FINISHING SECRETS . . .|
10. Friction Polishes
These finishing products are an attempt to get quick and easy "French type" polish on spindle turnings, weed pots, vases, and other small items. They are either shellac or lacquer based, and contain waxes and oils. They will never equal the durability of a true French Polish, and they are often not as easy to apply as advertised.
BACK TO "RUSS'S CORNER" INDEX
BACK TO "FINISHING SECRETS" INDEX
There are several commercial friction polishes available with either a shellac or lacquer base - Shellawax®, Behlen's Woodturners Finish
®, or others. I have had the best results from the liquid Shellawax
®. It is a shellac product that is easy to use and it makes a very high gloss finish when you follow the directions. Similar results can be had with other products and homemade friction polishes, and these will be discussed later.
Don't expect to get perfect results the first time, even if it is advertised as easily done. Getting good results, particularly with shellac based products, takes as much practice as getting a good French-Polish with the techniques described in Part 9 of this series.
There are several techniques that will increase the probability of getting a good finish with any Friction Polish.
Again, I prefer to use my own mixtures because they are just as good as, and a lot cheaper than the commercial products. If you are into experimenting with finishes; a shellac based friction polish can be mixed from equal parts of shellac, denatured alcohol, and boiled linseed oil. Add a little beeswax, about a teaspoon full to ½ pint of finish. Heat the wax in the microwave to soften it before adding it to the finish. The oil will not mix with the alcohol, so you will have to keep it stirred. The commercial products get around this problem by homogenizing the mixture.
- A friction-polish is not a miracle product. The finish will only be as good as the surface you put it on. The wood surface must be as near perfect as we can get it because the high gloss will also magnify every defect and things we thought were insignificant are suddenly obvious. Sand to at least 600 grit, and 1500 is even better. Remove all sanding scratches and circular rings.
- Heat is required to "flow" the finish and make a smooth finish. High lathe speed isn't necessary as long as there is enough pressure and friction to generate the heat. The applicator should be just below the temperature where it is too hot to hold. In other words, when your fingers start to burn, you are there.
- Do not flood the surface with the finishing solution. Use just enough to cover the surface for the first coat. Then add small quantities as each previous coat dries, and continue to run it until it is dry and gets hot before adding more finish. This is a case where minimal is the right amount.
- If ridges in the finished surface are a problem, adding more finish is not the solution. We may already have too much. Add denatured alcohol to the applicator if it is a shellac polish, and lacquer thinner if it is lacquer. The thinner will soften the surface, and allow us to "flow" the finish with friction heat.
- We must use an applicator that will not impart a surface texture to the finish from the weave of the cloth, or hardened finish on its surface. I have found the best applicator to be a piece of new velour towel. It doesn't have to be white, but it has to be new. Washing leaves a detergent residue that can affect the finish, and drying hardens the ends of the cotton fibers. The soft velour will form a smooth matte in the friction area that is free of any texture. Rather than break-in a new applicator every time, store it is a small jar with just enough denatured alcohol to cover the bottom. The excess alcohol will evaporate from the heat the next time it is used.
A lacquer based friction polish can be made from equal parts of Deftâ gloss lacquer, lacquer thinner and boiled linseed oil.
This discussion has been based on the traditional application of a friction polish with the wood spinning in the lathe. This works very well for small pieces up to about 6" diameter. It does not work well for larger bowls or platters.
Enter the power sander with a 2" sanding arbor and a 5" square of the same new velour toweling that was described in Item-5 above.
Put an 80-grit disc on the arbor to grip the velour, wrap the velour square around the sanding disc with the face side out, and hold the corners with a rubber band or a small tie-wrap. Hold the work stationary in the lathe, or other means. Then dampen the pad with the Friction Polish. Run the drill at approximately ½-speed, and work the pad across the surface. Recharge with more Friction Polish when it starts to get dry and "grab" on the surface.
When there is a uniform coat on the wood, continue working the pad at the same speed until the surface of the pad is dry and feels hot to the touch. Stop when there is a uniform high gloss. Lift the spinning pad from the surface before stopping the drill rotation.
Apply a small amount of the Friction Polish around the perimeter of the pad, and repeat the application.
© 2002 - 2009 by Russ Fairfield. All rights reserved.
No parts of this publication may be reproduced in any form
or by any means without the written permission of the author.