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Orville and Robert Milburn
Materials
The tools and materials used in French polishing are few and very simple. As a matter of fact, for an investment of a few dollars you can obtain all that is needed to finish a number of instruments. At the end of this article we will list some merchants where dependable materials may be purchased.
SHELLAC
Lac is a natural substance that is secreted by the insect "Coccus lacca" often referred to as the lac beetle. This substance is collected from a variety of trees that play host to the insect. The Lac is taken from the tree branches and bark. The harvested lac is cleaned and processed into a variety of different forms including hand processed (shell lac) which is scraped from heated bags of lac.
Shellac flake on left and ground shellac on right. The shellac flakes were ground using a coffee grinder. Shellac is non-poisonous and is approved for use in food by the FDA. |
The bags of harvested lac are heated over an open fire. As the lac melts, the bags of lac are squeezed with a tourniquet producing enough pressure to force the melted lac to the outside surface of the bag. Much of the lac is processed into thin sheets which are crushed into brittle flakes for preservation and storage. Most of the shellac is used for industrial purposes while some of the shellac is processed into ready-to-use finishing material which can be purchased in most paint or hardware stores. A great deal of the shellac flakes are processed and sold to professional finishers who specialize in beautiful hand rubbed finishes. Over a period of years the term "shell lac" has become known as "shellac." For one of the finest articles and complete description on how shellac is harvested and processed, you may want to obtain a copy of "American Lutherie No. 54, summer 1998." The article was written by Cyndy Burton, who is one of America's finest luthiers and French polishers. The shellac that we will be using is sold in flakes. The flakes are available in at least four types. The type of shellac denotes the color, from light to very dark, usually referred to as "white," "blonde," "orange", and "dark" (or "garnet"). The shellac flakes are then dissolved in alcohol only as needed. The reason for this is that dissolved shellac has a short "shelf- life." When a mixture of shellac and alcohol sets for a long period of time it collects moisture and undergoes a chemical degradation called hydrolysis. It is desirable to mix only what you plan to use in a few months time. Never use pre-mixed, canned shellac from the store for French polishing. Ready-mixed shellac is composed of number of additives designed to extend its shelf life, increase flow, and retard drying time so that it can be applied using a brush. Even though most ready mixed shellacs are of very high quality, the additives that they contain are not suitable for French polishing. Purchase only high quality shellac flakes from a trusted merchant. We will list names and addresses where shellac flakes can be purchased at the end of this article
ALCOHOL
We will be using a lot of alcohol. The alcohol will be used for dissolving shellac flakes, thinning, pore filling and other French polishing procedures. Good quality hardware store alcohol is all that is necessary. Some people, however, are sensitive to the materials that are added to the alcohol in the denaturing process. Denatured alcohol is ethanol to which has been added a small amount (about 5%) of a poisonous alcohol (usually methanol) Above all, keep denatured alcohol out of reach from children and locked in a safe place. If you are concerned, you may wish to purchase pure alcohol from the liquor store. The only drawback of this approach is that you will pay a lot for the pure ethanol. There is a small concern that some denaturing agents may cause problems with the rate at which the alcohol evaporates. Read the labels on the alcohol you buy and purchase ethanol that has been denatured only with methanol. Again, we will mix only what is required as we work. An open container of alcohol will draw moisture as it evaporates and break down its purity so keep lids or caps on all bottles.
PUMICE
Pumice is used for grain and pore filling and is also used as an abrasive at certain times during French polishing. Pumice is often used as a polishing compound for many other types of finishing and is available in specialty paint stores. We use FFFF grade (F stands for floated. Fine pumice particles stay suspended in solution for a longer period of time and thus have a larger "float" grade) pumice which is very fine. Pore filling and the use of pumice can be a difficult part of French polishing early on. Once learned however, the job will be straightforward and almost effortless.
These are the main materials used for French-polishing. The containers are chosen to aid in dispensing proper amounts of the various materials. |
OIL
Olive oil is used as a lubricant as we French polish. The shellac is applied using only the muneca or folded pad. The muneca must be pressed very firmly against the surface of the wood in order to dispense the shellac properly. This firm pressure also "amalgamates" each microscopic layer of shellac with the previous layer making it possible to "build" a rich and seemingly deep finish- and one that is quite hard. The judicious use of oil allows one to press hard and firmly against the wood without the muneca sticking or dragging. As the shellac is laid on the surface the oil will tend to permeate through the finish and rise to the top. It is therefore important to use only oil that will not get trapped under the shellac and destroy the finish. It is advisable to use only pure 100% virgin olive oil. Other oils such a walnut oil, baby oils (mineral oil), and some paraffin oils can have additives such as antioxidants and perfumes that can create problems with the finish itself. The beginner should use only pure olive oil before he or she experiments with other lubricants
ABRASIVES
We will be covering some detailing and preparation of the guitar for French polishing as well as the polishing itself. We will include all grades and type of abrasives needed as follows:
- 220 grit open-coat dry sandpaper 3M "Gold" 216U
- 320 grit open-coat dry sandpaper 3M "Gold" 216U
- 400 grit wet/dry automotive sandpaper 3M "Imperial 401Q
- 800 grit wet/dry automotive sandpaper 3M "Imperial" 401Q
- 1200 grit wet/dry automotive sandpaper 3M "Imperial" 401Q
- Micro-Mesh "Cushioned abrasive" 3200
- Micro-Mesh "Cushioned abrasive" 3600
The above abrasives should be all that you will need to complete your first French polishing project.
Here are some of the sanding blocks we use in leveling the finish. In the back is a large wooden block with a cork pad. Next to it is a mahogany block with a round edge to smooth the inner surface of the string slots. Also shown are various rubber blocks. Some are made of pink pencil erasers. Note the various sizes and shapes. |
CLOTH
We will be constructing a rubbing pad or "muneca" (Spanish for rag doll) using wool or surgical gauze for the inner pad and an outer covering of a soft 100% cotton cloth such as t-shirt material. The composition of wool or gauze is ideal for retaining the shellac inside the muneca until it is forced out by the pressure of the hand. Be sure that you use only pure wool or clean cotton gauze for the inner pad or the shellac may not dispense properly. Do not use any synthetic or synthetic blends for any of the muneca components. A well-worn t-shirt is ideal for the outer covering and a cut up wool sock is suitable for the inner pad. Have plenty of soft wiping clothes ready as well. You may want to purchase about a yard of t-shirt cloth from a local fabric store or, better yet, procure a couple of well worn t-shirts. This should be more than enough for the first project. Note that any material that comes into contact with the guitar must first be checked for foreign particles, dirt, etc. Even a tiny speck of dirt can cause visible scratches in the newly applied finish. The finish will be extraordinarily fragile until it hardens.
CLEANING AND POLISHING AGENTS
As we stated before, no polishing compounds or polish is used in the actual French polishing process as we lay on the shellac. When we are finished however, we will need to remove excess oil and clean and polish the instrument to rid it of hand prints. For this we use "Meguiar's No. 7 Show Car Glaze". The Meguiar's #7 contains no abrasives so it is safe for repeated use and maintenance of the finish. If a more aggressive cleaning agent is needed, we will use a very fine rubbing compound such as "Meguiar's #9 Swirl Remover". The Meguiar's #9 contains a very fine abrasive and will remove some finish. Use it to remove tiny scratches. It cannot be used for finish maintenance. These are very high quality products which contain no silicone compounds that may damage the finish or the wood itself. They can be purchased from automotive supply/parts store or auto paint specialty stores.
MISCELLANEOUS ITEMS
- A 1" wide x 1& 1/4 long x ?inch thick rubber block for sanding. A perfectly square wood block with cork glued to the bottom will do as a good substitute. Most any paint store will have rubber sanding blocks that can be cut into smaller blocks. You may also use rubber easers from a stationary store for smaller, ready-made sanding blocks. As a matter of fact, we have a variety of easers of many different sizes and shapes for this very purpose. Be sure to glue the cork using epoxy because the oils and solvents may loosen other types of glues.
- Small squeeze bottles for dispensing the shellac and alcohol are important. Small glue bottles can be purchased at many paint and tool stores and are ideal. You will need at least two squeeze bottles
- A small bowl with an air-tight lid is desirable for storing the muneca and other dispensing clothes to keep them from drying out.
- A salt shaker for dispensing pumice.
- A medicine dropper bottle to dispense oil (purchased from a pharmacy).
- One quart of naphtha solvent.
- Guitar neck rest. Many times while French polishing, the guitar needs to be supported at the neck because of the downward pressure exerted on the top.
- SuperGlue and 5-minute epoxy.
- A stop-watch
- A small funnel
- Typing paper
Finally, you will need a place to work. You may want to set aside a small, well-lighted area or use a spare room in your house to work on your project. An even temperature and a dust-free area are desirable for French polishing. Ideally, the area would be in a corner to help reduce drafts that carry dust (air-carried dust is only a concern late in the process) We have assembled about all that we need for our French polishing project, so let's get started . . .
Detailing the guitar
The quality of any finish will depend greatly on how well the instrument is detailed. The finer the finish you are going to use, the more any defect will show. Our purpose is not to teach wood working so we will assume that the guitar is well scraped, sanded and with all gaps filled. All of the purflings and bindings should be perfectly level and flush.
Detailing the guitar edges with a sanding "stick". |
Using cyanoacrylate adhesive (SuperGlue) to fill small defects in the rosette. |
Dissolving the shellac
It's time to prepare our shellac. Because the next step will require the proper "cut" of alcohol and shellac flakes, we will need to know how much alcohol and shellac to mix together in order to obtain the proper cut. A 1 pound cut means we 1 pound of shellac flakes are dissolved in 1 gallon of alcohol. If we want a 2 pound cut (thicker or heavier), we will add 2 pounds of shellac flakes to one gallon of alcohol. As we have stated before, it's never a good idea to mix more than can be used in a short amount of time. Besides, only a pint of a 2 pound cut is enough to French polish an entire guitar. Let's reduce the mix proportionally by dividing both the shellac and the alcohol to a manageable amount. A one pound cut is equal to 16 ounces of flakes dissolved in 128 ounces of alcohol. This is the same as 1 ounce of flakes dissolved in 8 ounces of alcohol. Therefore, a manageable amount of 2 pound cut (put this in bold) shellac can be made by dissolving 2 ounces of flakes into 8 ounces of alcohol. It's important to note that, at this point, we won't be too concerned about the exactness of the proportions since it is not that critical to the quality of the final mixture.
Various shellac solutions. From far right: Very thin cut of "luna" shellac, 2-pound cut of "luna", 2-pound cut of garnet shellac, olive oil for comparison. |
You may mix the shellac flakes with alcohol and let them sit for 24 hours until they are throughly dissolved, or you can prepare the shellac for almost immediate use by grinding the shellac flakes into a fine powder with a coffee grinder or blender. The powder will dissolve into the alcohol many times faster than the solid flakes. Occasional gentle agitation or moderate heat will help speed the process. Use as water bath to heat the mixture, but do not use a range or hot-plate. Using this method will allow you to have a shellac solution ready to use in a few hours. Once dissolved, the shellac can be transferred to your squeeze bottle.
Just a word of safety...
- Do not allow smoking in the same room where you will be working.
- Do not work in a room with open flames such as wood stoves and appliances with pilot lights
- Be sure that there is adequate ventilation in the area where you are working.
- Keep the shellac and alcohol locked up if children are visiting or live in the same household.
Equivalents:
1 ounce = 30 grams
1 gallon = 128 ounces or 3840 grams
1 gallon = 8 pints
1 pint = 16 ounces or 480 grams
Seal-coating the guitar
We are now ready to apply a base for the French polish. This base is what is known as a "spit-coat", "wash-coat", or "seal-coat" of shellac. The purpose is three-fold. First, it provides a bonding surface for the many microscopic layers of shellac that we will be applying to the guitar. Shellac is known as the worlds best wood sealer because of it's high bonding properties. Second, it will help protect the inlays, purflings, and the rosette from color contamination due to the oils and dyes in the back and sides of the guitar. Third, this base of shellac will combine with the pumice and natural wood dyes binding them into the pores of the wood.
Sealing the edges of the back of a rosewood guitar. You can easily see the seal coat left by the wet pad. |
Sealing the edges of an instrument. Note the "field" is already sealed. Here we are sealing the purflings and bindings a second time. |
An example of a folded pad after it has been used to seal a section of a guitar edge. This coloration will contaminate white purflings and light wood. |
Removing purfling contamination using a small scraper made from a heavy single-edge razor blade |
Filling the grain and pores
Pumice is of volcanic origin and has been around for hundreds of years and used for a variety of purposes. Before modern technology developed the fine sandpapers that are common in the marketplace today, pumice along with many other materials were used as abrasives. The wood finisher used a felt block and often a leather-covered block with pumice powder to sand the wood smooth. Pumice was also used to polish shellac and resins to fine high-gloss finishes. The pumice for the wood finisher was ground and filtered into many different grades and sizes much the same way as we buy different grades of sandpaper today. No doubt, at some time during sanding, it was discovered that the pumice not only acted as an abrasive but filled the wood grain at the same time. The pumice method of grain filling has been with us for hundreds of years and is still the preferred method of grain filling for many wood finishers.
Lets start our grain filling now . . .
After sealing the instrument is allowed to "gas out" (remaining alcohol is allowed to evaporate) for a few hours. We are then ready to fill the pores and grain. This is the pumicing operation. At this point we should mention that there are some species of wood that do not require grain and pore filling. The top of the guitar will not have to be grain filled. Spruce, Cedar, and Maple are examples of "closed-pore" woods which do not have to be grain filled, and with some experience you will recognize woods which require grain filling and those that do not. Most rosewoods have large, open pores and will need to be filled. If the pores of an open-pored wood are not filled properly the finish will slowly shrink back into the pores. The result will be thousands of tiny craters in your finish.
Applying the Pumice
We will not be using any new shellac during the entire pumicing process. This is very important- additional shellac during the pore-filling process will inhibit the operation. We will be using the already dry shellac "spit coats" that we have previously applied to the guitar. All that is used is the muneca loaded with alcohol and a very small amount of pumice applied to the muneca surface.
The muneca is touched to a bit of pumice on paper. The pumice is then distributed over the surface of the muneca with a finger. |
The actual pumicing procedure is simple and is as follows . . .
Add a generous amount of alcohol to the surface of the muneca. Be careful not to overdo the alcohol (about 10 to 12 drops is what we call generous). You will always have to add extra alcohol to a dry muneca. Once wet, however, just a few drops(4 or 5 for each recharge will be enough). Note that we will always load the muneca from the outside. Tap the muneca against the back of your hand to help distribute the alcohol throughout the wool pad. Fill your salt shaker with pumice and sprinkle a small amount onto a sheet of typing paper. Now, use the bottom edge of the muneca to "bite" off a small portion of the pumice. With the pumice sticking to the bottom of the muneca, add a few drops of alcohol (4 to 5) and rub with your finger until the pumice becomes transparent. This "clears" the pumice. NEVER APPLY PUMICE DIRECTLY TO THE SURFACE OF THE INSTRUMENT. Beware of clever gimmicks such as powder puffs and "pounce bags" used to add pumice directly to the surface of the instrument. They are unnecessary and silly.
The pumice is made transparent by wetting it with a few drops of alcohol. |
The grain is filled by moving the pumice-loaded muneca in small circular motions. Direction should be changed often. The grain is best filled when the muneca is moved against the grain direction. Don't move the muncea in long strokes parallel to the grain. |
REVIEW
Now lets review the grain filling procedure . . .
- First, "seal-coat" or "wash-coat" all of the purflings with 3 sessions of shellac, being careful to protect the inlay work from color contamination. Seal the "field" areas similarly.
- While spit coating, fold your shellac cloth often to avoid discoloring the inlay work. Pull the cloth in one direction with a single motion. After spit coating the guitar three times, you can then paint more shellac on the purflings using a soft camel hair painter's brush. Do this if you are having contamination problems.
- Use no shellac or oil during the grain filling process. The spit coats of shellac with the alcohol, combined with pumice, will be all that is necessary to fill the grain.
- Remember to "clear" the pumice. Dab the wet muneca on a little sprinkle of pumice. Add additional alcohol and rub the pumice evenly on the bottom of the muneca to clear the pumice.
- Always load the muneca from the outside with alcohol. Be careful to not add too much alcohol. 10 to 12 drops to a dry muneca and 4 to 5 thereafter should be all that is necessary.
- Using firm pressure, rub the muneca onto the surface using circular motions and change directions often.
- Grain fill only small sections of the guitar at a time. Any excess pumice can be moved to an unfinished area using a little alcohol.
- Inspect your work often and use very little pumice as you work. Do not get impatient and try to hurry. This may result in more work in the long run. A bright lamp at a low angle will help visualize unfilled pores.
Making the muneca
Lets start our project by first making our muneca. There are a number of ways that a muneca can be made but to simplify the task we will explain several ways that we make ours.
A muneca cover made of several layers of wool. |
First, cut three round disks out of a thick wool sock or sweater. Be sure that it is 100% wool. If it contains any synthetics it may not dispense the shellac properly. The first disk should be about 1 & 1/4" in diameter.The second one should be 3/4" in diameter and the third about 1/2" in diameter. Now, stack all three together starting with the largest going down to the smallest. With a needle and thread sew the edge of the large disk to the top of the small disk. Do not pull the edges tight. Sew them just enough to keep them together. Next, cut a 4" x 4" square of t-shirt material and lay it flat on the table. Lay the stack of wool with the large flat side in the middle of the square.
A muneca core made of 18 inches of cotton gauze. |
Grasp the four corners of the t-shirt material and twist all four corners until the encapsulated wad of wool lays firmly between the thumb, index, and forefinger. Another way to make the muneca is to cut a small wad of wool from a wool sock or sweater about 3" x 3" square. Form into tightly in the muneca cover as we did before. Attach a rubber band around the base of the core and really flood it with some 2-pound cut shellac. Let the muneca sit in the open air for several hours. Once most of the alcohol evaporates the core will retain its shape. Cotton is an alternative to using wool for the muneca core. Surgical gauze (from a pharmacy) makes a good core. Cut about 18 inches of gauze and begin by
Before using the muneca, twist it tightly to make it harder. |
folding one end over and over again. Rotate the folded portion after each wrap while attempting to make the core as tight as possible. Ideally, you would like to make a finished core that has a somewhat rounded bottom and about one-half as high as it is in diameter. Once the gauze has been wrapped into the shape and size you want, wrap a cover around it and hold it in place tightly with a rubber band. Flood it with shellac and let it evaporate as in the above example. In both these examples you will probably want to make new covers rather than use the covers with the dried shellac as they will take quite some time to soften. Always put your munecas into a sealed container when you are not using them. Add a few drops of alcohol to the container. This will help prevent the muneca from getting hard. Also take care to change the muneca cover whenever it becomes damaged (often when you use pumice) or stained.
BODY SESSIONS
Assuming that the pumicing and grain filling went well and has been completed, we now begin our French polishing "sessions". We use the term sessions rather than "coats" such as a furniture finisher would use. We will be applying literally hundreds of microscopic layers of shellac to the instrument resulting in one single amalgamated layer of shellac. As you can see, in the case of French polishing, the term "coats" does not apply. During each session we will apply dozens of layers of shellac and will complete as many sessions as it takes to "body" the guitar (which is usually 6 to 8). Before proceeding, you may wish to examine the entire guitar very closely for any defects or unfilled grain that may have been overlooked previously. A little pumice and alcohol will take care of the unfilled grain. Remember, it is never too late to pumice. If the defects can be taken care of by a light sanding, use only 400 grit wet and dry sandpaper with oil as a lubricant. At this stage of finishing, in areas where there are "sink-outs", nicks and dents will tend to show where they previously were not apparent. This is the time to take care of and remedy any trouble spots that are visible. Any sink-outs, pin holes, or nicks can be filled using SuperGlue. First clean the area with naphtha, apply the glue and sand with 400 grit wet or dry sandpaper using oil as a lubricant. Now remove any excess pumice that may be left on the surfaces of the guitar using alcohol and a new muneca cover. The new muneca cover, along with alcohol, will tend to collect excess pumice. Now that we're satisfied with our inspection, lets begin "bodying" the guitar with shellac.
BODYING
Bodying is the process of applying shellac in many thin applications until a sufficient thickness is achieved. The body is sufficient when it can be sanded level with very fine sandpaper without burning-through to wood. Hundreds of passes of the muneca will be required, though individual layers are not the result. All the passes merge into one amorphous "sheet". Downward pressure of the muneca is critical for achieving a good degree of hardness of the final finish. We will be using a full 2-pound cut for the first 6 to 8 (body) sessions. Since we will not be too concerned about how smooth the body sessions go on, our efforts will be to build up the base finish as rapidly as we can. Later we will "level" the body coats to a perfectly smooth surface. Remember that we have already mixed a 2 pound cut of shellac and should be ready to proceed. The object of bodying is to build up enough finish on the instrument to allow it to be sanded level with fine sandpaper.
Glide the muneca onto the surface and move it in circular or oval patterns that overlap |
Lets start by first installing a new muneca cover. As a matter of fact, you should cut a number of 4" x 4" squares of t-shirt material for muneca covers to have on hand as we proceed If at all possible find some well worn and laundered t-shirts. They tend to be softer than new material. Now add about 8 drops of 2 pound cut shellac. To this, add about 6 drops of alcohol. After a while you will be able to accurately estimate the amounts without counting drops. Finally add a drop of olive oil. Just wet the tip of your finger with oil and rub onto the bottom of the muneca. Smack the now loaded muneca against the back of your hand (several times) to distribute the shellac. Why the back of the hand? You will want to have a clean left palm to hold the guitar tightly while you work. The most difficult part of French polishing to master is in knowing when you have the muneca properly loaded. A good gauge is to use a piece of folded typing paper placed next to your work. When you load the muneca, smack against your hand several times and then blot against the paper. If you have added too much mix, the muneca will be too wet and the blot will also appear wet. If the mix is too little, no blot will show. If you have the correct amount, the blot will appear as many individual, separated spots on the paper. Another positive indicator of a properly loaded muneca is the famous "cloud" that is left behind the muneca as it lays on the shellac. This cloud is much like the cloud that your windshield wipers leave when there is oil on the windshield- appearing and disappearing as the wipers work back and forth.
"Pulling-over" the surface using long, straight strokes. Note that the finish is building nicely. Also not the small amount of oil on the surface- indicated by the arrow. |
When the blot test shows that you have the right amount of mix, glide the muneca onto the surface of the guitar, using circular strokes, starting with the back (why the back? It is the easiest surface of the instrument to start with. It is relatively flat and has no obstructions or corners) Watch for the cloud or film of shellac left behind the muneca. Always glide onto and off of the surface of the instrument to prevent the muneca from sticking. NEVER STOP MOVING THE MUNECA WHEN IT IS IN CONTACT WITH THE INSTRUMENT. If you stop the muneca on the surface it will stick and damage the finish where you stop. Press firmly and use circular (or oval) and overlapping strokes as you cover about 13 of the back of the guitar. Move the muneca in patterns that will insure coverage of the entire surface. Be very methodical as you work. Be certain that you are getting even coverage over the area that you are working on.
Always blot the newly charged muneca on paper prior to contacting the instrument. This will help prevent damage due to an overly wet muneca. |
No, this is not the result of consuming too much ethanol during polishing. This represents a method of changing directions without stopping or lifting the muneca. |
The arrows indicate how the fingerboard or other obstruction is dealt with. Overlapping ovals are made that run up against the edge of the fingerboard. |
Spiriting
After the guitar "gases out" for about an hour, you are ready to "spirit off" the guitar. Spiriting is the procedure used to remove the excess oil that has accumulated on top of the guitar's finish.
Spirit the surface using long, straight strokes. Use less pressure when the muneca is wetter and more pressure when it is relatively dry. |
During most French-polishing processes "reading" reflections can be a valuable method of evaluating your progress. |
Review
Now, lets review the bodying procedure . . .
- Load your muneca with alcohol, shellac, and a single drop of oil. If your muneca is new you should wet it with at least 10 drops of alcohol for the first loading. Once the muneca is used, 6 to 8 drops of drops of shellac to five or six drops of alcohol will be sufficient to load the muneca from then on.
- Smack the loaded muneca against the back of your hand to help distribute the shellac/alcohol mix. Use a sheet of typing paper to blot the muneca. A wet blot means too much mixture. No blot at all means it's too dry. A water mark print means that the muneca is correctly loaded.
- Always glide on and off the guitar. Use rotating strokes, never stopping the muneca. Doing so will damage the finish where you stop.
- Be methodical. Mentally divide the guitar surfaces in sections and do each section, one at a time, assuring even coverage. Apply shellac to the surface using circular overlapping strokes followed by long straight strokes pulling over the shellac. Pressure is very, very important. In general, use low pressure when the muneca is wetter and more pressure when the muneca is drier.
- Watch for the telltale cloud behind the muneca! No cloud means that no shellac is going on to the guitar.
- Use a paper towel or dry rag to blot excess moisture from the muneca. A muneca that is too wet will damage the instrument.
- Use only alcohol while stiffing off the surface. The residual shellac in the muneca will assure that no shellac is being removed during stiffing.
- Stiff the guitar in one direction. From the heel to the tail, start from the middle and work to the edges. When stiffing the sides, start at an edge and work to the middle.
- Develop a technique that will allow you to change directions without stopping the muneca. Circular and figure 8 patterns followed by long straight strokes are used by experts.
- Pay close attention to the edges and the corners of the guitar. It is natural to neglect the edges. Always treat the edges as separate surfaces. This will assure that the finish on the edges will not be too thin
- Remember, use the oil sparingly. It is not necessary to add oil each time that you recharge the muneca. Use oil only when the muneca begins to drag or has a tendency to stick
- In most cases, twice over the guitar using circular patterns, once using straight passes, and stiffing between bodying is considered a session. Remember, the muneca is gliding over the surfaces of the guitar many times as you work methodically in an area. In actuality, you have (or should have) covered every square inch of the guitar many times during each session.
- Look over the guitar very carefully and re-pumice areas that may have been missed.
- Spirit off the entire guitar using only alcohol added to the muneca using firm even strokes.
- Continue to body for at least 4 more sessions
Glazing
Glazing is different from that of bodying the guitar by two major distinctions. First, we will use a very thin cut of shellac instead of the 2 pound cut that we have used up until now. Second, we will apply the shellac without using more straight patterns and fewer circular patterns. We will apply the shellac almost exactly the same way as we stiff the guitar. That is, we will start in the middle of the back of the guitar and apply the shellac mixture in a straight line from the heel to the tail. Circular patterns are used less often and are a method to correct problem areas. The object of glazing is simply to fill scratches left by the final leveling (sanding). Lets proceed as follows . . . You can make the thin glazing cut of shellac by simply adding several parts of alcohol to 1 part of shellac that you have been using up until now. Install a clean muneca cover and add a few drops (about 3 or 4 drops) of the 2 pound shellac. Add an equal amount of alcohol to the muneca and a drop of olive oil. Again as always, smack against the back of your hand to distribute the mix. Now, in a straight line press the muneca firmly starting from the heel and go to the tail of the guitar. Remember to glide on and off the guitar.
Repeat this pattern working from the middle to the edges of the guitar always watching for the cloud. Repeat this on the top, sides, and neck of the guitar. If you discover any defects while glazing the guitar use a very fine 1200 grit wet or dry sandpaper to level the area and continue to glaze the guitar. Remember to glaze the corners of the guitar and take extra care around the perimeter. This glazing procedure serves three purposes. First, it tends to smooth any ridging while filling the micro-scratches left from the final leveling. Second, the very thin cut of shellac tends to polish the instrument to a higher gloss while adding additional shellac to the guitar. Third, since more pressure is used, it tends to harden the finish. Many expert French polishers will add additional body coats after the final leveling and then use a liquid abrasive/polishing compound in place of using the glaze coat method that we use. You do, however, run the risk of actually polishing through the finish to the wood. An abrasive such as automotive rubbing compound will remove the very thin shellac finish. We have tried both methods and agree that the glazing method leaves a much richer and deeper finish without the risk of ruining a great deal of work. Once the glazing procedure is completed, inspect the work to locate any dull areas or defects. Lightly sand defects with 1200 grit wet or dry sandpaper and add additional glaze coats to the entire area. Dull areas are probably a result of the finish being too thin or of scratches not fully filled (glazed). If you discover a defect in the side of the guitar, sand and re-glaze the entire side. The same should be done on the top, back, neck and any other area that requires attention. When the final glaze coats are dry (about 4 days) we can now polish out the guitar. Polishing This is the simplest part of French polishing. First, go over the entire instrument with Meguiar's #7 Show Car glaze. Once again, if you discover a thin or dull area, add additional glaze coats. You will need to wait at least two days after any glazing process before you can use the Meguiar's and complete the project.
Having adequate light will greatly help in gauging your progress.
If you discover a slightly dull area or tiny scratch at during the #7 process you can attempt to correct the problem with Meguiar's #9 Swirl Remover. Be careful since this product contains a fine abrasive. The idea is to polish out a defect rather than fill it with more glaze sessions. This will only work if there is enough finish present to allow for abrasive polishing. Keep in mind that many times dull areas are a result of the finish being too thin. Abrasive polishing will only worsen this type of problem. On the other hand- a thin, dull area will need to be re-glazed with more sessions anyway so the abrasive polishing with Meguiar's #9 may be worth a try.
Again, good light is a must. Note the smears of oil on the surface that is being glazed. The Meguiar's #7 will remove this residue easily.
번호 | 제목 | 글쓴이 | 날짜 | 조회 수 |
---|---|---|---|---|
1242 | 어린칭구가 연주할 기타는 얼마나 작아야죠? | 김종표 | 2001.03.02 | 8516 |
1241 | 어린이용 기타아 | 문병준 | 2001.03.02 | 14641 |
1240 | 어린이용 기타 | 마~당발 | 2001.03.03 | 11680 |
1239 | 라미레즈 갖고시퍼라 | 라미레즈팬 | 2001.03.03 | 8943 |
1238 | 베르나베라는 악기가 궁금합니다 | 악기사랑 | 2001.03.06 | 16722 |
1237 | 다현기타의 특징및 제작가는? | illiana | 2001.03.06 | 11782 |
1236 | 몇번본 베르나베. | 수 | 2001.03.06 | 9648 |
1235 | ☞ 라미레즈 갖고시퍼라 | csr | 2001.03.07 | 13163 |
1234 | ☞ Jonathan Hinves는요..(형서기님 설명 좀 더해줘요) | 궁금이 | 2001.03.07 | 13230 |
1233 | Jonathan Hinves 덧붙여.. | 형서기 | 2001.03.08 | 10934 |
1232 | 기타 뒷판이 터지면???? | 으랏차차 | 2001.03.08 | 8727 |
1231 | ☞ 중국은 황사로 너무 건조한가보네요. | 으랏차차 | 2001.03.09 | 9139 |
1230 | ☞ ☞ 중국은 황사로 너무 건조한가보네요.(정정) | 으랏차차 | 2001.03.09 | 14042 |
1229 | Thurman Guitar | 고정석 | 2001.03.09 | 30659 |
1228 | ☞뜨아..울림은 좋을것 같은데 맑지는 않을것 같다... | 명노창 | 2001.03.10 | 8750 |
1227 | 기타 계간지가 있다고 들었는데.. | 윤성규 | 2001.03.13 | 11497 |
1226 | 수님 반갑습니다....그리구요.. | yosip | 2001.03.14 | 9545 |
1225 | 기타를 사랑한다 하면서도 | maria | 2001.03.15 | 9512 |
1224 | 기타 앞판에 쪽물 들이면 이쁘겠다... | 기타랑 | 2001.03.15 | 10670 |
1223 | 저렴한 기타의 꽃단장? 2 | 김현영 | 2001.03.16 | 11276 |
1222 | 수제품기타의 정의는? | 으랏차차 | 2001.03.16 | 9147 |
1221 | 지나가던 녀석입니다.. (-.-) (_._) 꾸벅! | 변태원숭이 | 2001.03.17 | 13281 |
1220 | 직업때문에 연주회 구경 못가는 심정 | 백영업 | 2001.03.17 | 9097 |
1219 | 한국최고의 칠 "황칠" 6 | 일랴나 | 2001.03.17 | 15722 |
1218 | 세락을 능가하는 한국 고유의 "황칠" | 일랴나 | 2001.03.17 | 14432 |
1217 | ☞ ☞ 수제품기타의 정의....개인적인 생각. | 피어리나 | 2001.03.17 | 11434 |
1216 | ☞ 8현사랑. | 피어리나 | 2001.03.17 | 11848 |
1215 | 셸락칠의 단점극복에 기대하며... | 수 | 2001.03.18 | 9231 |
1214 | 나의 베르나베는 이렇게 1 | LAEL | 2001.03.18 | 9923 |
1213 | ☞ ☞ 바이올린에는 사운드포스트라는 게 있다던데..... | 피어리나 | 2001.03.18 | 13134 |
1212 | ☞ 베르나베 연습용은 하청... | ^_^ | 2001.03.19 | 10626 |
1211 | 이병우의 기타 컬렉션.. | ganesha | 2001.03.22 | 13272 |
1210 | photo of my guitar-1 | UraCHaCha | 2001.03.25 | 10498 |
1209 | ☞ photo of my guitar-1 | 으랏차차 | 2001.03.26 | 9457 |
1208 | ☞ 내기타에 문제들..웅수님도 보셔요~ ^^ | 길손입니다. | 2001.03.26 | 9707 |
1207 | ☞ ☞ 댐핏대용으로 쓸 수 있는것,,, | 명노창 | 2001.03.26 | 8855 |
1206 | ☞ ☞ ☞ 앙...으랏차차님 이구나..... | 명노창 | 2001.03.26 | 8903 |
1205 | 자잘한 상처들은 좋아요. | 수 | 2001.03.27 | 13857 |
1204 | ☞ ☞ ☞ ☞ 중국 사업 | 으랏차차 | 2001.03.27 | 10213 |
1203 | 기타 추천 바랍니다. 1 | 박재만 | 2001.03.28 | 7760 |
1202 | ☞ 기타 추천 | 수 | 2001.03.28 | 8931 |
1201 | 몬테로 부쉐모델 쓰시는 분 안계시나요? | 간절한 | 2001.03.29 | 7681 |
1200 | 안녕하세요 ^^ 제 기타입니다 | 나이스드림 | 2001.03.29 | 10269 |
1199 | [초보]질문있습니다 | 기타치고시퍼 | 2001.03.29 | 8655 |
1198 | ☞ 몬테로 부쉐모델 | 명노창 | 2001.03.29 | 9913 |
1197 | ☞ ☞ 정말 스페인에 가면 바로 살수..... | 간절한 | 2001.03.29 | 8733 |
1196 | 최근에 기타제작 콩쿨이 있었다는데.. | 방문객 | 2001.03.31 | 8739 |
1195 | 국산기타와 외제기타 | 으랏차차 | 2001.03.31 | 9500 |
1194 | 기타제작콩쿨은 아무도 .. | 방문객 | 2001.04.01 | 9504 |
1193 | ☞ ☞ ☞기타 사느라 장가 포기를 포기.... | 간절한 | 2001.04.01 | 10074 |
1192 | 30분후 기타 소리가 조아지는데... | 새내기 | 2001.04.02 | 9786 |
1191 | 정말 놀랬습니다 | 기타지존 | 2001.04.03 | 9559 |
1190 | 수제품을 구입하려는데... | 세고비아 | 2001.04.03 | 10076 |
1189 | 세고비아의 기타. | 수 | 2001.04.05 | 15721 |
1188 | 안토니오 마린 몬테로에 관한 나의 견해 | 길벗맨 | 2001.04.05 | 11895 |
1187 | ☞ 가오리가 쓰는 기타가? | 왕초보 | 2001.04.05 | 10634 |
1186 | 두분 의견 감사드립니다. | 길벗맨 | 2001.04.06 | 11148 |
1185 | 나의 기타 | 수집걸 | 2001.04.06 | 9434 |
1184 | 군대에서 있었던 추억담~ 기타이야기^^;; | 정성민 | 2001.04.06 | 9671 |
1183 | ☞ 군대에서 있었던 추억담~ 기타이야기^^;; | 딴따라~! | 2001.04.06 | 10589 |
1182 | 험프리, 밀레니움 모델, 경사진 앞판 디자인. | 서정실 | 2001.04.07 | 10353 |
1181 | 가격대별 기타 사진(headstock, rosette, label) | 고정석 | 2001.04.08 | 11383 |
1180 | 질문요. 1 | 방문객 2 | 2001.04.08 | 8287 |
1179 | 유명악기에 대한 평이 엇갈리는건... 1 | 수 | 2001.04.09 | 8434 |
1178 | 무대용과 녹음용 악기의 차이?? 4 | 일랴나 | 2001.04.09 | 11246 |
1177 | ☞ Ruck 애기가 나오길래. 2 | 서정실 | 2001.04.09 | 10727 |
1176 | 카즈오 사또 시몬(?)에 대해 알고싶습니다. 5 | 청년 | 2001.04.10 | 7357 |
1175 | 30분전에 준비된 소리가... | 새내기 | 2001.04.10 | 9479 |
1174 | 가즈오 사또 3 | 강명구 | 2001.04.12 | 11544 |
1173 | 아름다운 CF 한편... | 木香 | 2001.04.13 | 12787 |
1172 | 연주회합니다~ 3 | 정호중 | 2001.04.14 | 9763 |
1171 | 김희주양 클래식기타독주회(현 서울음대2년재학중) 1 | guitar~ | 2001.04.16 | 9684 |
1170 | 50호정도의 기타를 구입하려는데 조언을 17 | 오원근 | 2001.04.18 | 9823 |
1169 | 스프러스와 시더 3 | 무아 | 2001.04.19 | 10931 |
1168 | 고노와 사쿠라이의 가격 2 | 기타좋아 | 2001.04.19 | 13149 |
1167 | 로제트는 어떻게 만드나요? 3 | 으랏차차 | 2001.04.20 | 11184 |
1166 | 네크의 두께.. 2 | 으랏차차 | 2001.04.20 | 11214 |
1165 | 멋뜨러진 기타가 좋아요!!!!!!!!!!!!!!!!!!!!!!근데 돈이 엄따 2 | 기타살앙 | 2001.04.21 | 9520 |
1164 | 기타케이스...skb 2 | 목향. | 2001.04.22 | 11638 |
1163 | 기타 머리 11 | Lacote | 2001.04.26 | 10541 |
1162 | 음반 표지 소개. | 눈물반짝 | 2001.04.30 | 9875 |
1161 | 해드가 신기하게 생겨서... 4 | 목향 | 2001.04.30 | 11063 |
1160 | 엄씨 가문의 기타에 관한 냉철한 평을 부탁드립니다. 15 | 남경민 | 2001.05.02 | 11118 |
1159 | 제 생각엔요.. | 형서기 | 2001.05.03 | 16954 |
1158 | ☞ 써봤습니당. 엄씨가문의 기타를!!!보았습니당. 엄씨가문의 기타를!!! | 간절한 | 2001.05.03 | 10969 |
1157 | ☞ 현재 사용중입니다. 평이라...글쎄요.. 4 | 꼬 | 2001.05.03 | 13434 |
1156 | 기타도료에 관한 사소한 질문입니당-특히 수님께 여쭙니다용??? 3 | 간절한 | 2001.05.05 | 8247 |
1155 | 수님~. 기타 부품에 관해서~ 2 | 김현영 | 2001.05.05 | 9258 |
1154 | 국산 악기에 관하여. | 형서기 | 2001.05.06 | 15164 |
1153 | ☞ 형석님 글 정말 잘 읽었습니다. | 꼬 | 2001.05.06 | 13507 |
1152 | 기타내부에 칠을 하면... | 수 | 2001.05.06 | 15237 |
1151 | 아유...그런거 지천이야요... | 수 | 2001.05.06 | 8052 |
1150 | 기타 고르는데요...잘 모르겠어여...ㅠㅠ 3 | 민 | 2001.05.06 | 10993 |
1149 | 하현주를 낮추면??? 2 | 간절한 | 2001.05.07 | 11506 |
1148 | ☞ 하현주를 낮추면??? ... 글쎄요...??? | pepe | 2001.05.07 | 9178 |
1147 | ☞ 기타의 수명이 짧다는 것이 근거없다는 어느 가설 | 셰인 | 2001.05.08 | 14611 |
1146 | 할 줄 아는 것이 정말 없고낭....쩝.... 1 | 간절한 | 2001.05.08 | 10785 |
1145 | 존 윌리암스가 기타를 스몰맨으로 바꾼이유. 11 | 길벗맨 | 2001.05.08 | 11964 |
1144 | ☞ t-brace. 5 | 서정실 | 2001.05.09 | 11477 |
1143 | Dieter Hopf 8 | 박카스 | 2001.05.09 | 13092 |
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