micky wrote

My house was built when formica counters were't rolled at
corners but there were saparate pieces on tops and sides.

Mine too.

The bathroom counter got wet and I didn't dry it for 10 or 15 minuters
and even then I might not have done a perfect job, and it swelled.

Never got that result with my kitchen bench.

But only a little, and it seems to have gone back**
so close to the original size I can barely notice.

I need to waterproof the corner edge.

What should I use????

I painted the exposed not laminated particle board ends with estapol.

They arent laminated because they arent visible with the counter installed.

**Unlike my kitchen counter. I had a plastic bottle of distilled water
on the cement basement floor for months, without its leaking at all.

When my friend who only drinks distilled water was about to
arrive, I put the bottle on the kitchen counter and the next
morning the counter had a puddle on it and the particle board
inside had started to swell. It got worse in the next day, both
vertically and horizontally, and never shrank again, afaict not at all.

That had to be replaced, but the bathroom counter,
well, maybe I could tell if I looked at, but I'd rather
not look and imagine that it's perfect again. :-)