guys and gals here is an edited reprint of the first offering. as it will appear in the word document when completted ther are some format differaces cause by cut and past but this will have to do for now. i will be submitting the rest of the bodying chapter later this week and Spiriting-off will follow that next week.
Once again I encourage you guys and gals to ask question but as previously stated let try to keep the closely related to the current or previous submissions so that we can go back and look at these things some what in order later down the road.
French Polishing with Michael Payne
Introduction
First, a little about myself before we get started. I grew up in my grandparent’s care. My grandfather was a master carpenter by more than just title, meaning during his life he served an apprenticeship, and worked as a journeyman under the tutelage of master craftsman. He opened his own cabinet shop and put 40 plus years into his craft. During my teenage years and beyond, I worked under his supervision. This is where I learned to French polish. My methods, with the exceptions of pore filling and my choice of solvent are, for the most part, unchanged from what I was taught. My methods are very traditional. I hold on to some beliefs that may be controversial about what makes for a good hard finish. Nevertheless, my technique will provide a smooth, hard, durable finish worthy of a fine instrument or piece of furniture.
What is French polish? French polish is a technique of applying shellac to form a single continuous amalgamation or film. The shellac is applied in steps called sessions. A session may be one process or a series of processes. To truly understand this technique, do not think in terms of coats. The term “coats” implies the application of one layer over a previous layer. In French polishing, we will build one continuous amalgamated film in a series of processes performed in a series of sessions.
Not counting pore filling, the three basic processes of French polishing are: Bodying, Spiriting-Off, and Glazing. Here is a brief explanation of each of the processes.
Bodying Bodying is a process of applying shellac via a muneca or pad in overlapping figure eight or circular motions; this process is much like applying wax to a car or paste shoe polish to a shoe. Spiriting-Off Spiriting-off is a process of using a straight stroke with a muneca or pad that is loaded with only residual shellac in the pad and a few drops of solvent. This process melts high spots left from a previous bodying session and removes residual lubricant oil.
Glazing Glazing is a process of applying a more diluted cut of shellac in a straight or buffing motion that adds a high gloss to the film.
The supplies needed: There are many acceptable substitutes for some of the supplies. However, I will only mention the ones I personally would use.
• 100% dewaxed shellac flakes or pre-mixed shellac - such as Zinsser’s Bulls Eye Seal Coat 100% dewaxed shellac.
• Denatured Alcohol - denatured with no more than 5% methanol or 180-proof Pure Grain alcohol from a liquor store.
• 4-6 oz of 100% pure Walnut oil or Extra Virgin Olive oil.
• Many 4” x 4” well worn non-dyed Muslin or linen squares (for the outer muneca or outer pad).
• A couple feet of non-dyed 100% wool roving (for the inner muneca or pad).
• Three 2-4 oz plastic bottles with caps (for bulk shellac and oil storage).
• Three eye dropper bottle with eyedropper (one for 2# shellac, one for 1# shellac and one for the lubricant oil, each used to store shellac or oil for loading the muneca).
• Small natural bristle artist brush.
• A supply of 8.5 x 11 printer paper.
• A good medium- to high-intensity work lamp.
• A lint-free work pad, like a well worn folded linen sheet.
• A good bit of patience and determination.
Preparation of the finish media. If you are making your own cuts of shellac you will need to make up two different cuts or mixes of shellac. You will need a 2# cut for sealing and bodying, and a 1# cut for initial seal coat and glazing. I use Zinsser’s Seal Coat pre-mix because I like the slight amber tint. It is store-bought 100% wax free sealing shellac premixed, and works very well for French polishing. Its color is a 50% blonde and 50% amber or garnet blend. It gives a nice warm vintage but not dark tint to the wood. It comes as a 2# cut straight from the can. I cut that with 25% per volume with alcohol to achieve a near 1# cut. I make up 2 oz. at a time and store it in the plastic 2-4 oz. squirt bottles mentioned in the supply list.
Make up at least 6, 4” x 4” outer pads from well-used white muslin or linen. Others often suggest T-shirt material, but I find it causes ridges during bodying due to its 3-D stretchable weave.
I prepare my inner munecas a day in advance. These are made from 100% wool roving and I use enough material to make tight golf ball sized pads when dry. To prepare them I first set balls of wool roving on a piece of wax paper in a bowl and saturate them with 2# cut of shellac. I then allow them to stay in the open-air bowl for about 2 hours. At this point, I put on nitril gloves and roll each ball in the palm of my hand over the bowl until no shellac drips from it. Each should be about the size of a ping-pong ball or slightly smaller at this point. Then I place each ball into a zip lock bag with the seal half open overnight or until the balls are the consistency of soft taffy, then seal the bag airtight. At this point, the inner munecas are ready to use.
Once an inner pad is ready to use, wrap it in one 4” x 4” outer pad, bundle it tight as possible and secure it with twine or a rubber band. Keep in mind that you will be changing the outer pad every so often, so you want to be able to remove whatever you use to bind the inner muneca.
A little note of interest: the word muneca is Italian for rag doll in reference to the pad having the appearance of rag doll’s head.
Prepping the work surface Naturally you will want your guitar body or other type of work surface to be prep sanded, pore filled, grain raised and sanded back, ready to seal. If there is any colored purfling that needs to be sealed to protect from bleeding woods, this should be done first with a 1# cut of shellac and a fine artist brush. If any bleed over occurs during sealing, it can be scraped off with a razor blade or a small cabinet scraper, then resealed with shellac. I seal in this order: purfling, top, and then back and sides.
An initial spit coat is applied much as body sessions will be later, but a tad wetter. After any purfling has been sealed with a brush if needed, load the muneca up with 4-5 drops of 1# shellac, 3-4 drops of alcohol and 1-2 drops of lube oil. Then tap one time on a sheet of white printer paper. This forces the alcohol and shellac into the inner pad and starts the wicking process of the residual shellac in the inner pad. Start on the top and cover the top evenly with short figure eights until the top is evenly covered with shellac. Be sure to reload the pad as soon as you start to feel drag. You do not want the pad to ever stop or slow down as you are working. If it does, it will stick, causing a lumpy buildup. After the top, do the back, one side, and then the other, allowing about 10 minutes of cure time before moving on to another surface.
This spit or seal coat is the foundation of the future body sessions. It goes on wetter than the body session will, and is done so that the drier, first body session has a base to melt into. The spit coat does not need to be very thick at all. It just needs to cover the entire surface area.
Bodying:
First let’s start with a brief understanding of what bodying is and is not.
Bodying is the application of residual shellac on the work surface that is semi-hard and shellac entrapped in the inner pad onto the surface by means of melting a portion of this residual semi-hard shellac with a fresh load of shellac and alcohol migrated to the outer pad by tapping the pad on a piece of paper, causing a wicking process to allow the residual shellac in the inner pad to flow through the outer pad and onto the work surface.
Bodying is not the application of a wet fresh load of shellac loaded onto the outer muneca and spread around or painted on.
Telltale signs that the muneca is properly loaded: With this in mind there are two key telltale signs that indicate if you have the muneca properly loaded and if wicking is happening properly. The first sign to look for is right after you load the muneca with a new load. This load should be 4-5 drops of 2# shellac, 3-4 drops of alcohol, and 1-2 drops lube oil. Then tap the newly loaded muneca on white paper until the stain (referred to as “report” from here on in this tutorial) is spotty and not solid. This is the first telltale sign. It tells you that the muneca is loaded and prepped for bodying.
The second telltale sign is displayed during bodying. For an example of this next telltale sign, take your safety glasses off and breathe on them. Notice the water vapor from your breath appear and disappear quickly. This is water flashing off a dry surface. When we body, we want to see alcohol doing the same thing, as the muneca moves along the work surface. Seeing (or not seeing) this sign really tells you several important things. First, it tells you whether the wicking action is (or is not happening) and second, whether your load has too much or too little shellac or alcohol. Be aware that the vapor trail is a fleeting thing. It will last only a brief fraction of a second at any given point, and you should be watching for it at all times. It should extend for about ½” or more behind the muneca as it moves.
If there is no vapor trail but a thick wet trail behind the muneca as it moves that does not disappear quickly, this tells you that you have loaded the muneca with too much fresh shellac.
If you see a thin wet trail that disappears fairly quickly. but not instantly, this tells you that you have loaded the pad with too much alcohol. If there is no vapor trail and no wet surface behind the muneca then you have too little alcohol in the load.
Do not confuse wet shellac as a vapor trail. Once again the vapor trail will appear and disappear just like the fog you see when you breathe on your safety glasses.
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