Pore filling on 18th century reproductions


I'm fairly new to finishing American 18th century reproductions and am interested in 'best practices' for pore filling woods like walnut and mahogany to match the originals. Not only materials and methods, but also even the level of fill.

My current understanding is that it's best to strive for about 80% fill using shellac only (either levelled with sandpaper as body is built up or padded) as the fill method. I'm also under the impressions that geninue French polishing (with abrasives at the early stages to pore fill) was not used.

What does the SAPFM body of knowledge suggest?
Glass paper was used as an abrasive.
A great book would be a reprint by Dover (0-486-25530-1)  The First American Furniture Finisher's Manual    A Reprint of "The Cabinet- Maker's Guide of 1827 edited by Robert D Mussey, Jr's which has been discussed before and it's fun to read.
You can get modern grain fillers today but many turn white when the color leaves the media when the sun light bleaches it out.
I am not an authority. But I remember a discussion with the Colonial Williamsburg staff where they indicated that locally made brick was ground with a mortar and pestle and then applied as a pore filler with boiled linseed oil as the vehicle. I went over to the brick-making area at C.W.  and picked up some brick shards and indeed they can be ground into an extremely fine powder. However I never tried to fill pores with it. One obvious advantage is it will retain it's color.
Does any one know if the above is factual or a colonial urban legend?

Howard Steier

David Salsibury from the cabinet shop at CW just applies many coats of shellac to fill the pores.  That way you do not have to worry about pore filler color matching.  Commercial pore fillers will also produce a muddy look.  I've been using David's method for many years and I like to way it looks and works.  Yes, it is time consuming but if you want to use mahogany...

Dennis Bork
Antiquity Period Designs, Ltd.
Jeff and Howard,

Thanks for your replies. Jeff as you stated, I'm hesitant to use modern pore fillers because of what happens after the color goes away. How does your shop fill pores on reproduction furniture? I will have a look at the references you give as well.

Howard, I've read about the red brick method and have always associated it with traditional French polishing. Maybe thats a good way to go even today.

Dennis, this is what I was leaning towards as well. Lots of levelling or padding to get the surface flat, but maybe it's worth it. Do you typically strive for 100% planarity or do you just try to get the pores ~80% filled? One other thought I had was to dissolve shellac in butanol (so the solvant evaporates slower) and then sand in the shellac on the first for applications so pores fill quickly with shellac and sawdust slurry. 1 test board done this way looks promising, but maybe I'm missing some long-term problem.

So much to learn.....

When Don Williams lecutured at my local woodworkers club in September, he raved about a product available from TouchupDepot.com called "Gold Dust".  Apparently this is finely ground lemon shellac left over from a printing process. (too fine for the process).  We used some in his workshop, and it was so fine it almost disolved instantly in alcohol.

Don said he has been using it as a pore filler on walnut and mahogany.  He wipes the dry powder on the wood leaving it in the pores, and then mists alcohol over it.  I don't know if he has to do this more than one time before brushing shellacing the whole piece.

I bought a pound of Gold Dust which I plan on using to fill the grain on our oak kitchen table.  Last summer I planed my earlier polyurethane finish off of it and shellaced it. I haven't been happy with the open pores.  Don told me he hadn't tried the Gold Dust on large pore woods like oak, nor had he tried filling the grain on a piece which already had a shellac finish on it.  I plan on trying this on a sample board first.

Tom Meiller

Thanks for the input. I hold Don's advice in the highest regard. I almost gave up on using shellac until I took one of his seminars at Olde Mill about 17 years ago and he turned my world around. I'll be ordering some "Gold Dust" first thing in the morning.

I have heard of the Gold Dust method, but I haven't tried it yet.  I hope it works well.  I got a fromula for a filler from someone who works at the Robert Mussey Studio several years ago and have been using it ever since.  The basic formula is as follows: 1/4 cup boiled linseed oil, 2 heaping tablespoons of diatomite(this is a white powder used with swimming pools and , of course, can be purchased at a swimming pool supplier-a 10 lb. bag will last you the rest of your life),1 1/4 teaspoons of japan drier.  This can be tinted with a Japan Color such as burnt umber(a little goes a long way, and this also tints the color of the piece slightly).  This dosn't give a complete fill by any means, and like any filler, it takes time, but it certainly cuts the number if coats of shellac you will need.  You will have to experiment on scrap pieces with how long to leave it on the piece.  If you take it off too soon ,it will not fill as well as it should. It does take a while to set up. If you leave it on too long , you are in trouble.  When you apply it on areas like carving , just use an old tooth brush to get it out before is sets up too much.  As it has boiled linseed oil for its base, let it dry at least a week before continuing with the finish.  This might seem like a lot of trouble, but it has worked  pretty well  for me.  However, if I find that the  Gold Dust method (or any other) is better, I will switch to it.

                                                For what ever it's worth,

TO Tom M: Regards Golddust shellac and misting alcohol to use as pore filler.  I have tried this method on some  prepared walnut scrap and find it very difficult to to get any build up in the pores. Could some one explain in a little more detail the process.  Many thanks  Blackbird.