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So basically all I've ever finished or refinished instruments with is Nitro, but I've gotten on a better health(for me) kick, and am trying to be kind to the environment, so I'm starting to use F.P. shellac.

I'm wondering if you should or need to sand back a FP finish in between bodying sessions, say like you would with a sprayed lacquer finish, or can you carry on with the body sessions until you have enough build to enable you to level before your final finishing sessons.

Any help will be appreciated.

Thanks,

Cal

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Remember, there are no stupid questions, only stupid answers!

The purists will tell you that you never need to touch a FP finish with abrasives once you start to build. The leveling occurs during the spiriting off sessions after each bodying session and in the glazing process.

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Waddy

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Sound Clips of most of my guitars

Yep I one of the two purists here that will tell you I never touch a FP finish with sand paper.

The trick to building a level film as you go spiriting-off between each body session. This is the topic of the seminar I am giving at Red Rock Comm. College May 23rd and 24th.

Since French polish system melts the new body session into the previous that is no need for a tooth since you are not applying coats but rather building a singular amalgamated film. properly spiriting-off is intended to melt down any high ridges left between body session. Now in order to build this film level as you go means you must be consistent with your boding session application coverage and muneca loads. This is why most people do sand paper level after the all the body sessions are complete. (To avoid having to be consistent on coverage during all eight body sessions)

Now if you asked the same question for basic padding on my answer would be differnt. but the French polish process is no basic padding on.

Thanks, Waddy and Michael,

I didn't think that I would need to sand between sessions, but I thought that I would check with the people that know just to make sure. I've finished my second body session and things are looking good, so I'll carry on and see if I can finish without resorting to abrasives.

I'd really like to attend your FP seminar at Red Rock in May Michael, I'm sure that it will be very educational, but getting there is a bit of a problem for me, will you be doing a video of the sessions and selling it afterward? I'm sure there would be more than a few people on the forum, unable to attend, that would be interested in purchasing a video.

Thanks again for the info.

Cal

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Remember, there are no stupid questions, only stupid answers!

Robbie may make a video, I don't know

Spirit off after every body session from here forward and you should be able to build level with no need to sand level.

I guess I'm the other purist! No, I never use any abrasive once I start to French polish. As Michael said, each spiriting off will level any imperfections from bodying, which should be very few anyway, and the final glazing will give a near buffed finish.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I'm not a purist, but I do get good results.

With FP, I don't sand between bodying sessions. I just spirit off after. However, I do sand with 800 grit after bodying and before glazing... I wait at least 3 days. Then, when done glazing, go over rough patches with 3m perfect-it rubbing compound. Finish rubbing with 3m swirl mark remover. How you apply the swirl mark remover depends on your thrill seeking tendencies. The longer one waits, the higher gloss one gets from rubbing out, I find. It's just another perspective.

I just started french polishing on my projects for the same reason....laquer solvents really stink up my work area.
I'm no pro at it yet. I only sanded areas that I goofed up on....like when a drip runs down the side or I left a big finger print in the soft shellac. Just let it harden over night and fix it with some 600 grit sandpaper and a re-polish.
One tip.....use naphtha to remove the oil instead of alcohol. Naphtha won't dissolve the finish.
I'm a big fan of shellac now....no smell, super easy to fix mistakes, builds up much faster than tru-oil. I completed the finish in 4 sessions on saturday and a touch up on sunday morning.

In French polishing your load should never be wet enough to have drips of any kind. The shellac in the inner bad should be the consistency of a very soft toffee. The load you put on the out side of the pad (a few drops of shellac and a few drops of alcohol + a drop or two of lube oil) is added to start a wicking process from the inner pad. The shellac that is applied to the surface should go on more like a very thin soft paste than like a liquid. The alcohol in the pad is important to in keeping the shellac flowing and melting it into the surface film. It is not like loading a brush the applying a wet coat. As the new load is taped into the muneca it causes the semi hardened shellac in the inner muneca to soften and wick through the muneca and be melted into the previously applied shellac. The melting and re-melting of the shellac film is essential to the process of creating a singular film as apposed to layer over layer.

In turn the spiriting off with alcohol should and needs to re-melt the top surface of the film. Spiriting off is more important than just to remove oil. It re-melts the top surface, knocks down ridging left by the muneca and some what polishes the surface prepping it for the next body session, and by re-melting aid in hardening the film. If you spirit off with naphtha then most of these attributes are diminished or are not achieved at all.

There are many process for what some call French polishing. Not all of them really are French polish nor achieve the quality film that the proper French polish technique renders. Now some are French polish techniques with modifications to the process for faster build and some ad resins to improve hardness. And that is all well and good. However the application processes are important to French polishing and melting new sessions into each other and re-melting the surface via spiriting off are the heart and soul of the French polish process. With out the melting and re-melting then you are just padding on shellac, which in its self is a fine finish but will lack the depth, luster and hardness capable when truly French polished.

Michael, do you use the same pad for spiriting? Also, your bodying pad I believe I read you prepare by soaking and wringing out a 2# cut and then letting it sit open overnight. Is that about right?

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

Yes I use the same pad I body with when spiriting during body sessions as I use for the body session. When time to spirit off I ad on small drop of shellac to the outer pad tap it and add 4-6 drops of alcohol and smear a small drop of oil just to prevent sticking as I first address the surface. I do not tap the muneca after loading the alcohol but rather let it set for about 10 seconds. Yes some shellac is being laid down during boding/spiriting off. But if you attempted this with a pad with no residual you would end up taking shellac off the surface rather than melting and re-smoothing. This is a good time to mention that I change my outer pad as soon as I see any staining or glassy build up. Typically this is about every other body session or sooner if it needs it. This said i have use a padd designated for spiriting but found that it provided me no real advantage.

To prepare my inner muneca I saturate my inner muneca (wool) with 2# cut and ring out just to the point it no longer drips when shaken. I place it in a zip-loc bag left half open over night or until the inner pad is malleable like soft toffee.

Thanks Michael. I usually pick things up relatively easily by reading, but FP seems like a dark art. I get a bit closer with each of your posts.

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

Don't think it to be hard, it is not. IMO the key or the moment of enlightenment is when you understand the reason for each of the process rather than understanding how to do them. If you get bogged down in trying to perfect the application of the processes it is easy to miss the reasoning for the processes but once you grasp the "why" the "how" becomes easy.

Call me "Grasshopper." I recognized that you pulled that line straight from your book.

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

As a complete novice I can only say what worked for me after around 4 bodying sessions (whole top 1 circles, 1 figure 8'd, 1 straight lines) When I ran my hand over the finish I could feel small pimples these I knocked back with 1200 wet and dry in olive oil after doing this twice either my technique improved or I just got lucky and didn't need to touch the finish again really after finishing and leaving for 10 days I used meguiars scratch and swirl remover on it.

It was one of the most enjoyable parts of the build for me I found if very relaxing and more durable than most would have you believe, though I doubt if I ever made a guitar for someone else I'd use it.

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Formerly JJH

I learn more from my mistakes than my successes

You do realize my grandfather (my FP mentor) is rolling over in his grave with laughter at the thought

Did he have a ruler, Michael?

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Michael or Colin could you tell us how you make your muneca and Mike where do you get your lambs wool for the muneca?
Dr.Scholl's?

Spinning and weaving supply shops are a good source.

http://www.villagespinweave.com/IBS/SimpleCat/Shelf/ASP/Hierarchy/0305.html

http://carolinahomespun.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=CH&Category_Code=NFW-P

I think I have a bag of wool that still needs to be carded somewhere around here. I'll look if you are interested. I doubt that its lambs wool though.

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Aoibeann

I got an old 100% lambs wool sweater at Good Will, for $2.89. Enough for 20 or 30 munecas. Washed it a few times to make sure it was free of chemicals.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Thanks Lillian, But I'm hoping that I can find something here tomorrow. I read that even a wool sock would work but I'm even having hard time finding wool socks in Florida. I read from LMI that Dr Scholl's has a lamb wool product but haven't located here yet. If I can't find it tomorrow I might just stuff it with cheese cloth but from an articl I read today they say wool is the best. So I'm wanting to give it try as I've tried one method for the last two days and I'm wanting to try this conventional way now to see how it works for me. An artcle by Bob and Orville Milburn taken from Eugene Clark and Cyndy Burton's technics. I guess I might give a fabric store a try too.


Edit: You beat me Wandy. There's a few of those around here but Finding a wool sweater here might be tough too.

Chris, as a last resort, you can go to Home Depot and buy a Lambs Wool pad for applying floor finishes. They have both the artificial ones and real ones. Shear the wool off of the skin, and pack it in a piece of T-shirt material for the center of the muneca. It is a little fluffy feeling to start with, but once you soak it in shellac, it gets better. Those pads are $5.00 or $6.00, as I recall.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Cool! Thanks for the lead. I think I read that some car washing gloves are real wool also. Waddy do you prefer wool for your munecas?

Hi,
I am about to start my first French Polish. I bought Cotten fill pads. Will they work in place of the wool? Or do I need to go Alpaca hunting?

Cotton will be fine, I always use cotton yarn waste as my fill in my muneca.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.