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For further information please contact us at: sales@shellacfinishes.biz
Shellac FAQ
What is a shellac'cut'?
The so called 'cut' of shellac is best described as the ratio of shellac flakes in relation to denatured alcohol. A 1lb 'cut', means 1lb of shellac flakes dissolved in 1 gallon of denatured alcohol. However this is a large quantity for most woodworking shops. Moreover most shops do not own a weighing scale either. Hence a smaller amount can be mixed for a 1lb cut by taking 1oz. of shellac flakes and dissolving it in 1 cup of denatured alcohol. If a 2lb cut is required, simply increase the weight of the shellac flakes to 2oz. For a 3lb cut increase the weight to 3oz and so on for heavier cuts. Since a cup holds 8 oz, divide the cup into eight equal parts for measuring 1 oz. now you don't need a weighing scale, only a cup from your kitchen.
How do I make the shellac solution?
Take a clean glass bottle with a tight fitting lid that will hold the amount of alcohol that you intend to use. Use the above measurements for the shellac flakes and alcohol depending on the cut and quantity that you want to make. Pour the shellac flakes and alcohol into the bottle and close the lid tightly. Give it a few shakes from time to time. The shellac will dissolve in a few hours. Run the solution through a paint sieve, that can be found at any paint store, to remove impurities. You are ready to apply shellac.
Are there any benefits to using pure alcohol over denatured alcohol?
Not really, except the price you pay for the alcohol!!
How is shellac applied?
Shellac can be brushed, sprayed, padded or French polished. Padding and French polishing require practice and patience. Brushing and spraying are the easiest methods. Use a good quality animal hair brush for minimizing brush streaks. For sealing insides of drawers and furniture, brushing is the best way for a quick and easy application.
How do you determine the weight of the cut for different applications?
A 2lb cut is common and used for most applications like coating of insides of drawers and furniture. For a final coat of Super Blonde over Garnet, Orange or any other variety, a 1lb cut is usually used. Shellac can also be used as grain filler for open grained woods like Oak, Mahogany etc. Use a 3lb cut mixed with a few tablespoons of fine grain Rottenstone/pumice powder to form a goopy mixture. Apply mixture liberally on the surface pressing it in with a pad or a ball of cloth. Wipe excess off. Let dry for 24 hours and wet sand lightly with Naphtha as a lubricating and cooling agent. If grains are not fully filled, repeat application. Run your finger nail across the grain. If it travels freely, it indicates that the grains are filled.
Can shellac be used as a stain?
Absolutely. As a matter of fact it is a stain and a sealer all in one. You can't ask for more! If you wish to use shellac as a stain, simply take Super Blonde, which is the clearest of all grades, and mix the required alcohol based aniline dye till the desired color is achieved. Here is an example. The drawer pulls on my tool chest are Maple but tinted as Walnut.
Can shellac be used as a sealer?
Shellac is an excellent sealer. Always apply a coat of shellac on the insides of cabinets and drawers. If the wood has been finished with any kind of oil and the odor needs to be rid off, use shellac as a sealer. Ever tried applying a coat of paint over pine wood? Over time, the sap leaches out and ruins the look. Use shellac as a sealer coat before applying paint.
Is shellac non toxic?
Yes it is non toxic and can be used on any children toys or furniture. Please keep in mind that once the alcohol evaporates, only shellac remains on the toy or furniture. Shellac is widely used in the candy, cosmetic and drug industries as a coating for finished products.
What is the shelf life of shellac?
Shellac flakes have a finite shelf life unknown to most users. Even if Shellac flakes are stored in a cool, dark and dry place, but older than 3 years, it will not dissolve in alcohol overnight when compared to fresh stock. When applied, it will be sticky and slow drying. If used for French polishing, more than the usual amount of oil will be required for lubrication.
Once dissolved in alcohol, shellac does not last more than 6 months at the most. Store mixture in a cool dark and dry area of your workshop. The ideal temperature is between 65-70 degrees F.
Always dissolve shellac as and when needed.
Here is some data collected by testing flakes from Shellacfinishes and a major brand. The testing was done by Matt Ebner.
Superblonde shellac ----
Saturday, Dec 13, 4:30 PM: Weighed out 56.9 grams (2.0 ounces)
Superblonde shellac. Placed flakes into a quart small-mouth canning
jar with a rubber-seal lid. Added 8 fluid ounces (1 cup) of
denatured anhydrous ethanol (volume measured with kitchen glass
measuring cups, as I have broken my metric graduated cylinders some time ago -- expect that the volumetric error is about 5%). Sealed the jar, shook thoroughly for about 30-40 seconds. Temperature was 68 F.
5:50 PM Supernatant ethanol has taken on a slight light tan color,
indicating the beginning of the dissolution process. Flakes formed a
loose layer about 1 cm thick at bottom, was easily re-suspended with shaking of the jar.
7:30 PM Color of supernatant had intensified somewhat; shellac was now a gelatinous layer about 8 mm thick at bottom of the jar. Shook jar thoroughly, repeatedly upending the jar, was able to break up and re-suspend the gelatinous layer easily by very vigorous shaking. Room temperature = 68F.
8:20 PM Gelatinous shellac layer seemed thinner, probably 6 mm thick. Again, the gel layer was easily broken up and resuspended by vigorous shaking. Room temperature = 68 F.
10:30 PM Gelatinous shellac layer at bottom was about 4 mm thick,
easily re-suspended by vigorous shaking. Temp = 65F
Sunday Dec 14, 8:40 AM Superblonde shellac was almost all dissolved, with no soft gelatinous layer at the bottom of the jar. Did observe a very fine precipitate of fine solid particles at the bottom that formed a discontinuous layer much thinner than 0.5 mm. Solution is very turbid and almost opague due to very fine suspended solid particles. No evidence of any suspended gelatinous material. Overnight room temperature was 55F
10:30 AM Very turbid solution, opague enough that one can see only 1 cm into it. Temperature 60F.
12:20 PM Same, very turbid and opague. All of the shellac has
definitely dissolved, and no suspended gel particles are visible.
Temperature 68F.
Conclusion: The Superblonde shellac dissolved rapidly at room
temperature (including the overnight dip to 55 F!!!) in less than 16
hours! During the dissolution, the shellac did NOT form an adherent gelatinous layer at the bottom of the jar; it was always possible to break it up and resuspend by vigorous shaking.
Beige shellac ----
Saturday, Dec 13, 4:40 PM: Weighed out 56.8 grams (2.0 ounces) of Beige shellac into a quart small-mouth canning jar with a rubber-seal lid. Added 8 fluid ounces of denatured anhydrous ethanol. Sealed jar and shook thoroughly for about 30-40 seconds. Temperature = 68F.
Shook the Beige shellac test at the same times as the Superblonde
shellac. The temperature conditions were the same, as the two jars
were placed side by side. The gelatinous layer at bottom of jar was
firmer, more adherent than the Superblonde, but was able to break up and re-suspend with very vigorous end-to-end agitation. Solution color was much slower to develop than the Superblonde, even though the Beige is darker.
10:30 PM Soft gel layer at bottom of jar was about 6 mm thick,
definitely thicker than the Superblonde. Layer was firm and adherent, had to break up by manual stirring.
Sunday Dec 14, 8:40 AM Soft gel layer at bottom of jar, less than 1 mm thick. The layer was easily broken up and re-suspended by vigorous shaking (no stirring needed). Supernatant solution is dark brown color, very turbid and totally opague; less of the fine precipitate particles are visible in the Beige than in the Superblonde.
10:30 AM Shellac has dissolved completely, no gel layer or gel
particles visible.
12:20 PM No change
Conclusion: The Beige was initially slower to dissolve than the
Superblonde shellac, but did go into solution in less than 16 hours
despite the low overnight room temperature.
I have experience only with a major brand blonde shellac. With the this brand of shellac, I have had to use anhydrous methanol (Ace hardware) to dissolve the shellac; I could not get the shellac to dissolve in anhydrous ethanol in a reasonable length of time. Even with anhydrous methanol, complete dissolution of this brand shellac generally required almost one week (with frequent stirring). or in fresh anhydrous Ace brand methanol. This brand of shellac formed a gum deposit at the bottom of the jar that had to be broken up with forceful stirring, and after 3 days at 68 F dissolved about 30 to 40% of the shellac as judged from the mass of gelatinous shellac deposit on the bottom of the jar, in both ethanol and methanol. It was then heated for 3 days in a double boiler to about 120-130F in the loosely-sealed jars, but neither dissolved completely. Both jars had a lot of gelatinous stringers and globs of shellac at the bottom of the jars and in suspension; the suspended material was easily visible in the solutions. The ethanol solution of this brand was then filtered through coffee filters to remove the suspended gel mass. Filtration of the suspension plugged two coffee filters (in sequence) with less than half of the solution filtered; the remaining solution was filtered through an old T-shirt scrap. A lot of gelatinous shellac was trapped on the filters. This brand of shellac in anhydrous methanol was kept sealed; I compared the Shellac Finishes Superblonde and Beige tests against this brand of shellac during the course of the test. While both Shellac Finishes shellacs dissolved in less than 16 hours, the major brand shellac in fresh anhydrous methanol still had undissolved, gelatinous stringers and globs in the bottom of the jar (probably 10% of the original mass, allowing for the lighter density of the gel).
Overall observations: The Shellac Finishes Superblonde and Beige
shellacs dissolved in denatured anhydrous ethanol in less than
16 hours at temperatures that ranged from 68 F to 55 F! By comparison, the major brand blonde shellac generally requires almost one week to dissolve to a similar extent using anhydrous methanol rather than ethanol. In fact, my latest batch of this brand dissolved only about 50% in anhydrous ethanol after 3 days of heating to 120-130 F, and incompletely in anhydrous methanol after more than 2 weeks at room temperature and 3 days at 120 F.
I am ecstatic with the ease of dissolution of your shellac product. I
am only a hobbyist woodworker and wood turner, but I will surely spread the word "
Are any discounts available?
Yes, if you are a member of the following organizations:
1) San Diego Fine Woodworkers Association (SDFWA)
2) North Carolina Woodoworker
3) St. Louis Woodworkers Guild
4) Palomar College, Cabinet and Furniture Technology
You are eligible for a 10% discount. Please use the coupon code that can be obtained from your association. Code is entered during checkout.
If you would like to include your organization in the above list, please send your enquiry to sales@shellacfinishes.biz
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