How to Buy Shellac

It is essential to always use fresh shellac. Once the can has been opened, the contents will deteriorate within six months to such an extent that they will not dry after application. Even in cans that have never been opened, shellac deteriorates, which is the reason that many manufacturers date their products. When buying shellac, check the date, and do not buy the product if it has exceeded the expiration date. If you are offered undated cans, buy them only with the understanding that you will get your money back if the contents do not dry as they should.

The "Cut" The resinous shellac is dissolved in denatured alcohol, and the proportion of resin to alcohol is called "the cut." Thus, when you sec a can marked "l-pound cut," it means that the contents consist of shellac cut at the rate of three pounds of shellac resin to one gallon of alcohol. The 3-pound cut, which is the right consistency to be used straight from the can for finishing floors, is the most common cut found in stores. The best cut to use for furniture finishing is the l-pound, which brushes on easily and dries quickly.

The more shellac resin in the mixture, the thicker the coat laid down each time. It is true that with a l -pound cut you have to apply more coats than with a 2-pound or 3-pound cut, but since brushing is easier, the l-pound cut works best, particularly for novices and their early efforts. Later, after gaining experience, you may want to shift to heavier cuts.

You build a shellac finish coat by coat. As a rule, most finishers using a l-pound cut would plan on three to five coats. Since shellac dries hard in half an hour (up to an hour in higher humidity and lower temperature conditions), you can apply these coats quickly, usually finishing the entire job in a day or two.

Types of Shellac Shellac comes in white and orange. White shellac is clear and is the one usually used in furniture work. Orange shellac tends to darken light woods, and will give darker woods a richer look.

Mixing with Denatured Alcohol When you buy shellac, also buy the denatured alcohol you will need to thin it. Use the accompanying chart to find out how much alcohol to mix with each "cut" of shellac in the can to get the cut you need for your work. As you can see from the chart, you can start with any cut, so it doesn't make much difference which one your dealer sells. Look in the chart for the cut you bought. Glance down the left-hand column to the cut you intend to use. The chart indicates how many parts of alcohol to mix with the ingredients in the can to get the cut you desire. If you buy 3-pound cut shellac, and want to w:ork with 1-pound cut, the chart shows that you should mix three parts of shellac with four parts of alcohol.

PROPORTIONS FOR SHELLAC CUTS

Shellac

Alcohol

Resulting Cut

2 parts 5 lb.

1 part

3 lb.

1 part 5 lb.

1 part

2 lb.

1 part 5 lb.

2 parts

1 lb.

1 part 4 lb.

2 parts

3 lb.

4 parts 4 lb.

3 parts

2 lb.

1 part 4 lb.

4 parts

1 lb.

5 parts 3 lb.

2 parts

2 lb.

3 parts 3 lb.

4 parts

1 lb

Wood Working for Amateur Craftsman

Wood Working for Amateur Craftsman

THIS book is one of the series of Handbooks on industrial subjects being published by the Popular Mechanics Company. Like Popular Mechanics Magazine, and like the other books in this series, it is written so you can understand it. The purpose of Popular Mechanics Handbooks is to supply a growing demand for high-class, up-to-date and accurate text-books, suitable for home study as well as for class use, on all mechanical subjects. The textand illustrations, in each instance, have been prepared expressly for this series by well known experts, and revised by the editor of Popular Mechanics.

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