PADDING SHELLAC

By Jeff Jewitt

French Polishing quickly spread to America but with some variations. Information on theearly technique is scant, but a finishing book published in 1827 describes the generaltechnique. The process omitted the pumice or plaster steps to fill the pores. Instead, asize of dilute animal hide glue was brushed on open-grained woods like walnut and thensmoothed with glasspaper (the equivalent of our modern sandpaper) when dry. Then a linenrag with a flannel core was used to apply the shellac in circular motions over the entirepiece of wood. This was repeated several times until a suitable finish was obtained. *Source - The First American Furniture Finisher's Manual- A Reprint of "TheCabinet-Maker's Guide" of 1827. ed. 1987 Robert D. Mussey, Jr. Dover Pub, New York.

There is no question that shellac remained a favored furniture finish in America fromthe early 1800's up to its displacement by cellulose-nitrate based lacquers at the end ofWorld War II. While brushing and spraying shellac became the favored applications, themethod of "padding" shellac with a cloth has continued to the present day as aeasy and practical way to apply shellac. In this article I'll demonstrate the basics ofhow I pad shellac in my cabinet-making and restoration business.

Padding shellac is a low-tech process that is perfectly suited to the professional andamateur finisher. The advantages that it offers are numerous. First, the process usesshellac, a non-toxic, FDA approved natural resin. The carrier for shellac, ethanol, isrelatively non-toxic (ethanol is the alcohol in liquor) and the fumes are not unpleasant .Secondly, shellac dries fast, so dust does not pose a great problem and shellac finishescan be done rather quickly, usually in several days. Third, it is a much easier techniqueto master than French Polishing. Lastly, shellac is a good-looking, durable finish thatcan be easily repaired if damaged.

The materials for padding shellac are inexpensive and easy to obtain through mostfinishing companies. (See Sources). They consist of shellac, denatured ethanol, paddingcloth, and a drying oil such as boiled linseed oil or tung oil.

THE MATERIALS

-- I prefer to make my own shellac solution from dry shellac flakes. Usingfresh shellac avoids one of the classic complaints against shellac as a finish - it won'tdry. Shellac is comprised of organic acids which react with alcohol in a chemical reactioncalled esterification. This gradual reaction produces esters which are gummy substancesthat inhibit the drying of the shellac. Although it's possible to use pre-mixed shellac,any liquid shellac older than 6 months should be tested for possible drying problems. Todo this, place a drop or two of the shellac on a piece of glass. If it's not dry to thetouch in 5 minutes, don't use it. You can use pre-mixed shellac but this is only availablein orange or white (chemically bleached). There are a wide variety of grades to buy in dryform (see sidebar -- shellac) and if you make the shellac solution yourself, you areguaranteed a fresh solution.

Alcohol

-- There are four suitable alcohol solvents for shellac - methanol,ethanol, propanol and butanol. Methanol is an excellent solvent, but it is toxic, so Iavoid using it my shop. Ethanol is far better because of its low toxicity. Butanol has anodor which I find disagreeable so I don't use it as the main solvent. Propanol, thealcohol in rubbing alcohol can be hard to get in chemically pure form but it’s a goodsolvent for adding to shellac solutions as a retarder.

Padding Cloth

-- The best cloth for applying shellac is sold as padding, trace, orFrench polishing cloth. The best cloth should be clean, lint-free and absorbent. The bestproduct I have used comes in 12" squares and has a rumpled texture similar tosurgical gauze.

Oil

- Use either linseed oil or tung oil as both a sealer coat and to give greaterdepth to the finish. A very small amount is used and I have not been able to discern adifference between the two under the shellac finish. Always use boiled linseed oil.

PREPARATION

No finish can hide sloppy surface preparation. On new wood, I plane, scrape and sand to180 or 220 grit on critical surfaces like tops and sides. I also do as much surfacepreparation that I can on the project before it's glued up. I generally tape off tenonsand other joints so that oiling from the next step doesn't contaminate the wood. Onnon-critical surfaces I leave the wood right off the plane. If the wood is to be colored Iuse water-soluble dye type stains and since these raise the grain, I knock down the raisedfibers with maroon synthetic steel wool after the dye dries. I prefer synthetic steel woolbecause it won't cut through the dye on the edges. After the wood is smoothed down you'reready for the first step.

OILING

The purpose of this step is to seal the wood and give it greater depth. On re-finishedpieces you can omit this step. Oils will accentuate the figure and deepen the color,particularly on curly maple and cherry. I have used a variety of oils, but I like linseedand tung oil the best. The amount of oil that is used should be very little. Perhaps athimbleful per square foot is all that's needed. Apply just enough to deepen the surfaceof the wood.. Do not flood the surface with oil. Apply the oil with a clean soft cloth,rub the surface briskly and it will penetrate quickly. After several minutes, beginapplying the shellac.

PADDING SHELLAC

Make a pad from the padding cloth by folding it to the shape as shown in the photo.There should be no creases or seams on the pad bottom. Pour approximately 1 ounce ofalcohol into the pad and work the alcohol into the pad. Then pour about 1/4 - 1/2 ounce ofa 2 lb. cut shellac into the bottom of the pad. I like to keep my shellac in round squeezetype bottles. This simplifies dispensing into the pad.

Starting at the top of the board, bring the pad down lightly and drag it across thetop, right off the opposite edge. Come in from the other side and repeat the stroke.Continue down the board in alternating stripes, with the grain of the wood. When you'vereached the bottom, start again at the top - it will be dry enough for you to repeat thesame sequence. Keep doing this until the pad is dry, then recharge the pad with moreshellac. On tops, do the edges first after recharging the pad, then continue the samesequence as above. If there is a complex molded edge, conform the pad to the shape of themolding. Give the other parts of the piece a padding coat of shellac - aprons, legs, andsides. When the board is tacky and the pad starts to stick, stop and store the pad in ajar with a screw type lid.

After the first application of shellac it should be dry enough to scuff sand inapproximately 1 hour. Using 320 grit stearated sandpaper (aluminum oxide mixed with zincstearate as a lubricant), lightly scuff sand the surface of the shellac. Scuff sanding isa term for lightly sanding a surface - applying just enough pressure to scuff the surface.After this, smooth out the surface with maroon synthetic steel wool. Then apply shellac inthe same manner as above to the other sides of all surfaces, undersides of tops, insidesof carcasses, etc. When this is dry after an hour, scuff sand and wool these surfaces likeabove. Then glue the project together. Be careful to avoid excess glue and make sure thatclamps are properly protected. If any glue squeezes out, you can pull it off like scotchtape after 30 minutes to an hour. Don't let it dry completely, it may pull off finish whenyou try to remove it.

The sequence is then repeated - starting at the top of the board and working your waydown. The pad should glide easily over the surface and you should have an even coat ofshellac on the surface. As the pad starts to dry out, you can switch from a stripe patternto polishing in a circular pattern or a series of figure eight’s to get even coverageon the board. Replenish the pad with more shellac, (a good squirt from the squeezebottle), and stripe the shellac on the board. Stop when the finish is tacky and the padsticks. At this point, the surface should have an even shine, indicating a surface buildof shellac. Put the pad back in the jar and let the finish dry overnight.

The next day, examine the finish. You should have an even coating of finish on thesurface. If you are working with open-pored woods like walnut or mahogany, you'll seecrisp outlines to the open pores. This level of finishing is appealing to some and you canstop applying shellac - simply skip to the rubbing out stage at the end and you're done.For surfaces that will receive a lot of wear and tear you may want to apply several moreapplications for maximum protection. Either way, the choice of whether or not to build upmore finish is up to you.

If you want to apply more shellac, repeat the scuff sanding and wooling sequence asabove and apply more shellac. Start with striping the board and then switch to circles asthe pad dries out. Recharge the pad at least 3 or 4 times, and when the surface is tacky,stop. This step should take about 10-15 minutes on a 24" square surface. Let thepiece dry overnight.

The piece is then smoothed with 320 grit stearated sandpaper, steel-wooled and then theshellac re-applied as before. Repeat this procedure until you've built the finish up tothe film thickness that you want. You don't gain any added protection after 4 or 5applications - only the aesthetic difference that thicker finishes bring. If you want,repeated applications of shellac with 320 grit sanding in between is a method that can beused to completely fill the pores in woods like mahogany and walnut. If the finish isthick enough, the surface can be leveled completely smooth, removing the outline of thepores.

After the final padding application, let the project dry for several days beforeproceeding to the rubbing out step below.

RUBBING OUT

Rubbing out the shellac finish results in a smoother, better looking surface quality tothe finish. The beauty of the padding application is that there are no brush marks orother surface irregularities to level, so this step usually goes very quickly. The firststep is to take some 400 grit wet-dry silicon carbide finishing paper and level thesurface of the finish. Then, using 0000 steel wool, squirt mineral spirits onto the pad,and then dip the pad into a can of paste wax. Working with the grain, I bear down fairlyhard with the steel wool and rub the wax on the surface. I wait until it begins to haze,then I wipe off the excess and buff to a satiny sheen. If a higher gloss is desired, youcould rub the surface with rottenstone mixed with mineral spirits before waxing.

MAINTENANCE

If the piece is not subjected to a lot of wear and tear, a yearly re-waxing keeps itlooking great. For tables, chairs and other high wear items, you can rejuvenate the finishby removing the wax with mineral spirits, then dry-wooling with maroon synthetic steelwool (000 equivalent). Then apply a light coat of shellac, let dry and re-wax.

SHELLAC, WHAT IT IS, WHERE IT COMES FROM, AND HOW TO USE IT.

Shellac is derived from a natural resin secreted by a tiny insect called LacciferaLacca. This insect, about the size of an apple seed, alights on certain treesindigenous to India and Thailand and feeds off sap in the twigs of the trees. The insectssecrete a cocoon type "shell", which is harvested by workers shaking the treebranches. In this form the resin is called sticklac and contains bits of twig, insect andother contaminants. The word "lac" comes from the Sanskrit lakh - which meansone-hundred thousand.

The sticklac is then washed to remove impurities and a red coloring matter. At thispoint it may be either refined by hand or machine. Buttonlac is processed in India and isan impure form of shellac. It is reddish-brown in color and is sold in 1"-2"wide buttons, usually with the name of the dealer stamped on one side. Seedlac is anotherimpure form and is processed further in India to better quality lacs, or exported to othercountries for further refining. White shellac is made in this country by the Wm. ZinsserCompany from imported seedlac which is dewaxed and then bleached by bubbling chlorine gasthrough it. This yields a colorless shellac solution.

The best shellac grades are rated by color and impurity content. The best grades arethe Kusmi and Golden Bysaki crops and are usually shipped to Europe where they are furtherprocessed to yield dry shellacs such as Behlen "Super Blonde".

Many mail order companies sell dry shellac according to color and wax content. The mostcommon shellac sold is #1 Orange and usually contains 4% wax content and is abrownish-orange color. Dewaxed shellacs can range in color from a dark-golden brown to apale amber.

SOURCES OF SUPPLY

Dry Shellac flakes in various grades, padding cloth, Bekhol, and oil can be

purchased by contacting:

Homestead Finishing Products

11929 Abbey Rd. Unit G

North Royalton, OH 44133

216-582-8929

Jeff Jewitt is a finisher, writer and teacher from North Royalton Ohio. In addition torunning a full-time finishing shop, he has written numerous articles on finishing for FineWoodworking, American Woodworker, Popular Woodworking, Woodshop News and ProfessionalRefinishing Magazine. He is currently a technical editorial advisor forProfessional Refinishing magazine, acted as a consultant for large finishing companiesand has developed finishing products which are sold all over the world under the Homesteadname. He is the author of Hand Applied Finishes and two videos, ColoringWood and Applying Topcoats (Taunton Press) and is currently working on a new book dueout in late 1999.

Jeff Jewitt owns and operates Homestead Finishing Products – featuringhard-to-find traditional finishing products. 5 Grades of dry shellac, oils, varnishes,brushes and their own exclusive line of dyes make Homestead Finishing Products a must forevery restorers supply needs. Excellent technical advice. Please contact us by:

Also available are Jeff’s Book Hand Applied Finishes, and two videos, Coloring Wood and Applying Topcoats – winners or the 1997 Stanley Award for best How-To book and video.

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