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Dick Bringhurst
12-16-2007, 10:36 AM
If I understand correctly, shellac (Zinsser Bulls Eye) can be used as a primer under Oil Base of Water base paints. Am I correct? Dick B.

Jason Roehl
12-16-2007, 11:24 AM
In a word, yes. Pigmented (or non, as long as it is dewaxed) shellac is considered a "universal primer". There are always exceptions, but when it comes to most types of painting a homeowner/Joe DIY will do, shellac goes over just about anything, and goes under just about anything. One slight drawback is that it is not particularly brush- or roller-friendly, lending itself better to spraying. As a painter, only in the case of major fire or water damage, do I use it in a widespread manner, otherwise, I generally just use it in the rattle cans for spot-priming stains--mold/mildew stains after cleaning, roof-leak stains, pen and marker marks on walls, etc. If you need to prime large areas due to smoke or water damage and are not set up for airless spraying (and all the necessary precautions for airborne alcohol fumes), then there are better products available. Check with your local dedicated paint store with your particulars to get their best recommendation.

Howard Acheson
12-16-2007, 11:27 AM
Only dewaxed shellac can be used under oil based poly varnish or waterborne acrylic finishes. The only Zinsser product that is dewaxed shellac is their SealCoat (www.zinsser.com/product_detail.asp?ProductID=72).

Their other shellacs are not dewaxed and can not be used under oil based poly or waterbornes.