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View Full Version : Poly on top of Shellac?



John Miliunas
10-04-2004, 5:34 PM
OK guys, here's the scenario: Spent a LOT of time this weekend milling, dimensioning and cutting down a bunch of Maple to be used for interior casings around stationary windows we need to replace. LOML likes the softer look of shellac on the Maple. Me too, quite frankly. BUT, windows being what they are, get cleaned periodically and it's usually with some mixture involving amonia. Amonia doesn't play nice with shellac. So, I was thinking about putting on a coat of shellace to seal the wood and give it the softer appearance and use water-based poly for the second coat. Any reason these two shouldn't play nice together? :cool:

Jim Becker
10-04-2004, 5:48 PM
As long as you used de-waxed shellac...no problem. But polyurethane varnish will not stick over waxed shellac. You might also consider the other two harder varnishes, (alkyd and phenolic) in lieu of poly. They are often more clear, too, although not usually available in water bourne. Waterlox, Sherwin Williams Fast Dry Varnish and Pratt & Lambert #38 are examples. The latter is soya oil based and will also go on with a lot less yellow/darkening effect.

John Miliunas
10-04-2004, 5:51 PM
Jim, you ROCK, dude! :D Just the info I was looking for! You've made LOML a happy lady and I can work on getting all that millwork outta' my shop sooner! :) Many thanks! I'm heading to the shop right NOW! :cool:

Jim Becker
10-04-2004, 6:05 PM
One other thing, John...if this is for the maple stuff and you want to keep the color at least close to natural...you're going to want super blond shellac. If you were spraying, I'd suggest you also consider the new (believe it or not) water bourne shellac products that Target Coatings came out with. I just ordered some super blond and garnet to try out on the armoire project. (garnet for the casework after it's dyed and super blond for the two drawers and pine T&G back)

Roger Barga
10-04-2004, 6:28 PM
Have you considered using Benite to seal the wood? I refinished a maple dresser for the LOML and she wanted to retain the natural white color - I applied Danish Oil, Shellac (super blonde) and Benite to different samples and the benite was the lightest, in terms of the least change in the color of the maple. I've read that Benite is used in the boat building trade to seal wood, so it should provide a reasonable protective layer (see article below). Just a thought - I'd be interested in hearing from others familiar with this product.

Roger

Link to article on interior refinishing from Bellingham Boat Tips:
http://www.byc.org/Boating%20Tips/byc%20boating%20tips/tips974.html

Chris Padilla
10-04-2004, 8:00 PM
John,

I'm pretty sure you have Velvit Oil. I think it might work nicely for the maple but it tends to yellow it up as you probably know.

Jason Roehl
10-04-2004, 8:34 PM
John, I'd probably go with some sort of spar varnish on those windows. I've been in so many houses where the trim looked great after 5, 10, 20, 30 years, but the windows looked like crap because the poly just doesn't hold up to the sun and condensation that windows get. One option for a totally clear topcoat over the shellac would be water-borne exterior polyurethane. I can't for the life of me remember the brand name right now, but I have used it before on the exterior of stained fiberglass doors (it doesn't pull stain when brushing like an oil poly would). It is a little on the salty side, though--I think I paid about $17 per QUART locally, but at least it goes quite a ways (it's very thin). Hope that helps, John.

Jerry Olexa
10-04-2004, 8:42 PM
I love shellac also, Bret ! Make sure its DeWaxed and any varnish or topcoat can then go over it! Regular shellac and Poly for one do not mix. I also agree you need more protection over the shellac in this case for those heavy use areas (windows).

John Miliunas
10-04-2004, 9:18 PM
Thanks for all the additional info and tips, gentlemen! :) (I think you guys would give Jeff J. a run for his money!) Anyhow, this is kind of a "rush" job to begin with. I've got the windows coming Friday and a helper on Saturday! :D Then, LOML popped the good old, "Hey, why don't you put the finish on them *before* you nail them up?!" Yeah, yeah....Makes sense. Dagnabit, I just HATE it when she's right! :eek: :mad:

I got the shellac on this evening and I'll probably do a light hit with the ROS tomorrow, wipe them down and start with the poly. Yes, I'm going with poly. It's the Tripp-Carver flavor, water-based. This way, she'll have the slightly "softer" tone of the wood and I should get the protection I'm looking for. I've used this stuff before and it does a pretty fair job. As for condensation, I sure as heck hope there will NOT be any! That's part of the reason for getting these replacements; Old ones are junk. New ones are the Low-E, tinted, super-duper, turbo-charged variety! :D They'd BETTER not even entertain the thought of allowing any condensation! :) Thanks again, guys...I'll let you know how it all turns out! :cool:

Bob Smalser
10-04-2004, 9:21 PM
Ditto Jason's spar varnish...a serious one like Epiphanes...perhaps over Benite sealer for the clearest possible finish or Deks Olje, Watco or hot linseed-turps for a warm finish..

At least use a marine-grade poly with serious UV inhibitors...

...then you wan't have to redo it for a long, long time.