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PostPosted: Fri Jan 15, 2010 4:08 pm 
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Old Growth Brazilian
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After many starts a restarts i finall wrote it out complete. Lance if you could plaease replace the original thread with this one if you had rather not I titled this one as "revisited as a modifier


French Polishing with Michael Payne

Introduction

First a little about my self before we get started; I grew up in my grandparents 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 to some about what make for a good hard finish. Never the less my technique is proven to provide a smooth, hard durable finish worthy of a fine instrument or piece of furnisher.

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 applying one layer over the next. In French polishing we will build one continuous amalgamated film in a series of processes preformed in a series of sessions.

Not counting the pore filling process; for which there are a myriad of media and techniques that are acceptable to French polishing; the three basic process to French polishing are known as Bodying, Spiriting-Off and Glazing. Here is a brief explanation of each of these processes.

Bodying
Applying shellac via a muneca or two piece pad in overlapping figure eight or circular motion; this process is much like applying past car wax to a car or paste shoe polish to a shoe. This process builds the majority of the films thickness but does not provide the finish sheen

Spiriting-Off
This process is done with a moderately high alcohol load with very little to no added shellac other that the residual shellac already in the inner muneca. This process is a glide on glide off straight stroke buffing like process done to melt down and level out riding and high spots. And to remove lube oil left by bodying or glazing

Glazing
This is the application of 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 a 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 or 6 oz of 100% pure Walnut oil or Extra Virgin Olive oil

Eight to ten 4” x 4” well worn non-dyed Muslin or linen squares (Outer muneca or outer pad)

A couple feet of non-dyed 100% wool roving. (Inner muneca or pad)

Three 2 or 4 oz plastic bottles with caps (bulk shellac and oil storage)

Three eye dropper bottle with eye dropper (one for 2# shellac, one for 1# shellac and one for the lube oil. used t store shellac and oil for loading the muneca)

Small natural bristle artist brush

Available supply of 8.5 x 11 printer paper

A good med high intensity work lamp

A lint free work pad like a well worn folded linen sheet

Several pair of nitril gloves

Last but not least; A good bit of patients 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 or Liberon’s Pale French polish pre mix because they are quite good off the shelf French polish shellac mixes. I like the slight amber tint that the Zinsser Seal Coat provides. 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. If I want a less tinted appearance then the Liberon’s Pale French polish would be my choice. both come as a 2# cut straight from the can. I cut that with 25% per volume with to achieve a near 1# cut. I make up 2 oz at a time and store in the plastic 2 oz squirt bottles I mentioned in the supply list.

Preparation of the Muneca.
Make up at leas 6-8 outer pads 4” x 4” square from well used white muslin or linen for the outer cover. You want this material clean and well worn. If new wash at least 10 times before using to remove any loose fiber. T-shirt material is often suggested and will work well but I find it causes unneeded ridging during bodying due to its 3D stretchable weave.

I prep my inner muneca a day in advance. These are made from 100% non-dyed wool roving and enough to make a tight golf ball when dry. To prepare I first set the ball of wool roving on a piece of wax paper in a bowl and saturate them with 2# cut of shellac. I then allow it to stay in the open air bowl for about 2 hours. At this point I put on nitril gloves and roll the ball in the palm of my hand over the bowl till no shellac drips from it. It should be about the size of a ping pong ball or slightly smaller at this point Then place the ball into a zip lock bag with the seal half open over night or until the ball is the consistency of soft taffy then seal the bag air tight. At this point the inner muneca is ready to use. It is important tht the inner muneca be at this viscosity for the muneca to work properly. If the inner muneca is too wet it will not form the proper wicking channels between the inner and outer muneca. In fact if the inner of outer muneca are too wet they may remove shellac rather than apply it.

Once the 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. Keeping 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 muneca.

A little note of interest the word muneca is Italian for rag doll in reference to the pad having the appearance of rag dolls 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 are any colored purfling that need sealed to protect from bleeding woods this should be done first with 1# cut of shellac and a fine artist brush before the seal or spit coat is applied. This way if during the application of the seal or spit coat; any bleed over occurs it can be scraped off with a razor blade or small cabinet scraper then resealed with shellac. I seal or spit coat in this order; purfling, top and then back and sides.

The initial spit coat is applied much like 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 the tap one time on a sheet of white printer paper. The forces the alcohol and shellac into the inner pad stating the wicking process of the residual shellac in the inner pad. Start on the top and cover evenly the top 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 working. If it does it will stick causing a lumpy buildup. After the top do the back, one side then the other allow about 10 min of cure time before moving on to another surface.

This spit or seal coat is the foundation of the future body sessions. It went on wetter than the body session will and is done so that the dryer first body session have 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 boding is and is not.
Bodying is the application of the residual shellac contained in the inner muneca transferred on to the work surface by means of melting apportion of this residual shellac with a fresh load of shellac and alcohol to the outer pad that is then taped on a piece of paper causing the newly loaded shellac and alcohol to be forced into the inner muneca partially melting the residual shellac of the inner muneca thereby creating a wicking channel for the melted residual shellac to flow from the inner muneca through the outer muneca and on to the work surface.

Bodying is not the application of a wet fresh load of shellac loaded on to the outer muneca and then painted or ragged over the surface. In fact that is exactly what we do not want.

The reason for not wanting to apply the shellac as a wet film has several reasons. First is that a wet media migrates. It wants to flow until it thickens enough to overcome the flow. This means that you would likely end up with thicker film at the ends of the flow than at the center. Second is the fact it is harder to control the application thickness of a media that is low viscosity as apposed to a higher viscosity.

Tell-tale signs the muneca is properly loaded:
There are two key tell-tale signs if one you have the muneca properly loaded and if the wicking is happening.

The fist 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 till the stain (referred to as “report” from here on in this tutorial) is spotty not solid. This is the first tell-tale sign. It ells you the muneca is loaded and prepped for boding.


The second tell-tale sign of a properly loaded muneca is displayed during the bodying process. This sign is the vapor trail of alcohol appearing and rapidly disappearing behind the muneca as you body. For an example of this next tell-tale sign; take your safety glasses off and breathe on them. Notice the water vapor from your breath appear and disappear quickly on the lens. This is water vapor flashing off a dry surface. As we body we want to see the alcohol vapor of the new load doing the same thing as the muneca moves along the work surface. Seeing or not seeing this sign tells you really several important things. One; that the wicking action is of is not happening. Two; it tells you if your load has too much or little shellac or alcohol. Be aware 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 ¼” to ½” or a little more behind the muneca as you body.

If there is no vapor trail but there is a thick wet trail behind the muneca that does not disappear quickly as the muneca moves this tell you that you have loaded the muneca with too much fresh shellac.

If you see a thin wet trail that does disappears fairly quick but not as nearly as quickly as I described above; this tells you have loaded too much alcohol. This will lead to a messy pushing of previously applied shellac forward of the path of the muneca and thereby a very unlevel surface.

If there is no vapor trail and no wet surface behind the muneca then you have too little alcohol in the load. This will likely lead to the muneca sticking as you body.

Do not confuse wet shellac as a vapor trail. Once again the vapor tail will appear and disappear just like the fog you see when you breathe your safety glasses.

Before we go into how to do the body process I would like to discuss first how the inner muneca works for us when boding. Recalling the inner muneca prep that I gave earlier, understanding why and how the inner muneca works will greatly aid you in noticing how well your body session is going and help you reason out many difficulties you may face when boding.

Think of the inner muneca as a reservoir of shellac. It is this shellac that is to be applied to the surface during both bodying and later glazing processes. Each new load to the muneca you add during boding does two things. First and foremost a new load melts residual shellac in the inner muneca and primes the muneca to allow the meted residual shellac to wick through the outer pad and on to the surface. The shellac that is wicked is of higher viscosity than liquid 2# cut straight from the bottle because it is partially set up or gelled.

During bodying we want the shellac being applied to the surface to be pretty much the constancy of a soft past car wax. That is somewhat of an exaggeration because shellac has a tack to it that past car wax does not. But it is a good mental conception of how applied shellac should be thought of during the bodying process.

Waxing a car is also a good description of the application technique. When you apply car wax you apply it in overlapping figure eights so that you spread it evenly over the surface. The same is true for the application of shellac during the bodying process Keep your circles or figure eights tight and overlapping by about half the muneca diameter.

I find it best to body from the edge at one end and work towards the opposing end migrating one hale the muneca diameter until you reach the centerline of the surface then do the same for the other side. You can if you wish work from the centerline of the surface towards an edge if that is your preference. But in either case work the surface as two halves. This intrinsically leads to building a more consistently level surface that going willy-nilly all over the place. Also pay close attention to the edges. This is where you are most likely to miss in your coverage. Beware that dependent on the size of the surface you are bodying; you will likely have to reload the muneca several times in one session. As soon as you start to feel the resistance between the muneca and the previously applied shellac build up to the point you think the muneca may stick or if you stop seeing the vapor trail behind the muneca it is time to reload.

After each body session; I recommend you allow the surface to set for 10 minutes or till dry to the touch. After the surface has dried to the touch I also recommend a spiriting off session and allow to dry to the touch again before moving on to the next body session. This provides several beneficial outcomes. First and foremost it melts over any ridging left behind during the previous bodying session which if done after every body session will greatly aid in building a level film as you body. Also spiriting-off will remove the oil used to reduce the surface tension from the previous body session. For info on how to spirit-off see the “Spiriting-Off” section.

You will in most cases wan to build a film thickness between 3-5mils thick. Normally this is done in six to eight body sessions.

Spiriting-Off:
Spiriting-off is the process of melting down ridging and high spots and or wiping off oil from the surface of bodied or glazed surface. Spiriting-off uses the same muneca used in bodying or glazing. The load how ever is much different. When spiriting-off your load will be mainly alcohol with only one drop of oil added to break the surface tension. Because the load is mainly alcohol the residual shellac that will wick through the muneca will be of a far lighter viscosity in fact the viscosity is so light that very little shellac will be transferred. Because the new load will have much more solvent than shellac the way the stroke happens must be altered from the previous boding stroke. The Spiriting stroke is a glide on glide off stoke that is quick and slightly firm If the stroke is slow and deliberate we would end up melting too much of the previously applied shellac and end up dragging a groove in the film. Instead we just want to melt the shellac tht is higher than the base thickness and wipe of the oil.

The stroke starts by gliding on to one end of the surface and end by gliding off the opposite end in a non stop quick motion each pass of a given spiriting-off session should start at one given end and end at the other each pass should over lap by half the muneca diameter. Never repeat a spiriting-off pass in the same place twice in a given spiriting-off session. This will lead to over melt of the film. Always work for the middle of the surface and work your way towards the edges. This avoids over melting the edges which would lead to a excessively thin film at the edges.

You can alternate which end to start at; every other spiriting-off session to insure building a level film. Here again, depending on the size of the surface you will likely have to reload the muneca several time to complete a session. I always wipe the muneca with just a small drop of oil at each new load. this is only to prevent the muneca from sticking as it first touches the dry to the touch film from the previous body and or glazing session.

Most other French polishing tutorials recommend spiriting-off every third body session. Those same tutorials lead you through an abrasive sand paper film leveling process between the bodying and glazing process to insure a level surface. I do not teach abrasive leveling, though it is and acceptable process. I teach building a level film as you build the film thickness. Regular spiriting-off sessions is key to building a level film as you go and will eliminate having to wait for the film to cure out then sanding to level.

Glazing:
Glazing is the process that refines the film and polishes (actually burnishes) it to a desired sheen. Glazing is much like spiriting-off with the exception of additional 1# shellac added to each load. Using thee same muneca as before but with a lighter cut of shellac work from one end towards the other in a straight line with the grain is preferred. Work from the centerline of the surface and work towards one edge then again from the centerline towards the other edge. The stroke for glazing needs to be quick and deliberate.

The typical load for glazing is 3-4 drops of 1# shellac, 3-4 drops of alcohol and 2 drops of oil. Glazing is slightly wetter process than bodying. But not by a lot just a little.

The intent of glazing is to refine and polish the surface of the film. Work with a work lamp mounted at the opposite end of your workstation than you are standing at. Direct the work lamp so that you can see the reflection of the lamps bulb on the surface you are glazing. As you glaze you will notice the reflection of the work lamps bulb slowly come into focus. The more detailed the focus the higher the state of the sheen. You need to move the work around to see the reflection at all location on the surface. The clarity of the light bulb image on the surface will be your key indicator as to how far along in the glazing process you are at and any given location. The idea is to bring all areas to the same sheen. You can pay more attention if need to troublesome areas if needed.

When I glaze I like to spirit-off after every other session for the first 4 sessions. Then eliminate spiriting-off the further along I get. To continue to spirit-off beyond the first few session can lead to dulling of the polishing you have accomplished. Keeping in mind that you are adding some oil at each load up there will be a build up of oil on the surface of the film after you stop spiriting off. This is a good thing. The oil will always rise to the surface and will aid in the burnishing of the film to a high gloss or sheen you desire.

Once you have reached the desired sheen everywhere take a lint free cloth and wipe off the remaining oil. allow the surface to harden for 24 hours and wipe with a lint free cloth lightly dampened with alcohol to remove any oil that is remaining and double check the reflection of the work lamp on the surface to confirm desired sheen.

After a week of setting up you can compound polish or machine buff if desired but the truth is you can get to as high of sheen as you may desire by glazing more.

At this point you have completed my traditional French polish process. You now have a very durable finish that should last a life time. Now this is a shellac finish. It will scratch. It is susceptible to solvents degradation; alcohol based solvents in particular. If by chance an alcohol accident or scratches happen; you can always repair the finish by following the process described above.

Michael Payne


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PostPosted: Fri Jan 15, 2010 5:39 pm 
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Koa
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bliss
Perfect timing. I started looking at this before the holidays wanting to switch to FP. I was bummed you didn't finish it and said you didn't have the time.
Thanks much.


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PostPosted: Fri Jan 15, 2010 5:59 pm 
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Old Growth Brazilian Rosewood
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Excellent Michael - thanks for ALL that you do my friend!!!!

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PostPosted: Mon Feb 01, 2010 2:48 pm 
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Hi Michael,
First off thanks for the great information, your attention to detail is much appreciated. From the begining of this build I had planned to FP and the timing and insight was impecable. I am currently in the process of FPing my first steel string and have come across some things I am hoping you could clarify.

I have prepped the menuca pad as you have described (finding undyed wool roving was something of a challenge, it was hard to even somebody who knew what wool roving was), but am wondering if my inner menuca is properly saturated. With the first attempt, which I have used to apply the spit coat, 1 bodying session, and spiriting off session, and I am starting to think the pad is too dry. During prepping, after allowing to ball to sit open to air for 2 hours, I then rolled and squeezed out all the shellac, then followed the rest of your directions. Even as I started, I never really got the feeling of the pad feeling like the consistency of soft taffy. So....when you roll the ball in hand after 2 hours open to air, was alot of pressure applied to squeeze out a majority of the shellac, or does the ball still have a heavy and saturated feeling to it. I saturated another ball yesterday, applied alot less pressure when rolling, so that I definetly knew the pad was wet and saturated, then let it sit in an open bag overnight, but at this point it seems like it would be too wet and as you mentioned, using it would only wipe off shellac.

So, in writing this I have discovered how difficult it is to accurately describe this very tactile operation. In term of weight, would you say the inner menuca pad is about 1/2, 1/3, etc. of the original completely saturated weight?
Thanks in advance for the advice,

AJ


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PostPosted: Mon Feb 01, 2010 3:03 pm 
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Koa
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Nice to have this all in one spot, Michael.

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PostPosted: Mon Feb 01, 2010 3:07 pm 
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Old Growth Brazilian
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I don't use much pressure at all I just roll it between my two palms till it stops dripping. tha tis key the inner muneca should be full to its capasity to retain shellac.

In regards to bodying too dry most body too wet but if you have pressed out all the shellac out of the inner muneca leaving only that which is attached to the fiber then you are rementing and wicking very little at first. It will get better as you load and reload the muneca because you will eventually build up enough residual in the inner pad.

Now on the "you think you are working too dry" issue. If you are laying a film down then you are not working too dry. if you are constanly sticking and there is no a consistant transfer then maybe so.


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PostPosted: Mon Feb 01, 2010 5:17 pm 
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Brazilian Rosewood
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Nice...thanks, Michael. Of all the methods available, most of yours seems to work best for me.

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PostPosted: Mon Feb 01, 2010 5:37 pm 
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Old Growth Brazilian
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JJ Donohue wrote:
Nice...thanks, Michael. Of all the methods available, most of yours seems to work best for me.
Glad to here it
[:Y:]


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PostPosted: Wed Feb 03, 2010 4:22 pm 
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Cocobolo
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* Print it
* Laminate it
* Post on shop wall

[:Y:]

I'll be French Polishing my first guitar and this is exactly what I needed.

maybe it's worth sticking to the top?


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PostPosted: Tue Mar 09, 2010 11:48 am 
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Cocobolo
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Michael,
Thanks for all yur work in putting this together, yu have made it more understandable for me.
But guess what I still have questions.
1) what should the surface look like after each session of spit - bodying - spirit off?
I have had about 4 sessions & see a surface that has the curve of the figure 8's showing up
2) is it OK to do the figure 8's going along the grain once & across the grain on another session?
3) I know you don't want us to think in terms of 'coats' but in the bodying section I interpret your description as, doing the the figure 8s once over the entire surface. And that, is a session?
thanks
Mike McNerney

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PostPosted: Tue Mar 09, 2010 8:12 pm 
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Michael,

I've been pretty much following your instructions, and bodying hasn't been much of a problem. But if French Polishing a soundboard with the bridge already mounted, or around a neck heel, I have problems with spiriting off and glazing. Around the bridge and the sides of the heel, the only way I can see to get a proper "glide on, glide off ", is to go perpendicular to the grain direction. Is this the way to do it?

Thanks for this and all the other great advice you give,

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PostPosted: Wed Mar 10, 2010 9:33 am 
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Old Growth Brazilian
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1) what should the surface look like after each session of spit - bodying - spirit off?
I have had about 4 sessions & see a surface that has the curve of the figure 8's showing up.


Well if you are spiriting off after each body session the circular marks should be melted flat spiriting is a high alcohol almost no added shellac firm quick non stop pass glide on one end and gliding off the other. This high alcohol load is intended to melt the ridging and sooth the previous body session to flat. You need to over lap each spirit-off pass by 1/4 to 1/2 the muneca width. Start in the middle of the body and work to an edge. Then start in the middle and work to the other edge



2) is it OK to do the figure 8's going along the grain once & across the grain on another session?


It does not mater as the spirting off seession that will follow each body session will melt the ridging.

3) I know you don't want us to think in terms of 'coats' but in the bodying section I interpret your description as, doing the the figure 8s once over the entire surface. And that, is a session?

Correct that is one Body Session. it should be followed by a Spiriting-off session. then when you get to glazing once over is one sessions so forth and so on.

The reason I do not want you to think of coats is because the term coats implies applying one coat over a previous coat. In French polishing wile done one session after another we are not applying a coat over a previous coat. we are melting new shellac into previously applied shellac making one continuous film.

I suspect your swirl marks still showing is due to too little alcohol in your spirit off load and a lack of firmness in the spirit off passes. When I say firm I do not mean hard but I do mean a constant moderate force.


Last edited by Michael Dale Payne on Wed Mar 10, 2010 9:45 am, edited 2 times in total.

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PostPosted: Wed Mar 10, 2010 9:36 am 
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Old Growth Brazilian
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gozierdt wrote:
Michael,

I've been pretty much following your instructions, and bodying hasn't been much of a problem. But if French Polishing a soundboard with the bridge already mounted, or around a neck heel, I have problems with spiriting off and glazing. Around the bridge and the sides of the heel, the only way I can see to get a proper "glide on, glide off ", is to go perpendicular to the grain direction. Is this the way to do it?

Thanks for this and all the other great advice you give,


That is fine and will get the job done. I prefere and teach to spirit- off, glase and polish with the grain but if you build the guitar with the bridge and neck on you simply cant do that every where.


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PostPosted: Wed Mar 10, 2010 9:41 am 
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Old Growth Brazilian
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Guys don't forget!!!!! May 13-16 at Red Rock Community College in Denver I will be teaching my French polishing methods. If interested in attending get in touch with Robbie O’Brian. I gar-on-tee a good time and you might just learn soothing too ;)


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PostPosted: Wed Mar 10, 2010 10:33 am 
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Cocobolo
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Hi Michael,
Thanks a lot, that helps. I wish i could make it to the FP course & maybe someday but I'm already traveling too much this year.
Mike McNerney

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PostPosted: Wed Mar 10, 2010 2:14 pm 
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Brazilian Rosewood
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Michael-
Thanks for all this info on FP.

I still find FP a 'struggle' - sometimes it seems to 'work' sometimes not so well...
Troubleshooting is a real puzzle for me. [uncle]
Some more material for your FAQ file:
1) How do you know it's time to change the muneca cover?
2) I seem to get a lot of shellac buildup at the edges of the muneca -like a ring around the center. Then I start getting scratch-like marks in the finish which don't disappear easily with the spiriting off step.
3) I get a lot of swirl marks when I am laying down finish- I'm not sure if this is normal or a sign that the pad is 'too wet' and picking up shellac from the surface.
4) I don't 'get' the idea about putting alcohol on the pad every time I put shellac on. Why not just use a more dilute cut of shellac? I thought the idea was to keep the pad 'dry' and when I add alcohol it seems too wet, so I end up wringing out the excess in a paper towel, or dabbing it on the back of my (left, gloved) hand or on the white paper nearby.
5) How long should the guitar 'rest' between work sessions? If you are trying to build a finish quickly, can you just keep 'working around' the guitar- top, then side , then back, then side, etc....?
6) What temperature should the work room be? I seem to have more problems when it is cooler, so I've taken to keeping a heater/fan going when I FP.

Thanks again
Cheers
John


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PostPosted: Wed Mar 10, 2010 2:41 pm 
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Old Growth Brazilian
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1) How do you know it's time to change the muneca cover?

Before the shellac starts to crust on the outer cover. when you notice it appears grungy, when you start to see loose fibers.

2) I seem to get a lot of shellac buildup at the edges of the muneca -like a ring around the center. Then I start getting scratch-like marks in the finish which don't disappear easily with the spiriting off step.

Over used outer pad. change sooner, store in a air tight dust free container as soon as you put it down. Most contaminations happen when you set the muneca on the bench

3) I get a lot of swirl marks when I am laying down finish- I'm not sure if this is normal or a sign that the pad is 'too wet' and picking up shellac from the surface.

Scratched in swirl marks are form crusty shellac on the outer pad or dust particals traped in the outer pad. Raised swirl marks are left by the weve of the fabric of the outer pad. Tee shirt material is the worst about this but these are melted over with proper spiriting-off.

4) I don't 'get' the idea about putting alcohol on the pad every time I put shellac on. Why not just use a more dilute cut of shellac? I thought the idea was to keep the pad 'dry' and when I add alcohol it seems too wet, so I end up wringing out the excess in a paper towel, or dabbing it on the back of my (left, gloved) hand or on the white paper nearby.

keep in mind that when we apply a new load, that it is not the shelllac that is being laid down when we body. the new load does two things. It keep the wicking from the inner pad to the outer pad primed and partially melts the residual shellac in the inner pad. But to a degree your are right we are just adding a thiner cut when we load. basicly we are adding a 1/2# cut to keep th wicking happening. You could keep a 1/2# cut handy for load up if you wished but most of us make up a 1# cut for spit coats and glazing and a 2# for boding. Keeping an eye droper bottle of alcohol hand just allows us to adjust the cut as we add a new load. When it is very dry rh and hot we need more alcohol and when it is moderat RH and cool we need less so adjuting the ratio of the load on the fly is simpler when added seperatly.

Every time you load you should be tapping teh muneca to push the new load into the inner pad. If you tap on white paper untill you see a spotted dot rather than a solid dot you are at the right point to start boding. not too dry not too wet. if the shellac looks wet as it is being laid down then your are to wet. if it looks like you are spreading a soft paste wax then you are just right


5) How long should the guitar 'rest' between work sessions? If you are trying to build a finish quickly, can you just keep 'working around' the guitar- top, then side , then back, then side, etc....?

After a body session you should be "to the touch dry" before you spirit-off and "to the touch dry" before you start boding again.

6) What temperature should the work room be? I seem to have more problems when it is cooler, so I've taken to keeping a heater/fan going when I FP.

Within 50-90f is fine. but like I said you adjust your load ratios based on how the shellac is reacting. Dry cold conditions will mean a tad more alcohol per load, Dry Warm will meand even more alcohol because the shellac set faster. Wet Cold means less alcohol. It is very hard for me to give exacts ratios for a given condition or series of conditions. If you follow the ratios I have in the tutorial al will work just fine almost regardless. but as you become more skilled you will notice smalll differances that will suit you individually. but for now just stay close to the ratios given. but pay attention to how the shellac is working and attempt smal ratio changes as needed.


Last edited by Michael Dale Payne on Wed Mar 10, 2010 3:01 pm, edited 2 times in total.

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PostPosted: Wed Mar 10, 2010 2:59 pm 
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Thanks, Michael!!
Incredibly quick response - and complete as well.
If I lived closer, I'd sign up for that course!
I did find the pad needed changing more often when I was using T-shirt material. I went back to some very fine, thin Indian cotton and the problem was less severe. I also am switching to a new cover more often. The whole idea of one pad, many covers was a new one for me.
I do store the pad in a jar (with some other pads and spare covers, with everything 'damp' with alcohol). It is amazing to me that overnight storage can change the muneca quite a bit- the shellac buildup on the cover seems to migrate away. There's a lot going on there. (I still change the cover, now.)

Cheers
John


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PostPosted: Wed Jun 09, 2010 9:26 pm 
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Michael this thread has become my constant go-to resource as I've been working on finish. Thanks soooo much.

What happens after you are done? We are all eager to just string it up. but should I wait, say, about a month before I glue on bridge and neck and then do setup? Or will I be ok if I do this a week after glazing and just try to be very careful with it?

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PostPosted: Thu Jun 10, 2010 1:11 pm 
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Hi Michael,

I am also interested in your answer to the previous message.

Thanks,
Max

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PostPosted: Tue Aug 10, 2010 1:21 pm 
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I usually string mine up within a couple of days. I'm careful, and use a cardboard bib when stringing up, but I have seen no disadvantage to doing it. I am careful with the guitar for the first week or so. I know it's still soft, but it does not seem to be excessively so.

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PostPosted: Tue Aug 10, 2010 1:42 pm 
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enalnitram wrote:
.... but should I wait, say, about a month before I glue on bridge and neck and then do setup? Or will I be ok if I do this a week after glazing and just try to be very careful with it?

I think you'd be fine with regular clamping if you are careful.

I learned something about French Polish and vacuum clamping a few months ago.
If your FP is 'fresh' (and especially if you have perhaps used a bit too much oil in your FP through inexperience :? ) be careful about using a vacuum jig to glue on your bridge.
In my case, the vacuum pulled enough air through the top, or pulled 'something' out of the FP, to turn the surface around the bridge into something resembling 180 grit sandpaper.

It took a bit of work with the muneca to re-amalgamate the surface and touch up the FP.

Cheers
John


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PostPosted: Tue Aug 10, 2010 1:44 pm 
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I sure miss our friend Michael...

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PostPosted: Tue Aug 10, 2010 9:49 pm 
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Thanks guys. I waited a few weeks and it went ok. The thing about too much oil is a good tip. But I already learned about that, on my own, too. Oh, and, also, about leaving oil on the surface too long. As well as many other things! 3 months later, and it's starting to look like a finished guitar.

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PostPosted: Wed Aug 11, 2010 7:52 am 
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Hesh wrote:
I sure miss our friend Michael...


What do you mean ?


I saved this page to PDF as well - I can't wait to get to the final stages !

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