37901 ExtremeHeat High Temperature Resistant Metallic Paste - 3 oz

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!

Someone had drilled holes and used an aluminum bridge, which caused issues with the door closing. I decided to try this J-B Weld ExtremeHeat before spending money on professional welding. It worked nicely to bond the cast iron back together smoothly. Very pleased with the result.

Kneeling the 2-inch adapter into position, I utilized this product as a filler between two components that sit directly in the same cup without a divider. I wrapped a stainless shim around it to ensure a snug fit and secured everything with a clamp. So far, it handles thermal changes pretty well. I plan to see how it holds up after a week. I'm pleased with how helpful it’s been so far. An AI tool mentioned it has good adhesive qualities and durability, although I haven't tested those features myself yet.

If you use it for deep hole filling it takes more than an hours to set, it is strong but not that strong you can brake it with your fingers, if is applied on hot surfaces it tends to shrink.

Used it to fill in rusted out gap on an oxygen sensor bung that was leaking air into the 02 sensor and causing false reading. That was causing the check engine light to come one. You really have to prepare the surface. I used a brass wire brush to scrub out loose rust of which there was plenty. I was wearing chemistry lab goggles and my face was covered with rust afterwards. Then mix the stuff. Yes it is one use you are mixing an epoxy glue. I used nearly all of it anyway. Mix it thoroughly and let it set up, it thickens fast and is easier to lay on when thick. When you first mix it the stuff is quite runny. I spead it on with a wooden coffee stirrer stick. This was a tough application because it was the exhaust underneath the truck so gravity is working against you. I managed to get one layer on and laid on some more. The putty is kind of self leveling which is good. It kind of drips but by that time is so thick it still stays in place, mostly. The O2 sensor was still attached so I was repairing the bung around the gasket of the O2 sensor and trying to pack the stuff into the gap. Then I let it sit for the full 24 hours before driving, to allow it to cure fully. The truck has 2 catalytic converters and the original owner replaced the passenger side one more than 50,000 miles ago so I know the other one is getting to the end of its life. But getting air into the 02 sensor due to rusted out fitting contributed to the problem. So far so good I drove it 3 days no check engine light and the exhaust putty is holding up so far.

kanon

Amazing result. Used on an old gas oven door. Unable to get parts to repair handle but this product did the trick. Very pleased.

I bought it to fill the gap developed in high pressure vessel..it is very good and handy in such situations..highly recommend.

Reparer un coude d’echapement sur un bateau le temps d’avoir la piece de rechange.

I wasn't expecting much, but JB delivered. No solvents, great repair to my exhaust silencer. Top marks.