Just filled a hole about the size of a framing hammer bash an inch deep into a board. I had some System 3 “grizzly glue”, amber polyurethane, water accelerated, thick honey consistency Gorilla type glue. Worked fantastic. Mixed it up just like Bondo on a piece of wood mixing in water exactly the same as mixing the catalyst into Bondo, then smeared and gobbed it into the hole, it expanded just like the foam blow cans at Home Depot but more dense and no voids, none, it set up, surformed, sanded and glassed over under an hour. Really worked great. Too bad about the amber color but this repair was non see thru.
My latest love is a foaming PU glue that sets in half an hour!
If you mist water on, this stuff starts bubbling away in about 3 -5 minutes!
And, the beauty of it is, it just happens to be a very similar colour to the Paulownia wood I use.
...about the size of a framing hammer bash ...
Next time you piss off your girlfriend, make sure the tools & boards are far apart, ok?
I had great results in a similar situation. Foam core wood skin board from popular manufacturer. Board went into the rocks and had a crack/depression about the size of a quarter and 1/8” deep or so. I used the largest crack to insert a dental tool and pry the dent back out some. Mixed some gorilla glue with a little water in a Dixie cup, sucked it into a syringe and filled the hole. Taped it over and held my finger over the hole while it expanded. Boy did it expand! It filled the hole, pressed the dent back out most of the way and seeped out the cracks. I kept pressure on it till it stopped expanding and continuously wiped any seepage away.
After it cured I sanded it all flush, covered with a patch of glass and finished the repair as usual. My kids art pens weren’t the perfect shade to match the grain but all in all it’s about as good as I had hoped. Agree it’s not the right color for white board repairs but for wood or anything that will be colored it works really well.