J-B Weld 40001 Wood Restore Liquid Hardener - 16 oz by J-B Weld

This is a good product, worth Five (5) Stars in some situations, and for others, requiring a deep penetration, it may be a 4...BUT, I rated it 3 Stars here hoping folks would find this note. the point here is simple: This is NOT an acetone based product, even though previous reviews say it is. Apparently it was acetone based several years ago, but the product was changed recently. It is not, for example, in a metal can, like you would expect for acetone. And, the label actually says "Clean up with Acetone". But , it is a water based product. It is white like Elmer's Glue, but different. It soaks the wood with polymers, creating a hard texture. Acetone penetrates the wood with a plastic, which I find is harder than this product creates. But, with acetone there are bad fumes....which may mean using this product is a better choice.

This product is no longer acetone based. It works ok, but not like the original product. This is still advertised as the original product in the metal can. It now comes in a plastic bottle. Doesn't soak in as well and definitely doesn't harden as well. It "stabilizes" the wood, it's just not the same. The acetone based stuff would harden wood so well that you could drill it and sand it, don't plan to do that with the new formula.

I replace badly rotted siding and window sills, but on difficult surfaces with less rot, I pressure wash the rot out and use this after it dries out. The three options for wood hardener appear to be, a two-part epoxy, a water-based acrylic and a solvent-based plastic (which this and Minwax hardener is). I picked this because the acetone base soaks in and dries quickly and drives residual moisture out. It is toxic, so that and the drying action hopefully will kill bacteria or fungus to prevent further rot. To be on the safe side, use rubber gloves and try to avoid the fumes (same solvent as finger nail polish, so it stinks). Wipe runs off paint quickly, as it will soften it. After it dries, I cover the small voids with latex acrylic caulk, and larger holes with Bondo from Walmart auto dept. Yeah, some claim that epoxy hardener and filler is the way to go, but it is expensive for big jobs, and I'm cheap.

I had some dry rot in my home's siding and some wood cockroaches had burrowed into the wood behind a small section of the siding. I scraped out all of the soft stuff and brushed the Wood Restore over the damaged wood. It was rock hard when it dried. The new siding is a much better quality, but I don't think anything will be burrowing into THAT section of wood again, even if the buggers get behind the siding. It makes me feel a lot more secure knowing things are sealed up and hardened.

The product is difficult to shape when your applying it to the damaged location.Conversely, it’s quite easy to sculpture after it cures. I found myself displeased w/the outcome therefore I ended up milling the pcs in question w/wood however it took longer but got better results.

This is a quality product but I wouldn't buy mail order again. About a fourth of the bottle had leaked out into the box and box had saturated and dried. The lid seemed tight but maybe not secure or maybe the container is not intended to be shaken and rolled and is not secure by design. The remainder of the liquid worked perfectly as intended and saved me a lot of money on repair instead of replace.

Used this on non-structural water not-very-damaged unfinished 2x4 and waferboard in attic - made both darker and left a hard shiny surface after dry, and not sure if it really "soaked in". Probably OK for where the damage was and what was damaged. Have used other more expensive products that definitely "soak-in" before drying (but are more difficult to apply) and still leave some hardened material inside the wood. I tried this because it was less expensive and had the JB name. Still have some left and will use it for other repairs, but might prefer the "soak-in" kind for more damaged wood.

Works very well and drys quickly. Be careful though, it will stain any painted surface turning it white or shiny and you'll have to repaint. Definitely use a disposable brush to apply and a small cup, it will make your bristles stick together after but you'll have much more control over the liquid

It works great. Beareful fumes. Do not apply in realy hot weather. Keep an eye on it. Besides the warning its realy good and you get more oz. than some other company's offer.

Very thin consistency so be sure to use a foam applicator or something similar to avoid drips & wastage. Really soaks in fast so doesn't cover as much area as one would expect so have extra on hand for project as will probably run out.

Worked great! I used this product to preserve tree bark on a live edge slab. It really did the trick.

Didn’t restore full strength but apparently encapsulated all the wood-rot. Looks good enough to cover up with caulking and paint; just don’t expect it to be like new.

It is magic, I did not have to replace my water damaged plywood flooring. Brushed it on and let it harden over night, did a light sanding and the vinyl flooring was ready to install.

Product is easy to apply. You will sacrifice a small paint brush. Dries rapidly. Only downside to me was the cost per volume.

Used in a area on the deck I was rebuilding that was hard to get to...stops the rot!