Shellac as a sealer/filler under latex paints?

[David]

I am refinishing a dresser and I have painstakingly stripped old paint, cleaned with mineral spirits to not raise the grain and then sanded with 60,

150 and then 220 grit. So now that I have used a latex sealer and two coats of latex paint I have noticed that the grain is raised after the paint has been applied.

I am thinking that since water raises grain and the paint I used is water-based. So the paint raised the grain?

If this is true, what is recommended to prevent this? After sanding, should I put a coat of shellac or something like that and then prime and paint over that? Any advice would be appreciated!

[Leon]

Most likely

You can apply the Shellac or you can lightly wet the freshly sanded surface so that the grain will raise, "lightly" sand to remove the raised grain and then apply your water based product.

[B a r r y]

Dewaxed shellac, like Seal Coat, works great under latex. BIN is white pigmented dewaxed shellac, and works even better under some colors and for exterior work.

Barry

[David]

Dewaxed shellac is a good barrier to any remaining chemical stripper residue. Zinnser's "Seal Coat" would be a good choice. Check the bottom of the can for the date. It doesn't last forever. I try to buy mine no older than 6 months.

David

David wrote:

[GerryG]

[bridger]

sand the primer

[GerryG]

[Norman D. Crow]

Yup, ANY primer, if you want a nice finish. Just taught my daughter about that on some S4S 1 x 12 pine she was going to use for new baseboards. She put on a coat of Orange shellac, then next day I hit a spot with some 320 just lightly by hand,enough to knock the "fuzz" off, then it was nice 'n' smooth like a baby's butt. She decided to sand the rest, then about three more coats shellac, they look real nice against the light color woodgrain panelling.

[Tvaughan1234]

I tried shellac sanding sealer under latex and found the latex looked ok but chipped or rubbed off easily. The surface was so smooth that adhesion was poor. Shellac over latex on the other hand is fine.

Terry

[nospambob]

[drgrafix]

[Tvaughan1234]

Not fresh, it was an old bottle of commercial mix. It seemed to harden OK. Don't know if it was dewaxed, I'm no expert on shellac. I wanted a smooth surface under the paint, and got it, but had to try something else. Would dewaxed stuff be better? How can you tell if it is?

Terry

[GerryG]

Norman, agreed. Especially if you were building the shellac up to a surface film (then definitely!). However, that thickness is not really needed for sealing. Typically using a 1/2# cut apply one coat, scuff sand surface to remove broken fibers now locked in place, then a 2nd coat to complete the sealing (dewaxed shellac, of course). At this point you could lightly sand, but the resulting surface is probably still pretty rough as there's little surface film built up.

The same formula also works under most water base clear finishes to prevent grain raising, and a 1/2# cut of shellac will dry very-very fast. An additional benefit in that case is the shellac will cover any trace amounts of resin or oil that might give the wb finish some trouble.

GerryG

[David]

Use dewaxed shellac whenever you are gonna overcoat it. Shellac with wax in it should be used only by itself. The wax will reduce water resistance and also interfere with adhesion of topcoats.

David

Tvaughan1234 wrote:

[nospambob]

Canned premixed is usually waxy except for Zinssers Seal Coat which is dewaxed. Spray shellac is dewaxed. Fresh mixed shellac has typically

6 m>>Was the shellac fresh dewaxed?