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I'm following the 'Milburn guitar tutorial' on French Polishing to put the finish on my first guitar. I'm at the end of pumice filling phase but it looks splotchy in places with a hint of white haze and roughness from the pumice. Is this right? Should I move on to the bodying stage? Any advice would be appreciated.

Sounds like too much shellac during the pumice fill. If you remember they mentioned that it would be better if you lost your shellac during filling

Two things that you need to be sure of is that you are using very little shellac and that you clear the pumice on the muneca before using. The pumice should go clear from the solvent before you touch the guitar or it will leave splotches as you mentioned in perticularly if you have overloaded the inner pad with shellac. The roughness is cause by a buildup of pumice suspended in shellac.

This is probably the hardest type of fill to pull off for a first timer. It really takes practice on scrap before attempting on the guitar. Once you get past this issue you will have learned most of the pitfalls of first time French polishing

To correct the issues add no more shellac to the inner pad and with a clean outer pad add 5-8 drops of solvent and sprit-off till you level out the film. You will be removing shellac so you will need to replace your outer pad often. This process will take several spriting passes and you will need to add solvent as you work. The object here is to remove the film built up on the surface. If done right it will not pull the fill out of the pores. The object is to clean off the the film on the surface.

Sorry for the bad news but don't be down hearted. This is the typical first time result and is part of the learning experiance.MichaelP38882.5114351852

I didn't use any shellac during the pumice fill, only alcohol and pumice on the muneca. I cleared the pumice on the muneca before application by putting drops of alcohol until the pumice was grayish translucent, then tapped. Perhaps I used too much pumice?

How exactly should the surface appear after the filling stage?Marc38882.5301273148

That could be as well as too much shellac on the spit coats I suspect that you used too much pumice as us mentioned. Anyway you have pumice trapped in shellac. and ned to remove the film down to surface level. The best way is spriting off. The quickest is sanding but will likly require ne spit coat and some fill.

Okay thanks, I'll spirit it off.

What exactly should the surface look like at the end of the fill stage? Shiny, dull, clear, smooth?? How do I know when I'm done and ready for the body stage?

level. clear but dull and smooth. If there is a gritty fell to the film ther is still pumice trapped in the film.

For future refferance it takes very little pummice per load to do the trick. It is not really the pumice that is filling the pores but the fibers the pumice sands off the wood surface. a too thick of spit coat can prevent the pumice from pulling the fibers or even getting to the wood so it will have no place to go but get trapped in the shellac.

Got it, that explains a lot. I think I used too much spit coat and too much pumice. It's smooth and dull over about 90 percent but there are patchs of dull and gritty. Thanks for your help.

Thats what Lance pays me the big bucks for........Wait he doesn't pay me.....Hmmmmm     MichaelP38882.6147916667

it kinda funny, I am moving into a bedroom shop and feel that spraying will be out of the question, so I need to learn FP. Every single time I see a question about FP guess who answers with tons of easy to understand knowledge. MichaelP.. I have learned much more from your advise then all the tutorials I have read. Its clear you follow the quote you have in your signature line   "The true measure of the craftsman's soul is the sum of all he has learned multiplied by all he has taught."
Just wanted to say thanks,
Mike

Ditto on the cudos to MichaelP, he knows his stuff on this and a host of subjects. I hope to get out to west Texas and meet Michael someday, my brother has a second home and Ranch in Taos, New Mexico and we sometimes head down to the Gila Wilderness area for some riding and if it gets me close again, I plan to pull myself, my horses, boots and all and see the man and his shop. Odessa is just not one of those towns on my normal beaten path. I would call first of course!

Mike
White Oak, Texas

GarshMichaelP38883.383125

Thanks for the kodos guys

I would like to take this moment to say that for any first time or experienced knuckle rubbers out there. (French polishers) I don't think I will ever pumice fill another guitar. Not That I have problems doing it. But it is a lot of work that IMO can be done much quicker and with better results using many other types of fill. My personal favorite is Zpoxy. I also like egg whites. While I am very much a traditionalist when it comes to French polish film application. I am not one that holds that pumice fill is the only way to fill a French polished piece.

The place that I once really liked pumice fill was on wide pore woods. Because it used fibers from the wood to fill with. But after some practice pieces I have to say I think Robbie O’Brian has a great method using thin cut shellac and end grain dust for this situation. I won't go into the process because I had rather you get Robbie’s DVD. It is worth every penny and many dollars more.

I guess what I really am trying to say is if you have never tried French polished finish before and do not want to spend at least a couple weeks practicing pumice filling and the other process, then I recommend that you use a simpler to master fill technique. Pumice fill requires that you fully understand and know what to look for in the way of problems to avoid situations where you have to back-up and repair what you have done. It is the one time when you are deliberately adding a contaminate to the surface that can dramatically affect the film build. Either practice to proficiency, pumice filling prior to using on a completed piece or you are likely to take a long walk down the road of knowledge, back in the direction you started from. This is not always a bad thing in the long term. The school of hard knocks tends to teach lessons well.

Remember practice first and practice to completion. You need to understand the interaction of all the process to understand how one process relates to, and can affect the final finish

I have to agree with Michael, I did my first dozen or so guitars using pumice fill, then one day when I was opening the pumice container it slipped and fell onto my shop floor, pumice everywhere. Well it just got swept up and thrown out. I wanted to get the back filled and had read about epoxy fill, so I gave it a go with 30 min epoxy (I now use finishing resin). Boy, am I glad I dropped that pumice. I scrape and sand it back so that only the pores are filled.   No way would I go back to pumice.

Can I too say that even though I feel I've got the FP process well sorted now (25 instruments) I still learn something everytime Michael posts on the subject.

Colin

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

If a man speaks and there's no woman to hear him, is he still wrong?

I asked my wife this question and she asked me to tell you, "YES" She should know she is always right MichaelP38883.4777199074

[QUOTE=MSpencer] Ditto on the cudos to MichaelP, he knows his stuff on this and a host of subjects. I hope to get out to west Texas and meet Michael someday, my brother has a second home and Ranch in Taos, New Mexico and we sometimes head down to the Gila Wilderness area for some riding and if it gets me close again, I plan to pull myself, my horses, boots and all and see the man and his shop. Odessa is just not one of those towns on my normal beaten path. I would call first of course!

Mike
White Oak, Texas[/QUOTE]

Mike I have a better idea. Let both meet at your brothers home in Taos. It is a heck of lot cooler there 104 yesterday here 101 today.

That sounds good to me, he goes for a week or two every 4-6 weeks. I go about 4 times a year for a week. It is a really great spot, big Adobe Hacienda on about 8 acres with Horse facilities, We have some great friends there and a pretty large number of Texans with either second or permanent residents there. We do alot of riding there and trailer to some really beautiful areas with lots of wildlife and streams. Lot's of great music and musicians in Taos, had the pleasure to meet and play with some as well. I will give you a call on my next trip up and you can bring some of those pretty guitars and we can have a ball. Always an audience in Taos to listen to some good playing. It is also enjoyable to visit downtown and the square, spin a few yarns of days gone by in the life of a cowboy with the tourists.

I will stay in touch, you are always welcome

Mike

Mike I would love that. My Gandfather had a ranch north of Taos many years ago. My Grandmother sold it after he passed away...Darn. I love that area and the town. I use to ski there regularly in my 20s and 30s and still fly fish in that area when I can get away.

P.S.
I love to ride MichaelP38884.488287037

I would just like to add that I purchased Robbie's FP DVD and as a first-timer it is working out great. I would highly recommend Robbie's DVD to anyone interested in learning FP. I used system 3 epoxy on this one as a pore filler and it is working out very nicely. I found for me that mixing the epoxy 50/50 with Alcohol and wiping on with a paper towel was the way to go, it may take a coat or two extra, but it leaves a super smooth coat and very little sanding.

Greg

_________________
Gwaltney Guitars

When I experimented with french polishing, I actually had a rather easy
time filling. What I couldn't seem to do was get anything resembling a
glossy finish.

Proper glazing is what brings the gloss to French polish. It is not a quick process if you are looking to achive high gloss by hand rubbing. If impatiant to get there you can sand with micromesh through 12000 then use a uato glazing compound or even a high speed buffer with med-fine,fine and extra fine Menzerna compounds. The same principles that apply to high gloss on lacqure also apply to cured French polish. You do have to keep in mind that it is not as hard aslacqure but outside of keeping the heat down it is the same.

Oh, ok, thanks Michael. I was really wondering. I had put down five body
layers, but in pictures of the FP work others were experimenting with,
their's already seemed glossy!

Probably had oil showing and looked glossy. But if viewed after spriting off I am sure they would appear duller. That said I have a question. Have or did you sprit-off after every body session from the second session on? I personally feel this is important, and I know it aids the shine comming out sooner because it levels and polishes as you go. Most tutorial say to sprit-off after every other or more session. but I am a firm beliver in after every session. I rarly have to sand to level because I agressively sprit-off after every session. This helps keep ridging down and somewhat pollishes as I go. Now I let every body session cure an hour before spriting-off. This helps eliminate pull off. Glide on and glide off with your spriting-off stoke, going in one direction only till you have done the intire surface. The repeat from the opposite direction. Use a faily firm stoke but not so firm you drag. kind of like polishing leather shoes or stroping a razor on leather.MichaelP38887.6382175926

I would like to think I was intentional about spiriting off, but I'm not
entirerly sure. I know I'll definitely revisit it when I have an actual
instrument to finish!