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This is somewhat jumping the gun and I hope Robbie does not mind me breaking the news this early but In May 09 ( It looks like the 23 and 24 as it stands) I will be giving a two day seminar at Robbie Obrien’s class covering French polishing. i have been putting together a rough synopsis of the seminar I want to give and preparing some test boards with different problem areas. The resent post of Krugerr on the problems he had French polishing brought to mind that It would help to hear where each of you that have recently done your first French polish have had various issues so that I can address them. I have been doing French polish for some 30 years on fine furnisher and cabinets and now some seven on guitars. As putting to gather this synopsis has proven to me, it is easy for me to look past areas that are issues for the inexperienced. Your input would be greatly appreciated.

I believe but we should hear from Robbie to be sure, but I believe the intent is to make the seminar open for all that wish to attend. I am sure as we get with in a few months of the date we will have more specific info.

Just in case you gus and gals missed it, I am asking for specific areas those of you tht have tried French polishing for the first time or several times for that mater had difficulties in and specifics of those difficulties.

At the beginning, and particularly during the pumice filling process, I kept getting these sticky places, like little gobs, where the muneca would grab. Getting those out was always a problem, and many times I just ended up having to sand them out with 800 grit wet/dry and oil. What's the best way to deal with the little sticks that occur, particularly when you are new at it?

Another thing that gave me problems was splotchy finish, which I assume was created by starting with a darker shellac vs using a light blond or medium blond for the spit coats, then building with the darker color. I used dark brown shellac on my back, sides and neck.

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Waddy

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Sound Clips of most of my guitars

Good ones Thanks Waddy

One of the problems I had on my very first attempt was a white area around 4 inches in diameter that appeared under the finish. Not totally white, but like a clouded looking finish. I never did figure out what it was. I sanded down all the way to bare wood and started over, and it went away. I was thinking maybe some moisture had settled in, or I was putting it on too thick. I've never tried the pumice method of french polishing. I always used z-poxy.

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Tracy
http://www.luthiersuppliers.com

Preparing the shellac. Went to pre-mixed because I hadn't a clue about cut and flakes.

Getting a feel for the best application tool. How can I tell a good muneca from a bad one?

Getting the feel for the application. On my first effort I used the shellac far too heavy, or wet, however you want to describe it.

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Expectation is the source of all misery; comparison the thief of joy.
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One of the confusing things for me was understanding how to properly charge (load) the pad for the first time (i.e. new muneca), and then how to do it when it needed to be recharged when bodying.

Some folks say to only load the inner cloth (new pad) with shellac & alcohol, others say to load the outer cloth with it. To recharge a pad, some folks say the same thing (some say apply it to inner, some say outer). Some say not to add alcohol every time you recharge with shellac---only when it's needed (how are you supposed to know?). Regarding oil, all seem to agree to add it to the outer cloth, but some say to add it every time you recharge the pad, while others say only add it when needed.

Then there are those who say use baby oil, others say extra virgin olive oil, while others claim pure walnut oil is best.

I don't know how much of all this relates to personal preferences versus what's the best way to do things when it comes to french polishing. But it is confusing when you're just starting out.

thanks,

john

Howdy Michael,
I'd like to know how much flakes to mix to complete one guitar. I mixed 8 oz of Everclear with 2 oz. of shellac flakes for a two pound cut. It seems like an awful lot. Will I need that much, or could u just cut every thing in half and still have enough to complete the guitar

Which brings me to another question. What pound cut do you use? One, two, or three?

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

This sounds like a now question

1# cut for spit coat and glaze and 2# cut for boding

it is going to take about 1-2 oz to spit coat and glaze and 3-4 to body that said I too mix up 8 ox at a time. it never goes to waist ther are endless uses for shellac around the shop.

As Michael said, he will be in Colorado giving a masterclass at the end of May on his French Polishing technique. What he didn't mention is that he has generously offered to donate his time. As most folks here on the OLF have found out, Michael is very generous with his time and information on all subjects but especially French Polish. This masterclass will be very beneficial for all those that are able to attend. Michael and I will provide more info and details as the time nears.

How do you know when you have enough/too much/too little lubrication? I've had the pad ripped out of my hand because it stuck to wood. This happens with some regularity and is one of my biggest frustrations. Once the pad is peeled off, I have hours of repair to get it back to smooth.

I must be doing something wrong when I hold the pad. On more than one occasion, I've accidentally dragged a finger nail across the top leaving an eight inch, very deep, scratch. Knowing that this can happen doesn't seem to prevent it either. I've even considered taping my hand into a fist.

Michael,
I had a problem with trying to drop fill a small dent on the top with CYA after I had about 3 FP sessions completed, then accidently sanding
through to bare wood while trying to level it. I tried (and tried, and tried ) to refill that bare spot and bring it back to the same condition as the rest of the top. I couldn't find the right combination. First I tried using the regular muneca, and building the film in the blank spot back up. I kept getting a dark ring around the blank spot- I believe what was happening was I was not able to build the film back just in the blank spot, and the area around that was also getting polished was getting darker as a thick film built up. I tried with a special small muneca I made, still had the same problem. I tried sanding the dark area, and the overall look was a little better, but there was still a dark shadow around the original blank spot. I also tried drop filling the blank spot with shellac, but it wouldn't lay down flat-I kept getting a ring around the area like the ring around a water spot on glass. I finally stripped the whole top, and redid the FP. So a section of how to repair damaged areas on FP would be of real value to me.

I've also had a problem getting smooth coats on a top where I had to FP around the bridge. I'd guess trying to FP around the heel of the neck would have the same problem- but I've avoided that by using bolt-on tops and FP the neck and body separately.

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

First off I would never fill a sink or void on a FP with CYA????? I think you mean Cyanoacrylate or CA. Your situation had mostly to do with sanding a crater for lack of a better term trying to body in a film to fill the crater would be very difficult at best because the build up would tend to be at the rim of the crater and not at the middle.

I remember your trials a tribulations or someone with the same situation a few moths back. The best way to handle that would be to stiff off to level, meaning melting and dragging old shellac into the void until level. By means of stiffing or spiriting-off

I'm still stuggling with the pumice fill. I've sanded back to wood twice now.
I had the same problem as Waddy, the sticky mess. I now think it goes back to too heavy of a spit coat.
I think next time I'll use epoxy to pore fill and then go to FP.

Thanks for all your help Michael

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Horton, MI

Thanks Kirk
You are more than likely right either a heavy spit coat (should be 1# cut, 2 sessions max), too wert of residual shellac in the inner pad, or you not clearing your pumice well.