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I guess it is not in the stars for me to achieve a decent finish with shellac. After weeks of frustrations, I 've decided to see if nitro is the right path for me.

I have approx. 20 plus body coats, (not including what I've sanded off and re-applied!!) on the guitar. Will I need to remove most of them to use nitro at this point? Can I just spray over what I've got?

Grain filling was done with z-poxy and then the FP was applied.

I really do like the look of FP,.......pity.

Did you use any oil(s)

that will be the deciding factor!

Mike

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Mike Collins

Krugerr,

Hi,

I am very experienced in French polishing. My self and Colin both have over 30 years of French polish experience each. One of the two of us can and are more than willing to get you over the hump. Truth is you stand a better chance of a successful first finish French polishing than applying nitro. (French polish is more forgiving and can be simply repaired at any time in the process and after completion.)

First off you do not apply coats. Understanding this is the first step to success. It is imperative to understand the goal, steps and order of each process in French polishing. It is not merely raging on shellac. Each step prepairs the way for the next and affect the sucsess of both the previous and up coming process session.

French polishing builds one continuous film by melting one body session into the next. It is leveled as you go by spiriting-off between sessions. When done with attention there is no need to ever sand a French polish finish

I will tell you that one of the worst things you can do is to sand shellac. There is a much easer way to fix issue. Even in leveling out the film.

Also It should take no more than 8-10 body sessions to build the film thickness. I can say that if you have 20 body sessions on the guitar you are taking off more than you lay each session. That tells me that you are working too wet.

If you will give specifics as to problems you are having I will be glad to help. It would also be useful to include fairly close and clear photos to refer to.

Michael

Only about a gallon of olive oil! Just kidding, I have done the spiriting off thing and it has been curing for the last 4 days. I just do not know how to remove all traces of oil without damaging the current finish. I realize nitro will not stick to waxes or oils.

Is it possible to have a matte finish with shellac?

I'm just looking for possibilities.

Well if you had been spiritting off after every body session after the second or third anyway as you should, after about a 15 min set time ther would be no oil in or on the finish. this again goes to understanding what each process does. sanding the shellac only traps sanding dust and sanding grit in the shellac. it can be done but I do not recamend it. it is much faster to stiff-off wet If you are dead set on removing the film or a majority of it. you can have all the shellac off in under and hour. you can have any trace of oil off in 3 min. Now that is provided you used extra virgin olive oil. If it did not say extra virgin then you do not know what it was cut with. But even then I would bet you would be ok in most cases.

First the oil you used each session should have been no more than 2-3 eye drops. If the oil was of the right purity it would migrate to the top of the film near instantly. And been removed by the following spiriting off session if you spirited off regularly.

The only time you will ever get a build of oil is if the oil purity was poor and if you sued way too much.

Michael,
Thank you for offering help on this subject. I will submit photos this evening. And l will list with it as much detail a possible of the problems I've encountered.

Just a note, I have been using the link I've found on shellac.net as to the french polishing guide. Along with any and all infomation at the local library. Not to mention all the posts on this subject on the OLF!

I'll post again in a few hours,

Thanks,
Rob

Cool I will be glad to help if i can. I will tell you that most tutorials have you spiritting off about evry 3-4 sessions. that is not enough. that leaves you with too unlevel of build in my opinion and I think Colin would agree as well. if you spirit-off after the second session and every session ther after you build your film level as you go. you never need to touch the film with sandpaper.

Any way I will save the boring details for addressing your problem spots later.

I've seen this topic come up more times than i care to count while i've been a member on this forum. And Michael has been very helpful each and every time.
So speaking as a guy who's thinking of fp'ing his first guitar too, how about posting a toot/faq in the turorial section on this topic?

Frank

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Frank

Well I have been putting together one but have been waiting for a new build where I use FP so that I can include photos. This year every order and build I have taken has used either lacquer or poly finish. I am still here and more than willing to help at any time plus in May I will do better than a tutorial. See FP guest seminar post.

Michael:

When you say 2 or 3 drops of oil are you saying to use that much oil everytime you load your pad with shellac or is that the total amount of oil for the entire bodying session?

Michael:

When you say 2 or 3 drops of oil are you saying to use that much oil everytime you load your pad with shellac or is that the total amount of oil for the entire bodying session?

I will give quickly a few tips on things I see regularly done wrong or miss understood by finishers new to French polish

1)The process of boding.

Many first timers assume that the way the film is built is a process of padding shellac over the top of shellac. This leads inevitably to the finisher, in an attempt to speed the build applying the shellac to wet. If the muneca is miss loaded to the point that if you tap it on a piece of white paper and it leaves a singular wet circle on the paper the muneca is too wet.

Too wet of a muneca with shellac will take off more shellac than it leaves behind. Too wet with alcohol will wipe off both that is being laid down and move that that has already been applied.

A properly loaded muneca will leave a spotty and not very wet circular pattern on the paper. Most of the shellac that will be amalgamated into the previous session is coming from the residual shellac in the inner pad.. the new load of a few drops of shellac acts only as wicking agent to give a free flow path of the residual shellac through the outer muneca. Too much alcohol will make the inner pad residual shellac too diluted and cut too thin and leads back to taking off old shellac rather than amalgamating new shellac into the old.

2)Spiriting-off

Most tutorials I have seen recommend spiriting off after every 3rd body session. Personally I find this to be too little. If you properly spirit-off after most every session you will level the film as you build it.

The firmness used and technique of presenting the muneca to the body during spiriting-off is also critical to the process. You will not properly level if you use and intermittent stroke or if you place the muneca don on the surface. The muneca should glide on and off each edge in a singular non stop motion. The firmness should be firm but not restricting.

This process is vastly under used in my opinion and will make the difference in having to abrasive level or not. It also in my opinion produces a firmer film if done often during boding.

3)care of the muneca

I see many use t-shirt material for their outer covers. This is a 3 dimensional weave. It will leave a fain ripple affect during boding but that gets melted by spiriting-off. The real problem in t-shirt material is that the 3D weave also traps dust and other fine particles tht get delivered with the shellac to the film. If you use t-shirt material you must change the out cover very regularly.

I find linen and muslin to be much better outer pad material. I still change my outer pat at the first sign of contamination. But linen and muslin does not trap dust in the weave near as bad because it is a flat weave. If you have dust contamination you see it on the pad. With t-shirt material this is not always the case.

Also you should store your muneca in a Ziploc of other air tight container between usages. Even if while waiting 10-15min between sessions.

I could go on and on but this will do for a quickie.

The point of the oil is only to reduce the friction of the muneca when the shellac is at proper viscosity. Only use enough oil so that the pad does not want to stop during boding. It is really as simple as that. One or two eye drops is all you need and some times only one spread over the face of the muneca after the shellac and alcohol load up once you have the hang of boding.
It also aids somewhat in the visibility of the volital alcohol cloud seen behind the path of the muneca as you body. this cloud is important to see during boding so adding one or two eye drops per load will not hurt a thing. It will all be removed after the body session sets up a short time during the spiriting-off before the next session.

I actually found that I only had to add a small drop occasionally, not even every time I put a few drops of shellac and alcohol on the muneca. I also started using a pad of paper towel to dab my muneca on, and found that it really helped me work dryer, which in turn helped me build better during the bodying sessions.

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Waddy

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Sound Clips of most of my guitars

as long as you are not draging you got it right

Hey Michael,
Sorry I'm late. I did not realize it was wed night Church
Anyway, here it is in a nut shell. I had originally planned to use nitro as a finish. My prep (grain filling)was with z-poxy filler and several wash coats of Zinser Seal Coat. (100% wax free) I then had a change of heart after handling and playing an FP guitar. I purchased some almost blonde shellac flakes from Shellac.net After some reading of posts here on the OLF and what I could find at the library, I proceeded to assemble my components for FP. Wool socks, canning jars, denatured alcohol, and some linen I did not think my wife would miss Also some extra virgin olive oil.

The shellac was measured by weight and the alcohol by volume. The first session was with a 1lb cut. It was reccomended by link on the shellac.net site. Using the pad or muneca, I started by adding 6-8 drops of shellac inside the muneca, then a drop or 2 of oil on the outside of the pad and started rubbing in circles. I saw the tell tale cloud behind the pad on each pass. I had to load the muneca twice to do just the top. I would always finsh with a straight pass with the grain of the end of the body. This did not seam to make the swirls go away. I let it set for about 20 min and repeated the process.
I did this 4 times and then I would let it set overnight. The next day I started the spiriting session. I used a clean pad with only about 5 drops of alcohol and dragged the pad with the grain starting from one end to the other without stopping.
That was when things went bad. It seemed I was removing all the shellac I had just applied.(algamated)
So I decided well lets sand this thing down flat and try again. Soft sanding pad, 400 grit wet/dry and the oil.
This is the outcome.

Not very pretty. I also get a lot of little specks in the finish. The worst pin hole I tried to fill with CA. Then sand and re
body. Unfortunatly this is what happened.

See the white ish area on the upper bout.
I hope this was enough info. I never did get the spiriting thing down so I simply replaced it with sanding. I could see now that it was a bad move.

Any help would be greatly appreciated,
Thanks,
Rob

What happened to the pics????
Let me try again.

Fist thing I notice you mentioned nothing about the preparation of the inner pad. At least 10-14 hours before you start any process you should saturate the inner pad with 2# cut. Squeeze out till it will not drip and allow to set out over night this will harden some. It should become the consistency of soft toffee. You should be able to mead it but if you squeeze it, it should not leak. This is the heart of shellac that will lay down the film. Starting from wet shellac in the inner pad can lead to the issue you faced.

When you start boding you add 3-6 eye drops of shellac to the out side of the pad followed by 3-5 drops of alcohol. This creates a wicking action that melts and draws shellac from the inner pad. The add 1 or 2 drops of EXTRA VIRGIN olive oil or Walnut oil to the face of the pad and spread it with your fingers over the surface of the pad. Now tap the pad on a sheet of white paper till the dispersment pattern is spotty not solid. Now the pad is properly loaded. Apply in moderately firm figure eights not circles. Figure eights fold the shellac into its self more evenly. Always watching for the cloud. The cloud should be disappearing quickly as you go. If you make a single figure eight and you se the cloud for more than a split second behind the muneca then you are using a tad too much alcohol. Once again the cloud should be about an inch behind the path of the muneca and last only a split second. I find that the boding process is much dryer process than 90% of first time French polishers intuitively think

Now here I depart from almost every tutorial I have read most say to spirit-off every 3-4 sessions. Funny thing is that I have known and worked with several old timer furnishing finishers including my grandfather. The all taught me that to build a level and hard film you must spirit-off after every body session has set up, starting as soon as you have a base film. This on guitars is after the second body session. Also to spirit-off properly you must understand the task at hand. When we spirit-off between body sessions the intent is to melt high ridges and fold them in. If we make slow deliberate passes we wipe the melted shellac off. If we make firm-ish but not hard quick passes we melt the high spots and fold the shellac in. Spiriting-off too wet with a too slow of a pass will do as you say remove too much shellac. The spiriting stroke should glide on at one edge, firm but quickly straight stroke to the other edge and glide off. Spiriting should never be circular or figure eights and should always go from one end to the other in a singular quick stroke. I like to think of this process much like rag buffing paste wax shoe polish.


Anything I have mentioned so far that is outside what you did?

Anything I said so far leave you with any questions?

Good morning Michael,
Thank you for your input. You are correct sir about me not preparing the muneca properly. Also my error with the bodying technique. I also failed to mention that I did not use any filler on the soundboard. No pumice was used on this guitar.

At this point, am I better to strip the guitar and start over?

I have a question, I have a question, call on me, please!

You said prepare the inner muneca before starting any process. Does that mean, at the end of the day, you re-prepare for the next days sessions, or just at the beginning of finishing the instrument?

_________________
Waddy

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Sound Clips of most of my guitars

I never fill tops. I do size tops with egg whites and seal or spit coat the entire guitar with 1 or 2 1# sessions prior to starting to body. This gives the first body session something to melt into.

Now is it too late or do you need to start over. it is never too to repair a French polish. It all boils down to "Do you want to invest the time?" you will spend, probably equal amount of time either way you go. But will finish a month earlier due to cure time.

If you decide to nitro the guitar you will have a 3-5 week cure before rub out. If you decide to finish up French polishing you have just a few days before your finish with the finish and a few more days to allow it the cure. So that choice is yours.

That one area on the top lower bout looks as if you really pulled off a bunch of shellac while spiriting-off. This is a clue tht you’re a bit slow in your passes and maybe too wet with alcohol. Most of the rest of the body looks good but the head stock looks as if something is in the film and the pores don’t look fully filled. Is the back the same with shallow pore recesses?

Waddy ,

The inner pad continuously gets recharged each time you load the muneca. You only need to prepare the inner pad one time if you store it between sessions and over night in a air tight container once you start boding. Unless you let it dry to fully hard. If this happens you first add alcohol to soften it some and 10-15 drops of shellac. allow to set in the open till it again reaches the soft toffee consistency

Krugerr you said you used a new outer cover to spirit-off. this is not needed as long as the outer cover is not soiled. A new outer cover will drag off too much shellac. This is even more the case with T-shirt material.

When I spirit-off between sessions I add between 5-7 drops of alcohol and one drop of oil the outer pad and make the passes I described earlier. I get about 4 passes with each load up. It takes about 4 loads to spirit-off. Oh and do not go back over a recently spirited off section. You can do multi spiriting sessions back to back but allow time for the shellac to set up before repeating.

Another thing I notice is you have masking tape at the FB extension area. This is not a good idea. The alcohol will pull out the tape adhesive and contaminate both the muneca and the film.

Thank you Michael! So, when you first charge the Muneca, you leave it out in the open over night, rather than putting it in a jar with a few drops of alcohol?

_________________
Waddy

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Sound Clips of most of my guitars