece was still holding strong like the day I put it in. The fettle sits right against the fire, and many logs have rolled into it while it was extremely hot, with no noticeable damage whatsoever. I would absolutely recommend and use the J-B Weld ExtremeHeat again on future projects. As long as the proper preparation is done, and you follow the instructions, it's an awesome product!

Follow the instructions and this works well.I has a gas stovetop grate crack and the replacement price was $150 — no way! It was for the middle grate that I rarely use, so it was worth trying this.My 1st attempt I didn’t sand the connecting pieces well enough, and the second time I let it dry in a position where weight was helping the bond for 24 hours. That clearly made the difference.