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I am attempting to french polish my EIR guitar and am having an allful time of it. I can't seem to get the pores to fill in. It looks blotchy and nothing I do seems to help. I've tried more pumice, and less pumice. I've tried more and less alchol. I'm about to sand it all off. It just looks like $%#@. HELP PLEASE
Jeff

Do you apply a wash coat before the Z-Poxie?

Jeff - I'm finishing classical #2 now. Both were FP over EIR. I used pumice on the first, and had many of the same problems as you describe. I used Zpoxy on #2. The pumice will probably never come out of the cabinet again.

There is word of mouth here that epoxy doesn't stick well to shellac, so I used no wash coat.

Jim

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Jim Kirby
kirby@udel.edu

Jeff,

Pumice filling is not an easy technique and it takes a lot of time. The best description of the process I've seen is the one on the Milburn tutorial. Their mantra of lock away the shellc is right on. You are basically using the pumice as sandpaper that sands small wood fibers mixed with the shellac and puts these in the pores. You don't want too much pumice either - when you get a build up you put more alcohol on the municea and move the pumice to another spot. You will wear through the municea covers pretty quickly and need a good supply. It's a case of doing small areas at a time and keep going until all the pores are filled - which can take a long time. Also you need to have the back/sides with enough (but not too much) shellac on before you start the pore filling process.

I does look blotchy but when you have the pores filled and start to build up the body coats of shellac I find that the blotchiness goes away. It's a lot of work and practice but I love the look you get at the end of it.

Having said all of that, Z-poxy will do a good job too but as the others have said you will need to sand off your shellac back to bare wood to apply the Z-poxy.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

What Dave said.

I used to pumice fill but have long moved over to Z-poxy, though on my next guitar I will be going back to pumice for purely philosophical reasons.

Where pumice is useful is in the repair of a French polished surface that has scratch marks. I think the Milburn tutorial covers that as well.

Colin

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

Though you may be able to make it work, I'd be hesitant about trying to get epoxy to 'stick' in pores that have already been coated with shellac (and some pumice). My recommendation would be to push on with pumice with this project, and move to epoxy with fresh wood and a fresh guitar.

A couple of thoughts:
Pumice does come in different grit sizes- adding (or changing) to the extra-fine type may help.
Having less than a glass-like surface is considered OK by many- you may decide to just have some pores showing.

I know how frustrating FP is- I kicked and cursed through my first FP projects, and I'm still not happy with the results. However, others seem to think they look OK.

Hang in there!

Cheers
John

Bummer is right. The same thing happened to me and I will never do pumice again. After having trouble with the back, I finished up the whole back struggling with the pumice, sanded down and went with Z-poxy over the back, sides and neck to make sure the look was about the same all over the instrument.

For filling, less pumice and small areas reduces build up in my experience. More alcohol tends to cut the shellac and makes it less sticky. But the FP itself after you fill the pores is hard to beat for depth and feel. Good luck.

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

I attended Marshal Brune's Class on F.P.'g. He and his father, Richard are truely experts. I learned a great many things there, however, I guess the two main things I learned that would help you are:

1) Less is more
2) People who want F.P.'d guitars to look like they were sprayed sprayed with poly or nitro should NOT BE SOLD a guitar with F.P.

I looked at guitars made by all the masters, including Brune's own, and the finishes were nothing like my customers want them to be.

So my advice is sand it back, start over with some super fine pumice. Remember #1 above and if the the guitar is for #2 Talk them into Nitro or poly or whatever. All else fails smash the guitar into a thousand pieces and make tooth picks from the remains

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Dave Bland

remember...

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

I tend to agree with both of the suggestions above as I have experienced the same results as you. As far as the video's I have seen of doing a FP job in one day, The best I can think of to say about that is ^%$#&*^%%$& dont believe it!

Take your time. The muncea should be almost dry as you apply the coats, Use a salt shaker to distribute the pumice and work in very small areas at a time. Let the guitar "rest" for days between sessions to gas off properly too. Use your face to tell if the muncea is too wet. You should barely feel any moisture on it when you touch it to your face.

With all of that said, using z-poxy is the best method of filling pores but you need to do that first before anything else is on the guitar.

 

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Reguards,

Ken H

[QUOTE=Hodges_Guitars] Use your face to tell if the muncea is too wet. You should barely feel any moisture on it when you touch it to your face.[/QUOTE]

Well, I dab the muneca on the back of my left hand. It took a couple of days to get the shellac off after doing the FP on two guitars- obviously I was having trouble getting the muneca dry enough.
I'm ugly enough without putting a big blotch of shellac on my snoot!

Cheers
John

I have never done any FP, yet, but something I read said to always tap a piece of white typing paper before going to the wood.  It acts as a blotter, and you can see if the muneca is too wet.  Tap until it's not.  The paper can also be used to dust a little pumice on - spread out - then just tap into the dusted area.  Some day I'll try it.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Pumice is a lot of physical work. Waddy's suggestion with the paper is good, both for checking the moisture of the muneca and loading up a dab of pumice. I have my working supply in a salt shaker. I shake a dab onto copy paper, cut a very small amount onto the muneca and then put a drop or two of alcohol on it. I then rub it with my finget tip to make sure that there is no dry pumice on the muneca before going at it again. Z-poxy is way easier and more consistent.

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Jim Howell
Charlotte, NC

Thanks everyone for your input. I don't want to give up, but I want my gutar to look good. I will keep trying. I'll keep you posted.

Something that I've seen for dispensing the pumice is to wrap it in a cloth. Tie the cloth closed and tap the cloth on your workpiece to dispense the pumice through the tiny openings in your cloth.

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

The pumice should NEVER be applied directly to the wood. The muneca should be used to pick up some pumice from a piece of paper, then cleared with alcohol. See the Milburn tutorial for the correct way of doing it.

Colin

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

I learned from Milburn, I haven't read it in a while though, anyway this is what I do, FP technique is difficult to articulate with words so this may or may not work for others:

I put on three semi heavy coats of shellac initially then let it dry for a day or two. I then dab a pinch of fine pumice on a muneca damp with alcohol, no shellac. I then put a few drops of alcohol directly on the pumice on the muneca until it is cleared gray-wet on the muneca. I gently rub and spread the pumice into the muneca with my finger. Muneca can't be too wet, can't be too dry--damp. Then choose an area and rub in figure 8's, being careful not to stay too long in one spot. I let dry for a day, then repeat, another day pass, then sand with 800-1000 grit. It's then filled and smooth as silk but satin not glossy. From that point the first bodying of shellac then goes on glossy and smooth.

[QUOTE=hogan] Do you apply a wash coat before the Z-Poxie? [/QUOTE]

NO>>>> never but epoxy over shellac!!!!!

[QUOTE=JohnAbercrombie] Though you may be able to make it work, I'd be hesitant about trying to get epoxy to 'stick' in pores that have already been coated with shellac (and some pumice). My recommendation would be to push on with pumice with this project, and move to epoxy with fresh wood and a fresh guitar.

A couple of thoughts:
Pumice does come in different grit sizes- adding (or changing) to the extra-fine type may help.
Having less than a glass-like surface is considered OK by many- you may decide to just have some pores showing.

I know how frustrating FP is- I kicked and cursed through my first FP projects, and I'm still not happy with the results. However, others seem to think they look OK.

Hang in there!

Cheers
John
[/QUOTE]


Good note here you never>> or at least I would not use pumice with a grit less than FFFF. Corser will likely ball up on you. Use as little shellac as possible and work small areas till filled. This is the most time consuming part of the PF process.

I really would not sand back to bare wood and epoxy fill. The epoxy system should only be used prior to any shellac on the guitar. It is no rumor!! Epoxy will not adhere well to shellac. The other way around is fine.. shellac over epoxy that is. But never use epoxy over shellac. It is like putting hot candy on wax paper. Once the epoxy sets up it will peel right off the shellac. In fact very thin coats of shellac were once used to coat cooling boards in confectioneries (candy shops) to prevent candies from sticking to the boards.