Decks, Patios, Porches and Docks - Stripping polyurethane off of deck

The previous owner of my house used polyurethane on the decks.(3 of them).It is worn of the highly travelled spots but is still on the sides and railings.I have tried powerwashing,deckwash,bleach and nothing will touch it.Not even direct spray from a 1200 PSI powerwasher. I tried a furniture type Poly stripper and it works but will take forever.It takes a lot of scraping and scrubbing and would take a lot of material to do three decks.One thing that works good is my sandblaster but is messy and dusty.I was thinking of renting a wet sandblaster.Basically a powerwasher with sand mixed in with the water.Obviously this could do some damage but if i am careful and keep the pressure back would this work ok?By the way its pressure treated lumber and is well aged.

ochrisl,
Oh My Gosh!
The person that polyed three outdoor decks should be arrested, tried, and hung by their 'bristles'!
Not even marine spar varnish will hold up very long outdoors.

You're right, the deck washes or bleaches won't touch it. You need to go to a specialty paint store, tell them your problem, and get a strong deck stripper. It will contain sodium hydroxide(lye) and some other additives. Please read the precautions carefully. Wear eye protection and cover any greenery around your deck.
This stripper and yor PW should do a pretty good job on your problem.

good luck,
fred

Thanks.It is marine type varnish,looks like its for boat decks by reading the can.

I couldn't resist adding this:

Now you know why the owners of wooden boats are always working on their boats - been there, done that...

fred

PEEL AWAY 7 which is a safe remover will do your job keeping the natural color of the wood. This product is also marketed under tyhe PEEL AWAY Marine safety Strip label for use on boats.