Top coat for outdoor stain??

Nov 09, 2007 9 Replies

I made a gothic bench from douglas fir and stained it. Assembly will be made with wedged through tenons and tusked through tenons. I want to use it outside on our deck and realize from other projects that polyurethane doesn't quite hold up like I would want it to. Would shellac give a lasting protection on stained fir? I was thinking of a good quality car wax. At least that would not peel and I could apply as needed. Or, has anyone used something on the order of Thompson's waterseal on outdoor furniture??



Barry


I don't know of any film-forming finish that stands up to sunlight. The failure mode is peeling and flaking that allows the wood underneath to weather in patches. Not a pretty sight. I'd use a penetrating oil finish like Boiled Linseed Oil (BLO) or Tung Oil. You'll have to reapply occasionally depending on exposure, but it shouldn't require much surface prep. Beware that many finishes that claim to be Tung Oil, like Formby's or Minwax, are really varnishes with a little Tung Oil added to emphasize the grain. These will fail outdoors just like varnish.

DonkeyHody "In theory, threory and practice are the same, but in practice they are not."

I've had both good and bad results with poly so I'd not use it in most cases, especially direct sun.

Best results I've had is with Penofin Oil. UV protection, no film, quick and easy to apply.

There is nothing - NOTHING - you can put on it that won't require maintenance. Worst are film finishes (varnish, poly or alkyd; lacquer; shellac); easiest to renew are oils. Wax? Dunno, probably about as good as anything.

reapplied every year or two.

I was thinking Spar Varnish, the stuff they made for boats that is now used on exterior doors but then someone mentioned Penofin. Yup, that's what the pros would use. Penofin can come in colors too but just get the straight stuff. Any good pro paint sho[p should likely have it.

3 COATS LAMINATING EPOXY FOLLOWED BY 3 COATS VARNISH/POLY CONTAINING UV INHIBITORS.

(Cap Lock off)

The epoxy protects the wood and the varnish protects the epoxy

THe varnish/poly is simple to repair.

Lew

.

Lew, Only 3 coats of Varnish ?

All kidding aside - you did forget to mention it should be 'short oil' varnish.

DO NOT, repeat NOT use 'Spar Varnish'. If you do, on a warm summer day you WILL glue your butt to the bench !!

'Spar' NEVER hardens . . . it's not supposed to. The idea was to protect wooden spars, allow movement & flexing, and yet be 'clear' to allow inspection of the mast, yards, etc.

Regards, R>

If this group was composed of boat builders, would have suggested 8-9 coats of both epoxy and varnish/poly..

Lew

Fri, Nov 9, 2007, 8:27am snipped-for-privacy@ptd.net (Barry=A0Kwasny) doth queryeth: =A0Or, has anyone used something on the order of Thompson's waterseal on outdoor furniture??

There's better than Thompson's. Talked to the Franklin glue guys awhile back, I was told some sculpturerers use Titebond II as a coat for outdoor sculptures. Apparently they're holding up well. I've not tried outdoors, but it seems to be working quite well on some of my indoor projects.

JOAT Viet Nam. Divorce. Cancer. Been there, done that, got over it. Now where the Hell are my T-shirts?

- JOAT

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required