by 48Rob » Mon Nov 03, 2014 6:17 am
I use oil based poly over oil based stain all the time.
It has been done for years.
You can put oil, or water based finish over oil stain.
What you don't want to do is put oil over water based.
Oil dries hard and does not stretch.
Water based/latex stretches/moves, hard non stretch oil over soft stretchy latex will fail.
As to your question about "should I protect it" yes, it would be a good idea as stain does not seal the wood from moisture damage.
Rob
PS. You need to get a new paint store guy that has a clue.
Paint stores sell products that are designed to seal and protect multiple surfaces, inside and out.
If he can't answer that simple question, he isn't to be trusted to give advice on what kind of paint his customers need.
Waiting for "someday" will leave you on your deathbed wondering why you didn't just rearrange your priorities and enjoy the time you had, instead of waiting for a "better" time to come along...