I’ve recently used this product to repair a substantial amount of wood rot around our home. In reality, the best way to deal with wood rot is to replace the wood with new material. J-B Wood Restore comes into play when the wood rot that you find will be A) Structurally insignificant or B) a MAJOR pain that you want to delay for a period of time until you can deal with it by replacing material. The trick is knowing when you stop chasing rot and go with the replacement.
The half dozen or so places I needed to address were sized from a quarter to the size of a baseball. I used a Dremel tool with a high speed cutter to get into the spots and remove all the rotted wood. Then I applied a wood hardener (and not included with the kit) to seal the wood against further rot. The epoxy putty is a two part compound that you mix together in a 1:1 ratio. It’s pretty easy to mix together, but it helps to add a bit of water. After around 20 minutes, it cures up incredibly hard, yet can be worked with regular woodworking tools. With a wood chisel and a bit of 50 grit sandpaper you can make it as smooth as the surrounding woodwork. A bit of primer and paint, and it was like new.
There are quite a few other products in this class of items, but they either require special applicator guns or are insanely expensive. With what I needed to do, I really couldn’t justify spending hundreds of dollars on the stuff that the pros use. Especially when, with wood rot, you’re just kicking the can down the street for a while until you’re ready to replace material.
(This is the same product as Elmer’s Structural Wood Repair – I’m not sure who is the original manufacturer of the stuff.)