Gazette Archive 1/30/03
What is shellac? Shellac is made from the resin of the Lac Beetle larvae, most of which comes from India. It gets it's different color due to the time of the year it is harvested and the amount of refining that the lac went though. Some shellac is dewaxed. This shellac has the wax that is found in shellac reduced to a low level.
Shellac is an excellent choice for a quick drying, non waterproof, finish for wood. It gives wood a wonderful warm natural look that enhances its natural beauty. It can be top coated with almost any waterproof and/or heat resistant finish such as poly or lacquer. With a little practice, one can become quite comfortable using it. When dry, shellac is a safe, non toxic material, that is actually safe for human consumption (let me know how it tastes should you ever try it!). It comes in two basic forms. A liquid premix such as Bullseye, or a dry form known as flakes (or buttons) such as that sold by www.shellac.net
The consistency of shellac is referred to as pound cut. Add three pounds of shellac flakes to a gallon of denatured alcohol, and this is referred to as a 3 pound cut. Most premixed shellac is sold in a 3 pound cut (#3). When you first start using shellac, it is highly suggested that you use a #1 cut. The thinner mix is easier to apply, dries faster, and shellac is easy to repair any mistakes you may make. (I still use #1 cut for everything except for my final coat.) To thin premix shellac, simply add two parts of denatured alcohol to one part shellac. Stir, do not shake.
When mixing flakes, you want to use an air tight jar. I use mason jars for this. Mix only the amount of shellac that you need for a project, as it has a very short (several months) shelf life. To make a pint of shellac, place 2 oz of flakes in the container, add 8 ozs of alcohol, and let it sit for 24-48 hours. Stir every few hours. After all of the flakes have dissolved, you will need to strain the shellac. Use cheese cloth and a wire mesh basket for this task. After straining you can adjust the color by mixing with different color shellac, or, you can tint with dye to obtain the color you want. At this point you want to add the remaining 8 ozs of alcohol.
Shellac can be applied via a brush, sprayed or wiped on. Wiping techniques are a route I have yet to go down, but plan on practicing soon as I want to learn how to do a true French Polish. Brushing should be done with a high quality natural bristle brush. You need to move fast with shellac. Do not over brush, or you will end up with bubbles and/or lines in the finish. Your brush strokes should always go with the grain of the wood. Allow each coat to dry before applying the next coat. Depending on temp and humidity this will run from 1 to 4 hours. Lightly sand each coat with 220 grit paper before applying the next. After sanding, wipe the old coat clean! Use tack cloth if you want. I do not use it because I feel that it leaves a residue that could mess up the finish. If you had any drips or over brushing, go ahead and remove them at this point. Alcohol and 220 paper will remove the mistake very quickly. Redo the area.
After you have applied enough coats to achieve the look you are after, your final coat will need to be buffed out.( NOTE: Skip this step if you plan on top coating with a waterproof coating.) I use #0000 wool and Johnson paste wax. Thin the paste wax with a little mineral spirits until it looks like a thick gravy. Dip the wool in the wax, and then rub with the direction of the grain. You will notice that the wool will glide over the finish as it becomes smooth. When you are done polishing the finish, wipe off the residue. Some suggest that you use a tack cloth for this. I prefer to use a clean soft cotton cloth that has been very lightly dampened with mineral spirits.
You should now wait 24 hours prior to applying a coat of full strength wax to the finish. Let the wax dry to a dull glaze, and then buff out with a soft, clean cotton cloth. You can also use pumice or rotten stone to buff out the shellac. Liberon (www.woodfinishsupply.com or www.liberonsupply.com ) sells felt blocks and liquid rubbing lubricants. Dampen the felt bock, press into the pumice/rotten stone and buff with the grain. Wipe the slurry off and finish with wax. This will give you a satin to high gloss finish.
Another technique is to use liquid soap and a fine grit wet sandpaper. Up until a few months ago I used this technique, but since have changed over to the "wax gravy". Thin the soap with some water. Wet the sandpaper and buff as you would with the other methods. Do a small area at a time, and clean off the slurry often. When you are finished, the shellac will have a hazy or cloudy look to it. Not to worry, as the wax will buff it right on out.
If you plan on using a top coat such as poly, lacquer or varnish, you need to ensure that your final coat of shellac is a dewaxed shellac. Using a super blonde will insure that your look hasn't been changed. Lightly sand, and then apply your top coat. When I do top coat, I use a wipe on poly. Two to three light coats normally do it. You are only protecting the shellac from water damage, not using the top coat as your finish per se. I suggest that you wait several days for the shellac to fully 'cure' prior to top coating though.
Should you need to repair the finish, sand out the damaged are. Apply shellac as you would if the area was new, until you match the original finish. If you need to remove shellac, use 400 grit sandpaper that has been dipped in alcohol. This will remove the finish quickly.
Here are some of the different
types of shellac:
While this is not intended to be inclusive of anywhere near all the information out there about shellac, I trust it will help some of you who have not used shellac to give it a try. I have only touched the tip of the iceberg on shellac. There are some real experts out there who can expand upon this article far better that I can. For some really good advice on the use of shellac, read up on the technics of Ian Hosker, Michael Dresdner and Jeff Jewitt.
Hope this helps someone!