TL;DR: Cork seems to require a surprising amount of polyurethane to cover/seal its surface. Like a lot.
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So it’s not often I am surprised when I am working on a laser project…
I have finished cork in the past with a cork sealant, but I use it rarely and the entire container solidified into something waxy. So I googled, and it looks like polyurethane can seal cork too. Great, I have that.
So I pour some poly out and start to apply it … and apply it … and apply it, and it is just sucked right into the cork, all gone. In the end it took at least 3x as much polyurethane to get coverage compared to a similar area of hardwoods. I’ll report back once it dries, but it was strange enough that I thought I’d mention it.
Yeah I am wondering if it just worked into the spaces between the bits of cork, and I’ve made a solid brick of poly. We’ll see once it dries, but if it’s much more rigid than before I guess it’ll support that theory.
That is what happens. Try it on Bamboo and you’ll see it’s not soaked up like that.
Instead of pouring on, I just apply light coats with a cheap painters brush. It covers the surface fine, but you have to brush it dry first to get rid of a lot of the ash.
Ah right no I pour it onto a small tray and then dab and wipe with a lint free rag. I find it’s best to work in smaller sections with wipe on , you have to wipe the excess off almost immediately to get a really consistent finish.