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I started the filling process after 2 one pound wash coats. I filled about 25% of the back and I am unsure if I am succeeding. I started by creating a pad of cheese cloth for the inner and T-shirt material for the outside. I added a bit of alcohol and touched a piece of paper that had some pumice on it. I then began "polishing" the surface.

After 15 minutes, I have small mounds here and the top looks burnished. If I lightly drag a fingernail across this area, I can feel the grain.

What am I doing wrong?

Thanks,

Doug Ubele

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Guitars...One's too many...Twenty is not enough.

I'm no expert, I've only pumice filled one neck, but it sounds like either too much alcohol, too much pumice or both. I think you are cutting thru the 1 lb. wash coats.
I did two wash coats of 2lb. cut shellac. Check out the Millburn tutorial, I think it's on this sites links page, a great resource.
Good luck.

You want the pumice to turn clear on the pad before you start rubbing. The intention is for the pumice to pull small fibers off the surface of the wood and deposit them with shellac into the pores. I did not read you mentioning anything about shellac. It is the third part of the 3 part mixture. It is the glue that bonds the fibers into the pores. If you use just DA and pumice you will get a lump of pumice and fiber built up. Be sure that the pumice applied to the pad is clear and no-longer white before applying, and buff as you would if you were laying down only the shellac

I have a bit of experience with this technique as well. I also recommend the Milburn tutorial - very, very helpful. And the shellac is part of the filling process, as Michael said. To get the pumice clear on the pad I would suggest wetting the pad with the alcohol-shellac according to instructions on the Milburn tutorial and then, with the wetted pad (but in FP tradition, not too wet! ) barely lightly touch the bit of pumice you have sprinkled on a piece of paper. Always better to sneak up on the right amount than overdo it and have lumps on the guitar. Before putting your now lightly-dressed-with-pumice-pad to the wood, rub the pumice around on the rubbing surface of the pad with your finger. The pumice will sort of "dissolve" (it doesn't really) and turn clear. Then you should be ready to fill away!

Best of luck with it,
Viv

French Polish - I have been F.P. for a while now and have very mixed thoughts about it. It is not quick, easy, or even prettier than other finishes. It certainly can be a pain in the you know what! Sounds to me that the problem you are having is as MichaelP explained above. However you can also have problems if the Shellac is Bad...I have one guitar in the works where the Shellac went bad on me...I didn't notice until weeks later when I was supposed to be in the "clearing stage" I have also bought flakes and found them to be Bad right from the start. So make sure you test your Shellac before using.

p.s. I recommend Ron Fernandez's Tape on French Polishing...I just happen to be selling my copy for $25. see my video thread.Dave-SKG38406.42375

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

You will spend three times hours and elbow grease FP than any other finish. It will leave you with a deep since of pride when completed. I have been using more lacquer as of late but I still do FP when requested, and I still love to do it. I have switched however to Z-poxy for filling. It is just a faster technique. and I like the way it makes the grain appear under the film. Which ever fill you use, always practice and become proficient on scrap prior to applying that techneque to a guitar.

Doug,
Let me make one more recommendation. to build your pad Cheesecloth will work. but I would recommend un-dyed 100% wool for your inner-pad. You will find that it retains more shellac than cheesecloth and clogs less. Plus it is firmer, and allows you to be firmer with your bodying which leads to a harder finish.MichaelP38406.4561342593

The lumps are a mixture of pumice and shellac on the surface. You can fix this in one of two ways. First, use a pad charged only with alcohol and work on the lumps, pushing them around and getting them pushed into the grain. This can be slow going. The other technique is just take some sandpaper and sand it away.

You really don't need very much pumice at all. I find if I try to aggressively fill the pores in one go that I usually end up with too much pumice on the surface.

Just try to be aware of what is happening. As soon as you detect the slightest lump build up, lay off the pumice and use an alcohol charged pad to remove the lump. Accept that until you get better at this that you may be going back 3-4 times before the fill is satisfactory.

I never did understand the use of pumice to pore fill. To me it seems like way too much work. I used Z-poxy on my last, and it worked great under shellac. But another technique would be to just make some wood dust from the end grain, and use a 1lb cut with a cotton ball to rub the dust into the pores with the shellac. I know that Robbie O'brien has been using this method to pore fill his classical guitars for years, with very good luck. However, he uses Laquer on top of this, but I would think it would work fine for FP too if you let it cure a few days.
Tracy

It would scare me to use cotton balls. I would be worried about leaving cotton fiber behind. Your right that Pumice filling is a lot more work. That is why I have gone to Z-poxy. But Like the the the old man with the fiddel said " It's TRADITION"

I am using the Millburn tutorial. I don't see anywhere in that article that says to use shellac as part of the mix. In fact, it states to not use shellac when filling. The only shellac needed is the shellac layed down during the wash coat phase. Am I missing something here? Are you guys filling with a pad charged with shellac and alcohol?

I am clearing the pumice, but I think I am using too much. It's hard to specify how much I am using in e-mail, but I am using a small pinch between my 2 fingers. The pumice covers about 25% of the bottom of the pad.

Thanks,

Doug Ubele

_________________
Guitars...One's too many...Twenty is not enough.

If you are using the same pad that you used when you first loaded your loaded your pad you my only need to add a drop of shellac about every three loadings of pumice because your pad should already have shellac loaded in the inner pad. I believe that the Milburn's took this as an understood assumption. you do not want to add much shellac! and you do want to ad more solvent because you want the shellac that you are laying down while using pumice to be thin, about equal to 1# cut or less. The standard 2# cut has the tendency to bridge the pores. That said you still need a thinned shellac to be the bonding agent that holds the micro-fibers of wood in.

When I pumiced filled I found also that a light to modererate amoung of pressure on the fad is best. Don't bear down too hard and "scrub" the surface. Finding the right amount of pressure to apply is another key. When I go to the bodying stages I apply a moderate amount of pressure, just enough to know that I am bearing down on it firmly. Once you get the feel for it everthing falls into place. Like others I now do an epoxy pore fill, it is so much easier to F.P. when starting out with a perfectly flat and pore filled surface (looks pretty good too).

Where can I get un-dyed 100% wool locally. Also, do you guys sand between every stage. I have the Ron Fernandez's Video on French Polishing. He sands right before filling, but the Milburn tutorial doesn't.

Thanks,

Doug Ubele

_________________
Guitars...One's too many...Twenty is not enough.

I get mine by buying hunting socks. I the Northeast fabric stores sell it. for some reason down here everything the fabric stores sell has been dyed. I lightly level sand after every 3 sessions. Typically it takes 8-12 session to build my film depending on what the wood is.

I use no shellac on the pad - just the shellac from the wash coat.

1/4 of the pad covered with pumice sounds like way to much. At least with my technique. For comparison, I try to get a tiny blot on the pad, about the size of the head of a pin. Then I drip a single drop of alcohol on it, smear it around, then go to work with it. When I no longer see the pores filling, I add another tiny amount.

I'm with all the others, I use z-poxy or other epoxy for filling, but I think it's a skill worth learning because we don't aways get every last pore filled with the epoxy. I find it easier to just use a bit of pumice to fill the odd pore that I find here and there when putting down my first coats of shellac.

That's funny michael, I get my wool for the fad from old hunting socks also. I have my wife sew them up just like Millburns tutorial. I have also found that cotton balls work pretty well wtapped around old T-shirts.

Paul S.--You wrap your cotton balls around old T-shirts? You must have some big balls!

Everybody seems to be leaving out an ingrediant in the filling stage--oil. Here's what I've learned: First, a wash coat, then a tiny bit of shellac in the pad, followed by a good bit of alcohol, followed by a touch of pumice, followed by a drop of oil (some use mineral oil; several experts recommend olive oil). The OIL is used to "clear" the pumice. The oil does not remain in the pores. It migrates to the top overnight. You could clear it off with an alcohol-charged pad and a light touch going with the grain, or just leave it there--you'll use some anyway later for bodying. Don't try to finish all the filling in one sitting. Give it two or three days. Got lumps? Sand 'em with oil and 600 grit paper wrapped around a felt block. Wipe it off and continue with pad and pumice.

Why fill with pad and pumice? 'Cause you're filling the pores with wood. With Z-poxy you're filling them with, er, glue! I know, it probably doesn't make any real difference, but the FP method just seems more elegant.

Carlton

Carlton,

This sounds very similar to Ron Fernandez's approach. I am going to give that a go tonight. A few more questions.

1) Is your wash coat 1 or 2 lbs.

2) When you charge the pad, are you "un-wrapping" the pad and applying shellac and alcohol to the inner core, or are you applying it to the outside. Oil and pumice are applied to the outside.

3) How many minutes go by before you have to recharge?

Thanks,

Doug Ubele

_________________
Guitars...One's too many...Twenty is not enough.

Yes Tracy,

You can French Polish over this pore filling method. In fact, you can go over it with any type of finish with no problems as it is shellac that is used with sawdust to pore fill. I use a catalyzed urethane over it all the time with no problems at all.   

[QUOTE=CarltonM] Paul S.--You wrap your cotton balls around old T-shirts? You must have some big balls!

Everybody seems to be leaving out an ingrediant in the filling stage--oil. Here's what I've learned: First, a wash coat, then a tiny bit of shellac in the pad, followed by a good bit of alcohol, followed by a touch of pumice, followed by a drop of oil (some use mineral oil; several experts recommend olive oil). The OIL is used to "clear" the pumice. The oil does not remain in the pores. It migrates to the top overnight. You could clear it off with an alcohol-charged pad and a light touch going with the grain, or just leave it there--you'll use some anyway later for bodying. Don't try to finish all the filling in one sitting. Give it two or three days. Got lumps? Sand 'em with oil and 600 grit paper wrapped around a felt block. Wipe it off and continue with pad and pumice.

Why fill with pad and pumice? 'Cause you're filling the pores with wood. With Z-poxy you're filling them with, er, glue! I know, it probably doesn't make any real difference, but the FP method just seems more elegant.

Carlton [/QUOTE]

Ok Carlton you are using the cotton balls for the inner pad. I have no major issue with that. However I would bet a dollar to a doughnut that the cotton ball will clog faster than wool.

As for charging the inner pad be it cotton balls, cheesecloth or wool with pumice I don't recall anyone saying that. As for using oil to clear the pumice I was taught by a third generation furnishermaker, that would be my grandfather, that the solvent was the agent that clears the pumice. I do not think that a little oil, be it Walnut or extra virgin Olive oil would harm anything. The whole point in Oil though is as a lubricant to help keep the pad from dragging and sticking. By charging a pre-loaded pad with more DA you are affectively cutting the shellac from your original 2# to 1# cut or less. this also help in cutting down the friction caused by the shellac.

Yes I agree that pumice filling is an elegant and very traditional way to fill. However in my humble opinion, and I have been very slow to come to this conclusion.I feel that Z-poxy filling is a better and more efficient way to fill. I am very pleased with Z-poxy filling on FP finish with out the chance of having tiny white specs of pumice traped under the finish. But of cource this would have been a fill and prep oversight. With Z-poxy I feel that I get a deeper 3d affect to the woodgrain when finished.

I do not mean to be opinionated or diss anyone elses way of doing things. Just sharing my thoughts.

Doug--The wash coat I use is closer to 1lb. It's not really critical; just dilute it to what looks right to you. I don't think it's critical, either, whether you charge the pad with DA and shellac from the inside or outside. Once you have a good smooth and tightly-wrapped pad, though, you're probably not going to want to stop to unwrap it for charging. And yes, of course, the pumice goes on the outside of the pad--I gotta learn to 'splain more better! How long you go before recharging is really intuitive...when the pad starts to drag and stick is a good time. Just remember, keep the shellac application light at this point, otherwise you'll end up with a gummy mess (speaking from personal experience).

Michael P....I don't use cotton balls in my pads, that was Paul S. I've been using cotton waste (processed fibers), but haven't really been happy with it. I think I'll try the wool socks mentioned above--thanks, guy's. I'll have to defer to your grandfather's experience--I've read that the oil is what "clears" the pumice, but since I use both oil and alcohol when filling, I guess I just believed what I read without knowing which was doing the job! Sorry if I sounded too know-it-all.

Carlton

not at all Carton. This what we do around. We bounce our thought off each other. Never knowing where they will stick

I use clean raw wool from a breed of sheep that felts. Not all breeds wool will felt but wool fiber viewed under a magnifying glass or a microscope had small barb like scales along the length of the shaft. When wool is wetted and rubbed together it tangles against itself and creates felt.

I use a ball of wool as the core of my muneca and the longer I use it the better the felted core gets. It is still somewhat flexible but will hold its shape better than cotton or other fibers.

To find raw wool check to see if there are any knitting supply stores in your area where hand spinners would go to get wool. They usually will stock small bags of wool (4 oz.) that spinners try to see if they like a particular breed's wool. This size sample will last for a couple yers of heavy use.

Another advantage I find in wool is that the wool will hold liquid (DA & Shellac) but does not absorb it into the fiber so that it give me a more direct reading as to how dry or wet the pad is.

I dont use t-shirt material or any cotton for the outer part of the muneca, I use a medium weave linen. You dont want to coarse or open a fabric but I also dont want too closed a material as a medium fabric will hold and absorb the pumice/rottenstone better than a fine cloth of which the pumice/rottenstone can cake if too much is used at a time. For me it is more forgiving.

Both the Millburn and Fernandez are excellent. FP is an art...it takes time for it all to click but once it all comes together there is no better finish for some things. I build classical so the thinnest finish (that is easy to repair or touchup later) far outways the durability of other finishes.

When I started building the only book I had was A.P. Sharp's "Building the Spanish Guitar", so I learned only old school methods. I am fascinated by things like Z-poxy and water based finishes but being old school, I have not taken the plunge yet.

One really cool "old school" thing that I learned at the GAL conference this last summer was from Geza Burghardt who does not use pumice/rottenstone, he fills pores using egg whites which dry clear. If he wants the egg white filler to add color, he adds color by boiling chicory (cheap in the coffee section of the grocer used for New Orleans style coffee) and adding a few drops of that brew to the egg whites. Geza's techniques have their roots in old world lutherie from violin family builders.

Shawn, I have to say thati agree with you on the wool 100% as well as the linen. I use old t-shirt material but have used old linen. for me the key here is that whatever cover you use it must not shead.

Shawn give the Z-poxy filling a try on some scrap IRW then put a FP finish on it. You get wonderful depth