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I started french polishing a guitar, and had to stop mid-process about 3 weeks ago. My question is, if I want to continue
do I have to do anything to prep the surface, or can I just start where I left off?

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Matt Jacobs

"Don't tase me bro"

Matt,

Just pick up where you left off. One of the great things about shellac is that new coats will partially dissolve previous coats - more appropriately described as sessions if you're doing FP - creating a chemical bond between the two. This characteristic is also one of the weak points of shellac: it can be re-dissolved with alcohol after it's fully cured, unless it's 100 years old.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Since it has been three weeks, do a spirit-off on each session prior to boding. now the question is have stored your inner muneca in an air tight container? Really I don't think your old inn muneca will be in working order regardless. You should prep a new one IMO

Michael.
My pad gets grubby pretty often, and I'll just dump it in a jar of alcohol and wash it out and squeeze it out in a cloth, dry. Basically start from scratch with it.
What can you tell about my method from this?
I go through a lot of pads, I make up 6 or 8 at a time and when one bothers me, I just start fresh. Maybe I use 2 per guitar.

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With regards to spiriting off, the question I have had is does it really matter if you spirit off with alcohol? I have been just wiping off any excess oil that has risen to the surface with a dry cloth, then carrying on with FP'ing. Seems unnecessary to spirit off all traces of the oil, just to add another drop of oil to the pad when you resume the next session. What am I missing?

Thanks,

Jason

Contrary to popular belief, the intent of spiriting off is not solely to remove oil. In fact removing the oil is really a side affect. The intent of spiriting off is to melt and level the ridging left by boding. It is a very necessary process in build a FP finish.

So you put both the inner and outer pad in alcohol?? Doing as you described delutes the cut of residual shellac in the inner muneca. It sure would seem to me you have no Idea what cut you are working with. it is much better to discard the outer cover as it gets gunky.

Thanks - that sounds like a defensible reason to do it. So, if there is no ridging, or swirl marks, there is really no reason to do it then?

No there are severl other reasons to spirit-off. You will never get me to say that there is little or no need to spirit-off because in 35 some years of French polishing I have leared it is one of the top 3 of the 3 major processes and in my opinion the most over looked process. So you are kind of asKing the wrong person to agree with you on this topic.

If you are useing a muneca and bodinig in inter connecting figure eights there is no way you don't have ridging and or swrils. Plus spiriting off helps to polish and if done right helps keep the film level as you build if you do it after every body session. Also cuts down on the amout of glazing required and helps build a harder film

My seminar at RedRock CC next month is specificly geared to aquaint the students with the value of spiriting off after each body session. Come if you can I think you will be suprised what you will learn spiriting off does for you

Just for conversation why are you so intent on eliminating this process? I ask earnestly. Not to make fun or anything.

You see my confusion on this comes from knowing that each process plays a part in the success of subsequent processes.

I'm on my 10th or so guitar, french polished, so not claiming to be an expert by any means. I have been taking them to the buffing wheel after a week or so curing. This takes care of any ridges or swirls. So really, I don't do any spiriting off, and have not seen a downside to it. The finish is clear, polished, level, all the attributes you'd want. I do use 100% pure anhydrous ethyl alcohol, so there's no water in it. Not sure if that is letting me get away with things you wouldn't with denatured alcohol? Could you describe what "spiriting off" is to you? Maybe we're not talking about the same thing. I am thinking wiping off with only alcohol on the pad. I tried this in early attempts, and found I had pad sticking problems, and it would pull little fibers off the cover, so I quit doing it, and with seemingly no ill effects. I'd love to come to your session, but distance is a factor. Thanks for offering your advice. If I'm risking a problem with the finish down the road, I'd rather know about it now. What sort off ill effects might arise later?

Thanks,
Regards,
Jason

Well with out going into extreme detail because my next installment to my tutorial is boding and spiriting off here is a brief description of spiriting-off.

Spiriting off is the process of melting over ridges and swirl marks cause by the figure eight motion and fabric weave of the outer muneca. As well as an means of leveling and amalgamating this melted shellac in to the film

Spiriting off load is a high alcohol load (6-8 eye droppers as apposed to the type 3-4 of the boding process) added into the muneca, and only a drop or 2 of new shellac just to maintain the wicking action of the inner muneca.

The spirit-off stroke starts at one end, gliding on and ends at the apposing end, gliding off and always IMO form one end per session. Never back stroking The next session start at the other end. This is a straight firm and quick motion overlapped by approx 1/4 of the muneca width.

Intent: To knock down high spots, level the surface and fully melt in to a continuous film. This also remove lube oil from the surface.

This stoke is much like buffing shoe wax. Firm and quick but in only one direction per session.

Jason if you are just bodying on shellac, wiping off with alcohol, allowing to cure, then buffing out you are only using 1/3rd of the French polish process. And this will make a fine finish. That said being a purest of some part I have to say I could not call that French polishing be case the 2 process I feel are most important in building the depth of luster and best hardness are left out. I am not knocking it. It will make a great looking finish I am sure. But it is a short cut or hybrid padded shellac finish.

If it works for you then all is fine. My self I prefer to be a traditionalist when it comes to French polish. And that is what I teach. No need to ever touch with any kind of abrasive, buffing wheel or compound and still achieve ultra high gloss if desired by means or the other 2/3rds of the process

Oh and on the lint issue I suspect that you are likely not using well worn muslin or linen for you outer muneca or rag that you use to wipe off with. New cotton or flax fabric has micro fibers left in it from the textile plant. it takes many washings or lots of wear to shed all these. Another possibility is the method of cutting. Cutting into shape with straight edged shears (scissors) and especially cutting with a knife will open the weave up to shedding fibers at the edges of the square. Use pinking shears instead

Thanks Michael. Really appreciate your time to respond to this question. It fills in some blanks for me that I was unclear of before.

Is very fine weave silk an option for an outer cover? I understand the WWII parachutes were silk, and thus may be a good solution for the outer cover. I was told silk is low lint as well. I have access to one, thankfully my grandfather didn't have to use it during the war.

I have a couple of questions. First what is your inner muneca made from. how are you prepairing it for use.

I have never use nor heard of anyone using silk. I am not sure how well it conducts the wicking of the residual shellac. It may work very well. but I do have some doubts but they may be unfounded.

My inner muneca is Dr. Scholls lambs wool. I start out with a golf ball sized clump (dry). Wrap my outer cover over (old fine weave bed sheet - thought it was Egyptian cotton, but maybe a poly blend in there too?), twist it up tight, then give it a full eye dropper of 1lb cut, dab my finger in baby oil, then transfer the drop from my finger to the outer cover, then start padding. (This is after two heavy spit coats with no oil). As long as I keep it moving, it doesn't leave lint. I probably apply 5 -10 eye droppers full over the course of about 1/2 hr., once it starts to feel draggy, I stop. As I progress, I start to use less solution in the pad each reload. I have a feel for the point just before it starts getting so draggy it pulls lint. That's where I stop. I keep going until my pad is dry before I reload, giving it a dry shine/ buff for a few minutes. I only add oil if I start to feel dragginess. I then repeat for the other side of the guitar the next day, so once a side is padded it gets rested for a day or two before the next session. Before I start the next session, I just wipe off the surface oil with more of the bed sheet, in rag form, and then carry on. Always 1 lb cut, and keep doing that for about two or three weeks, until the finish has good depth and smoothness. Then a week hanging in a sunny room, then to the buffing wheel, using Grizzly's fine, and very fine instrument wheels/ mazerna compound. After a session, I put the muneca in a jar, pour over a bit of pure alcohol, and put the lid on. I usually change the pad cover once or twice during the several week process, not because it's gummy, but it starts to get thin from use.

Thanks for the info. To let you know, I did a quick spiriting off, and them went right back into it, so far the results are pretty good.

I love how these french polish threads stir things up.

_________________
Matt Jacobs

"Don't tase me bro"

So you never pre load the inner muneca (IE saturate the inner pad with 2# shellac and ring it out till it does not drip a day before and store it in a air tight container to harden to the stiffness of soft taffy.) From your explanation then until there is a fair amount of residual shellac built up in the inner pad then you are applying the load to the surface not wicking the residual out of the inner muneca. Here again i am not knocking what you are doing but until you have done several body session you are more less just padding on shellac as apposed to the "traditional FP application" of melting and wicking the residual semi hardened shellac from the inner pad onto the surface.

Tell me is the shellac appear wet (shinny) or slightly less that wet and more creamy in appearance directly behind your pad as you work? Do you se the vapor cloud of alcohol evaporate behind the pad as you body? Here again not being critical just asking.

I had not preloaded with 2# initially, but I like that idea for when I start a new inner pad. Makes good sense, I'm going to start doing that. I have been using the same inner muneca for a year or two now, I think it's on it's 4th guitar. By now I have a good build up of residual shellac in the pad, and my finishes keep looking better, so that's probably because I didn't have a well loaded residual build up initially, and over time it has gotten there. As I pad, it looks wet for about the first 3-5 seconds of padding, then transitions to a short lived vapor cloud, that flashes off in about 1 second, then after about 30 seconds, no more vapor cloud. Then I buff a while with the dry pad, and then recharge. I certainly don't interpret your responses as negatively critical. I am trying to improve my methods, and the only way to do that is to invite critique. I probably am making the traditionalist in you cringe, so thanks for sticking with me on this!

I was hoping not because I was wanting to learn how you were doing it for my ino as well as maybe help out if I could.

From what I am interpreting you are pretty much bodying but not spiriting off and not glazing. But rather doing an alcohol wipe down. You are buffing between each body session then a final buff out after the shellac has cured out. that is interesting. I do hate to hear that you are laying down wet at first because a wet pad actually removes a portion of the previous applied shellac. You can probably eliminate that from your process by tapping the muneca till you se a spotted report on paper prior to actual boding. I also from years of doing this know that you have to apply wet if you are not seeing the vapor cloud. In tradition method the shellac being applied is all coming from the inner pad. Each load is only a primer to keep the residual shellac wicking. if you loose the vapor cloud it means the inner pad's (lower portion) has run out of alcohol and therefore the wicking will stop because the shellac starts setting in the pad. If using a cotton outer pad you would expect the drag to be to be severe as soon as you no longer see the vapor cloud. Now the silk outer pad may very well be helping over come this somewhat but I would not expect so for long.

This has been a very interesting discussion. I have seen many FP hybrid techniques before. Most I would not really consider in truth to be French polishing at all. Yours applies the body session “not quite but mostly” traditionally. How ever I feel that you are likely building a film that is not quite as hard as it could be. Not seeing and dealing with one of your finishes that is only an opinion based around my knowledge base.

From your picture your work looks great and in the end that is what maters to you. That said I do invite you to follow my ongoing tutorial “French polishing per Michael Payne” I will be adding t it each week till it is done. I am trying to focus on understanding what is happening in each process rather than just a how to. I am no technical writer by any means. Fortunately for me after my first post Steve Cortright step forward and is going to proof and edit the each edition for me. After the text is finished and as soon as I have the opportunity I am going to add photos to go with it and post a link to download the whole thing from when complete. Feel free to ask questions on the ongoing tutorial post if you have any.

Thanks Michael, appreciate your advice, and will be following your tutorial with much interest.

Jason