"Curing" Shellac sealer coat?

[Tom B]

I've searched a bit and read a lot (Jewitt, etc.) but can't find a direct answer to the following question:

If I use a 1# cut of dewaxed shellac padded on as a seal coat (over a stain or even raw wood) is there some rule of thumb about how long it should dry before I overcoat it with an oil based finish (varnish, BLO, etc.)?

It's always seemed to me that once shellac is dry to the touch (maybe

15 - 30 minutes with a 1# cut), it's done its thing, but I see and hear references to "curing" it before overcoating, hence the question.

Regards.

Tom

[nailshooter41]

SNIP

You can recoat with shellac in as little as 20 - 30 minutes depending on the environment in which you are working.

I wouldn't put a final coat of finish on until the last coat was on for a couple of hours.

Robert

[B A R R Y]

It also matters what is going over it.

I let Seal Coat dry overnight under water base. For other stuff, I just make sure it's not sticky any more.

---------------------------------------------

** **

---------------------------------------------

[Nova]

Shellac doesn't actually need to cure as it's an evaporative finish. What can happen is that when several coats are applied too quickly the outer coat can seal the pervious layers slowing the drying process. This will cause a soft finish until given enough time for the underlying coats to "cure" (dry).

[Edwin Pawlowski]

Finishes dry to the touch in a short time, but full hardness can take day, even weeks for polyurethane to reach maximum hardness. Shellac is dried as the alcohol evaporates, but I'd still give it a few hours or even overnight before putting another material on top. But that would be my practice with no scientific research to back it up.

[Lew Hodgett]

I know diddly-doo about finishes, but why rush it?

When I use shellac, allow it to cure at least a week before taking next step.

YMMV.

Lew

[RF]

You are right in your information, a !# cut is very thin and 30 minutes would be fine for a drying time.