Wood finish to handle high temperatures (not turn cloudy)

finishingheatvarnishingwood

I'm building a mobile bench top for my home brewing system. The system will be all electric powered by heating elements actually in the kettles (think hot water heating elements). When this type of system is built it is not uncommon to just set the vessels on top of a wood surface. I'm only giving this info up front so you know that any heat involved is being transferred from the vessel itself, not exterior burners.

I'm planning to use 3/4 ply as a substrate, then some leftover unfinished 3/4 hardwood flooring (oak, likely) to cover the surface. Many simply use dimension lumber for the top, then leave it unfinished but I'd like to make it a bit more attractive.

Two of the vessels will reach a max of 170*, and one will be in the 205-210* range, and I'd guess 95% of that temp will transfer to the wood surface. From what I've read, Urethane varnish is the most durable, Spar Urethane seems to be what is commonly found. I think anything oil based will be better than something water based.

Does anyone know of a finish that will work in these conditions without going cloudy after some heat? I don't need much for color, I just want to protect the wood from moisture and preserve it. This bench will spend it's life in the garage as well so UV isn't really a concern. If the answer is simply "no", I guess I can leave it unfinished, but I'd like to do something. Even linseed oil if nothing else.

Best Answer

I would not use a urethane finish as it will quickly turn with high heat, since it is a food processing area I would use linseed / flaxseed oil. It will preserve the wood and can handle some moisture. At my last house I had a large oak butcher block that I used linseed oil on it took a large amount of abuse as that's where I prepared meats for summer sausage and for large brew pots, when the surface got a bit chewed up I used a metal scraper purchased from a local butcher shop that shaved a tiny amount of the surface then recoated, I did try a blend of bees wax and oil 1 time but this created marks with large pots. The best advice I have is to use food grade oil and wipe up excess water don't let it sit the wort is a great food for "stuff" to grow in so a through wipe down after use is a good idea.