Removing old varnish

[Kevin]

A friend of mine is having problems removing old vanish from a cedar sided cottage.
He has been using a sander but the paper plugs up very quickly.
Anyone have any secrets ?
He's tried a pressure washer as well.

[sprucebunny]

Heat gun and a putty knife ???

Cabinet scraper ???

[beenthere]

Does he know what the "old varnish" is? polyurethane, or something of the like? 

[Kevin]

Heat gun might work, I''ll ask if he knows what it is exactly.
Thanks.

[beetle]

Try Purple power, ya know the stuff you buy at auto centers or wall mart. It is a mild caustic solution. Dilute it on the low side, spray it on with a garden sprayer and let sit for 5 - 10, power wash it off.

Absolutly do recommend appling it on a test spot first.

[Kevin]

Ok, I'll mention that.
Thanks, beetle.

[beetle]

Kevin,

When I said "on the low side " dont dilute it to much, somewhere 50/50 or less. I have used it to strip old oil based films on many things, so as long as it is a true varnish and not a Urethane or other high cross-linked polymer, it should work.

[Kevin]

Would this be it?

...  link

[beetle]

Yep that is it, they also have it in gallons which I beleive is concentrated.
Another name brand is called "Super Clean".

I found out the hard way that when you use it concentrated it will remove finishes. I went to clean my deck one day, sprayed it on with the garden sprayer and proceeded to power wash, well it took the finish right off. Wanted to degrease my dozzer so I sprayed this goop on, and again proceeded to power wash, took the second layer of paint off.

I have since used it to strip chairs etc.

But do test spot first.

[Kevin]

OK, sounds good for a go.  thanks again.