Somebody somewhere in the comment section (I think on Marcus’s blog) expressed dislike for resin stabilized wood along the lines that it is the same as making the handles out of plastic. I disagree. Stabilized wood is a pain to work because it behaves like plastic in that regard, but it does not look like plastic and neither does it feel like plastic in the hand – it feels like wood. And as I was working on this project, I found out that it even sounds like wood – stabilized pieces give out very nice clonk-clonk when hit against each other. I think it might be possible to make musical instruments out of it, but I won’t try.
However, before said wood reaches its desired stabilized state, I have to work with epoxy resin. Lots of it.
I hate it.
It is gluey, it sticks to absolutely everything and it is transparent, so when it drops somewhere it is difficult to see in time. Tools and surfaces need to be cleaned with paper towels soaked in denatured alcohol, which is not cheap and the fumes do not smell exactly delicious. And the work needs to be done fast, because if the epoxy gels, it won’t soak into the wood no more.
With my macgyered vacuum pump I have reached a vacuum of 0,2-0,3 bar, which was sufficient for extremely porous wood, but might not be sufficient for this. Applewood has very small pores and is very hard, even the very decomposed pieces were still harder than for example poplar or basswood. So I have decided to bite the bullet and buy a small, cheap vacuum pump in the hope that it will work better. And it does – and it does not.
Even with my poorly sealed pickle jar, I have easily reached vacuum 0,6 bar within a minute. The wood released so many bubbles that the resin developed foam head like beer.
However, the pump also got very hot after a few minutes of running, which made me a bit worried. My macgyvered pump was a bit cumbersome and awkward, but overheating was completely a non-issue. I am not so sure about this one. I hope it does not burn out before I at least get to sell some knives.
Overheating aside, the wood soaked up the resin very nicely and although I have only used clear resin, it developed very nice and pleasant colors. The resin would cure over time at room temperature, but it is possible to speed up the curing by heating it to 60-80°C. So I did that the next day and I baked the pieces for two hours, after which I could appreciate the nice clonk-clonk that I was talking about at the beginning.
I have also approached the issue a bit more scientifically this time and I have weighed all the pieces before and after. Here you can see the results.
This made me very happy with the results. The relatively healthy wood has gained approx 30% in weight, the not-very-much rotten root wood doubled its weight and the more decomposed wood has almost tripled its weight. All pieces of similar size weighed approximately the same after the stabilizing process, irrespective of what wood they were made of. And finally, all pieces when put in water either sunk completely or just barely floated with 99% submerged. So even the relatively healthy wood should be soaked up with resin to sufficient depth.
Now that the wood is stabilized, the only thing that is left is to psych myself up to go into the freezing workshop and finish the knives. Which includes first a bit of grinding and drilling, and then a lot of gluing. Even more fun with epoxy awaits, hooray!