I don't see a need. Mixed fresh from flake and high quality denatured
alcohol, it should set up hard and tack free in about 10 minutes.
(Milliseconds, if you forget to wipe the jar's threads before screwing on
the lid.) It's fully cured when the alcohol evaporates, about an hour at
most for freshly made. Even when using store-bought, toss it if it doesn't
set up hard in 24 hours. Shelf life of shellac is relatively short. Alcohol
is hydrophilic, and soaks in moisture from the air. The moisture interferes
with curing, and can cause the film to dry cloudy. Keep it tightly capped,
and plan to use it up quickly. I mix 3 lb batches, and pour out just what
I'll use that day, and cut it with fresh alcohol. A quart size round
Tupperware is the right size for me. 1.5 lb cut works pretty well for
brushing. 2 lb cut or very slightly thicker when padding.
Douglas - careful here. The Zinseer 3# cut if for finishing.
Although I have not actually had any tragedies using this for a
sealer, it is best to get the yellow can of Zinseer marked "sanding
sealer". This is the correct viscosity and "cut" for your
application. Also, it is dewaxed shellac, as opposed to the 3# cut
(that isn't) which helps ensure adhesion.
You can actually sand and recoat when the shellac will easily sand
giving off only a fine white powder. This really depends on your
application method as well as your weather conditions. If you spray,
your coats will probably dry quite fast and you can sand in a
relatively short time.
When I spray shellac sealer, I can easily sand within 45 minutes on a
warm, clear day. Even though the finish powders up nicely under the
paper before then, it is still soft enough to leave unnecessary tiny
scratches. If I can, I wait an hour or so just to be sure I have the
hardness I want.
When it is cool, humid/drizzly, and I have to brush or pad, I usually
wait at least a couple of hours before sanding.
If I brush the shellac, I put a lot more on as it is harder to handle
than just whistling by with a gun. So in bad conditions and a brush
But remember, the more coats on the surface and the thicker finish you
apply from multiple coats means more drying time between sanding/
You cannot screw up by waiting for shellac or lacquer to dry
properly. You can screw up by getting on with your processes too
early. Take your time - good finishing requires patience.
If you go with the lacquer as a final finish, there is no need to sand
between coats. I NEVER do unless I have screwed something up. If you
sand between the coats you will leave debris on your project surface,
and in nooks and crannies where you cannot get it all out. This
sanding dust and bits off your paper will however find a way to be
prominently displayed in your final finish coat.
With resolvating finishes, sanding between coats simply isn't
necessary unless you are removing a run, bad brush stroke, or getting
out some dust nibs.
Again - many thanks for the valuable advice.
Purchased the SealCoat product and applied the first coat.
We had unusually low humidity (for Houston at least) and temps in the low 70's
and as Mark and Larry commented, the first pass was very tacky before finishing
pass - may not be the best choice of words - the piece is approx. 8" wide and
which is in the direction of the grain - so a pass covered about half the width.
Two obviously neophyte questions:
1. Presume that after applying the product it should be worked into the surface
and the excess is rubbed off. Is this correct?
2. There are several small patches that have a faint whitish appearance - and
surface is smooth to the touch.
Per Robert's recommendation - do not plan to sand and will apply two coats of
Are these white patches normal? Will they disappear once the lacquer top coat
Thanks again everyone!
Work FAST! Shellac dries quickly. Don't tip it off, as you would with
The whitish patches may be "blushing", which is embedded moisture. The
second coat of Seal Coat should eliminate it. Was there water in brush?
Get the blush out before applying the lacquer. Don't move to another
step until you've got the current step right.
Applied the SealCoat with a dry cloth and the humidity was uncommonly dry - at
When applying - should I leave the material on the surface or try to rub in /
Wipe on & STOP! <G>
If you keep rubbing, you'll just make a sticky mess.
There isn't much else the white can be other than moisture or debris.
Did you sweat on it? No, I'm not kidding... Drops of sweat blush
lacquer and shellac.
Thanks for your reply.
OK - no rubbing in or buffing after application.
No sweat fell on the work piece - although were it anytime other than the few
cool, low humidity weather we get here that may have been a possibility.
After the application, wiping down, and replacing the lid on the can -
apparently some of
the coating dripped onto the work piece - this is where the whitish areas are,
to a small area where the grain is very open.
After sitting for several hours, I buffed the entire surface and the white has
Temps are good and the humidity is down right now - so will apply the second
coat - with
Regards and best wishes for a prosperous New Year!
The second coat of sealer is done and overall appearance is very nice, IMO.
Have now noticed the presence of some very fine scratches and a slight
the shellac coat - not a run, but a noticeably slight difference in thickness.
Will the lacquer (planning on 3 coats) either melt into the sealer or build up
these indications will not show?
Certainly understand that without putting eyes on this replies are based solely
I am thinking the lacquer may melt into the sealer and provide sufficient film
provide a suitably smooth surface finish.
Want to do the best I can, without being too overly meticulous about minute
Thanks to all again for the expert guidance - best wishes to all for a healthy,
prosperous New Year!
The lacquer won't "melt" the sealer - they have different solvents.
The uneveness in the sealer coat will telegraph through the lacquer.
If you don't need to sand, don't, but if you have to sand, you sand -
just wait a suitable amount of time.
You could use Flickr!, or approved equal, to host some of your
pictures. It would make it easier in future to discuss what you're
On Wed, 31 Dec 2008 16:54:50 -0600, Douglas R. Hortvet, Jr. wrote:
That could be the result of brushing. I've never had good luck brushing
shellac. Any overlap will show up as you describe.
I've had better luck using some of my wife's makeup remover pads wrapped
in a piece of old T-shirt. I apply a lot of very thin coats.
Thanks for the reply.
I applied the sealer with a section of wadded up old t-shirt, folded to provide
face to the work piece.
Rather suspect the indication is the result of an uneven edge of sealer.
Guess I will have to sand - as another poster (RicodJour) pointed out that the
won't "melt" the sealer, and I sure do not want that discontinuity propagated to
finish coat of lacquer.
I'm no genius when it comes to working with finishes, but the
following work for me:
1) Patience is a virtue.
2) Finish materials are temperature dependant.
If you can't guarantee 70F minimum for at least 3-4 hours (2 before, 2
after applying finish), find something else to do that day.
In dry climates, finishes that dry relatively slowly in other climates,
dry quite fast. Higher humidity conditions slow down curing.
In Tucson, I can't follow the directions as far as time between coats or
especially time to wipe off excess finish. If I wait the full instructed
time, the finish becomes so tacky that the wiping rag is pulled apart into
If you're going to be dumb, you better be tough
On Sun, 28 Dec 2008 23:52:14 -0600, Douglas R. Hortvet, Jr. wrote:
Doug, that sounds like the stuff with wax in it. OK by itself, but not
good if you're going to put anything else on top of it. Also not as
What you probably should have gotten was Zinsser's SealCoat. It's sold
as a sanding sealer, but it's a 2 pound cut of dewaxed shellac.
If you have the patience, you can let what you have sit for a week or two
and the wax will settle to the bottom and you can carefully pour off
about a half can of dewaxed. Then thin as desired.
Shellac will dry to the touch almost instantly for the first few thin
coats and I've never had to wait more than an hour to recoat unless the
weather is very cold and damp.
But that doesn't mean it's cured. If you try to sand it (lightly! or
you'll melt it!) without waiting at least a week you'll get little gummy
balls of shellac all over your sandpaper.
A very experienced woodworking friend of mine claims that shellac never
quits getting harder. My experience with old furniture seems to support
some years ago I made a simple footstool of red oak, and to fill the
grgain I used Behlen's Pore-O-Pac (and the solvent to adjust the
consistency). I got the idea from someone here ...
That sure did that job, but it also made the wood much lighter in color.
I probably should have adjusted the pigment somehow, but wasn't
experienced in doing things like that (still am inexperienced). After
that, shellac and polyurethane. That has been quite durable over the
just about 8 years in use. Photo's on abpw.
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