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Hello all. I had another filling session last night. Here is what happened. I am still using cheese cloth for the inner because I can’t find wool (I called 4 fabric stores, and Wallmart to see if they had wool socks) and T-shirt for the outside.

I charged the inner core with a 1 lb. cut shellac and an equal amount of DA. I then put a drop of olive oil on the outside and rubbed it around with my finger. I then beat the daylights out of the pad to distribute everything. I then dabbed the pad on a piece of paper and saw wet and dry spots, so I think it is wetted well. Next, I bit an amount of pumice and clear it.

I only worked 25% of the back. It took about 45 minutes, but the pores are filled. Here are my questions:

1)     Does it take this long? Remember I only did 25% of the back.
2)     Sometimes after my charging process outlined above, I get a lot of haze. The haze is reminiscent of freshly applied car wax on a car.
3)     I have a beautiful coat of shellac where I filled. Is this normal? It seems like I’m bodying and not filling. Isn’t all this shellac preventing the filling process? There aren’t any wood fibers to use to fill because they are covered. However, it looks like I have the same results as Fernandez.

Thanks guys!!!! I am making progress.

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

Yes it takes a long time to fill using pumice.

It sound like you may be too shellac wet. Keep in mind the the fibers that the pumice pulls off are near microscopic.

You should not have to pounce the pounce into the pad that hard. I tap my pad into some pumice. clear it on the pad with Da and oil if you want and go.

I have not gotten hazing as you described. I think it is time to test your shellac. Put a drop or two on a plate glass for 48hrs. I should dry clear and hard enough that you have to use pressure to make a fingernail mark in it.MichaelP38408.4468634259

The haze you're experiencing could be from the oil. That's what happened to me, and left me really frustrated until I figured out what was going on. Try spiriting off the finish on the section you have done. I know, many talk about saving this until the end of the whole FP process, but you can do this at the end of each session without harm, and it might give you more confidence to see that pretty shine even in the early stages. I'd suggest charging a fresh pad (no pumice or oil) with the same diluted 1lb cut you've been using (it's the alcohol that removes the oil, but it doesn't hurt to add a whisper of finish at this point). Then go over your test area quickly and lightly with the grain (you can press harder in later bodying stages, but in any case, don't linger with the pad). If the haze disappears, it was the oil. If not, it could be too much pumice, and you'll have to do some sanding. By the way, save that new pad in an air-tight container for later use.

Shellac wants to shine right away, but it's not hindering the filling process. The pumice is still cutting the fibers, while the shellac in your pad covers the area just scraped by the abrasive. It's this continuous mixing that glues the fibers into the pores.

Yep, it take some elbow grease and time to fill the pores. I'd suggest doing a larger area at a time, say the whole back (or even back and sides), then going back over it the next day to complete the filling. Then on day three check for missed pores and rough spots and work on those. Ya gotta cut yourself some slack and not worry about getting it all done and all right the first time. I'm still a beginner at this, and am not fully pleased with my results yet, either. The beauty of FP, though, is you can proceed with the knowledge that you can remove any mistakes with alcohol, sandpaper, or both without harming the wood!

Carlton

Very good call Carlton,

Doug he is spot on. Even with just shellac layed downd ther is a bit of a dull look till spriting. I don't do this during filling normally but I do it after every second body session to remove access oil and it lets me know if I have under covered an area, and there is nothing wrong with doing it during filling. I would for peace of mind still test your shellac, I do this before I start every guitar even if I just cut a new batch.

Ok guys. Thanks for all the good advise. I don't expect perfect results the first time, but you are getting me closer. I'll let you know how I make out over this weekend as I hope to at least fill the entire back.

Thanks,

Doug Ubele

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

I had my third filling session last night which was a start of filling the bottom half of the back for the first time (The previous 2 seesions where the upper back).

I am in trouble. After an hour of filling last night, I all of a sudden created a "gummy" patch about the size of a silver dollar. I immediately stopped.

I let it sit overnight and picked up again the next day. The patch wasn't gummy anymore, but I could see a change in color where the patch is as compared to the rest of the guitar. I thought, "maybe I should spirit off the top". I did with light passes with a new pad charged with only alcohol. The "gum" came back immediately as I passed over the patch. I then tried to rub it out with alcohol. It moved as I did that. I then tried 600 grit sand paper and oil. No luck. It is still there.

I let it sit for 2 hours and came back. The patch was dry and not sticky to the touch, so I tried to fill over it. It is still there. I also created another patch in the process

The other strange thing happening is I am getting brown spots on the bottom of my pad. These seem to be occurring where I place a drop of olive oil. This didn't happen during sessions 1 and 2.

Please help.

Thanks,

Doug Ubele

P.S. -

I found a place that sells raw wool and bought 8 oz. I also bought some medium weave linen. I tried it out. The wool seems to really let a lot of material out. I guess it doesn't absorb like cotton.

I am also testing my shellac on the bottom of a glass jar as I don't have any plate glass. My shellac is J.E. mosers super blond flakes.dubell38409.7503125

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

Doug--Ouch! It's an adventure, isn't it?

This is a tough one. It kinda sounds like you spent too much time on one area. I've certainly done that. The shellac starts building up faster than its ability to dry, and tends to congeal in mounds. Or, since you've been using a very light mixture of shellac, maybe you went beyond the point where the pores were filled, and the pumice/fibers had no where else to go.

You might be facing some more elbow grease to remove those built-up spots. If the alcohol and sandpaper aren't working, you might use a scraper. Just be careful--if you don't don't have something small enough to shape into a scraper (a small plane blade, a squared-off edge on a piece of glass or razor blade, etc.), be sure to mask the outside edges of whatever you use so you're only scraping the mound, and not into the wood on either side!

Good luck!

Carlton

Yes it is an adventure. I really thought I had this filling part down. I gave it a good sanding after my reply above. I sanded dry with 400. It did not take long to get back to the wood. I didn't sand so much as to expose new pores.

I think I need to make sure I have a pad charged with the right amounts. Each time I charge, what are the amounts below. Should I charge with shellac everytime?

1) Alcohol - How much? 1/4, 1/2, 3/4, or 1 teaspoon.
2) 1# shellac - How much? 1/4, 1/2, 3/4, or 1 teaspoon.
3) Pumice - How much 1, 2, 3, 4 pinheads worth.

Carlton,

You mention above that I should "keep the shellac application light at this point, otherwise you'll end up with a gummy mess (speaking from personal experience)."

Could I be using too much shellac?

Thanks,

Doug Ubele

P.S. - My basement is at 45% humidity and 60 degrees Farhenheit.

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

First charge with 20 drops from an eye dropper 1# shellac, 10 drops DA and seal in an air tight container over night. Next day charge 5 drops shellac 3 drops DA, You should be ready to start. Use medium firm but not too hard pressure. This would be a good time to practice on scrap. get your technique down before moving on to the guitar. If you are using a soft wood for the top (spruce, redwood, ceder) there is no need to fill the top.

Michael,

You use more shellac than DA. Can you read my problem 4 posts up? Do you think this was caused by too much shellac? What's your take to the problem I am having?

Thanks,

Doug Ubele

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

I am not sure what the problem is. You may be over working the area. You mentioned brown spots on the muneca. this is typical of sticking. have you had issues of the muneca not gliding but having to be pushed or dragged as you work. a sticking muneca Will leave a build similar to what you are describing. If you are sticking than the shellac is building too fast and is congealing behind you. and the next pas over repeats the problem. or the muneca is dried out and dirty.

When charging a muneca for the first time the object is throughly charge the inner pad with shellac this shellac is pushed out in the boding sessions. The DA that you add to the muneca as you work helps dissolve the shellac loaded in the inner pad. if the inner pad clogs sticking will accrue. If the pad is not stored in an air tight container when not in use the inner pad will clog.

There is so much that is going wrong for you that it is time to set down with the Milburn or whatever tutorial and carefully read and determine where the errors are happening. If I were there I could probably help but not seeing, I am just guessing. This is a good learning experience. Once you get past this. I promise you will never have this problem again.

Yeah, as soon as I charge my pad it starts dragging. I went through several outer covers, but it didn't help. I get this brown spot immediately....it's gummy. Should I use less shellac?

I have read the Milburn tutorial and have the Fernandez video. I was pretty thorough in read/watching, but will go over them again.

Thanks,

Doug Ubele

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

If your dragging as soon as you start something is wrong. I don't think that the issue is to much shellac in the inner pad. i would first suspect the outer pad as not having good transfer. If things are going good you should have to charge the outer pad about every two or three min. of boding.

Try this with a loaded inner pad and new outer pad load 5 drops of shellac and 3 drops of DA on to the outer pad. Tamp the muneca on a clean white sheet of paper till you just get the fingerprint effect. now add 2 drops of (extra virgin olive oil or 100% walnut oil) on the center of the muneca. No pumice. With this you should be able to get about two or three min. of glide. Be sure to stop before the muneca starts to stick. Watch for the cloud. If the cloud disapears then you are draging the muneca. If the muneca is dragging it is leaving ridges inbeded with cotton fibers. This is what is causing you messy build up. This is the basic body stroke. Let make sure this is working before we add the pumice.

As soon as you see even the smallest non shellac color or any other foreign matter on the muneca change the outer pad. If you get dust or any grime on the muneca It will either trasfer to the body or cause the muneca to drag though the film.MichaelP38411.6236226852

I'd say you're getting some good advice from Michael P. I usually dilute the shellac with about an equal amount of alcohol (though I don't measure exactly), but what he's suggesting still results in a pretty thin mixture, since you're starting with a 1lb. cut anyway.

I've been ending up changing my outer wrap frequently, too, and I think it may be because the weave is too tight. I'm using 100% cotton t-shirt type material, but I think it might be too crisp and new, and is blocking the free flow of material from (and back into) the inner pad. I'm betting it'll work better with much-washed cotton, as the fibers get softer and more open, as the experts recommend.

I'd go with Michael's suggestion of starting without pumice to find a good application technique. In fact, since some experienced builders successfully fill with no shellac other than their initial wash coat (just DA and pumice), MP's early bodying approach might be a better way to a smooth surface in less time (and with less sanding!). The DA/pumice mixture would work with the shellac already on the surface, so the fibers will adhere in the pores well. I'm gonna try that approach on my next project, too.

I still get the impression that you're spending too much time on one area. Try working the whole back, or completely around the sides in each session. For example, start on the upper right bout of the back, without going over any one spot more than two or three times. Then proceed to the left upper or right lower bout, and so on, all the way around. By the time you get back to the beginning, that shellac will have had time to dry enough that your next swirl won't pull it up and turn into congealed goo (unless you press too hard). Now here's the hard part (it was for me): only make two or three circuits around the back, and stop. If your first session is in the morning, you could go back and do it again at night, but otherwise leave it 'til the next day. I think this more patient approach will result in a better finish faster, with less time spent on fixing goofs.

I know, Ron Fernandez and others make it look like an easy two-day job, but they've got the experience. That's why the FP technique seems so mysterious. It's like learning to PLAY the guitar. Ya gotta practice before you can get on stage with Christopher Parkening.
Somebody should put together a 100-hour tutorial, following someone from his first session until he gets it right. Then folks like you and I wouldn't expect perfection from the start. We will get it eventually; then someone will ask, "how do you do that?," and we'll try to explain it, but he won't be able to do it well until he puts in the time, either.

Carlton

Ya got to crawl before you walk, Ya got to walk before you run. YA got to practice before you execute. Here lies the Law of Shellac. Follow this law or you will have to sand it back!!!!

Ok, guys. First of all, thanks for all the help. The support has really been great.

I read the Milburn tutorial again last night. CarltonM and MichaelP, I am confused why I am using shellac at all during filling. I think you both are referring to the tutorial as a must read, but Milburn doesn’t use shellac during filling. In fact, they insistently point out to not use it. Here are some direct quotes for the tutorial:

“We will not be using any new shellac during the entire pumicing process. This is very important- additional shellac during the pore-filling process will inhibit the operation. We will be using the already dry shellac "spit coats" that we have previously applied to the guitar. All that is used is the muneca loaded with alcohol and a very small amount of pumice applied to the muneca surface.”

and

“Do not use any shellac while pumicing. As Eugene Clark says, "You would be better off if someone stole your shellac at this point." Your muneca must touch the surface of the wood. A heavy layer of shellac would prevent this.”
and

“Use no shellac or oil during the grain filling process. The spit coats of shellac with the alcohol, combined with pumice, will be all that is necessary to fill the grain.”

I hope you don’t think I am questioning you both, but hope you see where I would be confused.

Last night, I took some new raw wool and balled it up in a new outer cover. I added 20 drops of 1# cut shellac and 10 drops of DA through the outside cover. I sealed the muneca in a glass jar overnight. I will test it out without pumice as MichaelP suggested above.

Thanks,

Doug Ubele

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

Hey, when it comes to building and finishing guitars, question everybody!

As I mentioned, some knowledgeable FP-ers only fill with DA and pumice--no shellac other than their wash coat, and no oil. The people you mentioned are considerably beyond my skill level (and probably always will be), and I'd say do it their way and see how it works for you. On my first try I didn't use extra shellac, per their instructions, and it didn't seem that I was getting much pore filling done. That's when I started using a very diluted cut of shellac, and then some oil, in the process, and it worked better for me. That being said, I probably didn't excercise enough patience in my early attempts to find out how to make it work. The Milburn/Clark method must be effective, 'cause these guys know what they're talking about!

I know you'd like a Ten Commandments of French polishing (so would I!), but a lot of people have been FP-ing over a very long period of time, and it seems like every one of them does it a little differently. I guess it's like the difference between cooks and chefs. Cooks follow recipies, chefs take the same ingredients and make it up as they go along. But even chefs have to start somewhere, so yeah, learn from the best! I've studied the same folks you have, and found even more on the 'net, and it's all simmering in my brain 'til I come up with my "best" technique. It can be extremely frustrating, but keep trying things until it works for you.

Carlton

Ok. I added 5 drops of 1# cut shellac and 3 drops of DA on a new outer pad. I also added 2 drops of extra virgin olive oil on the center of the muneca. No pumice was added because we are testing.

I got a good cloud for 10 seconds. After that it disappeared. I repeated the process and got the same results.

Again, my inner core is raw wool, right off the sheep. The outer cloth is 100% cotton. It is the same consistency as good T-shirt material. Not the underwear kind, but the kind you would wear as a "shirt".

I remember getting much more cloud when I was filling. When I initially started this, I was added a lot more DA and 1# shellac (about a 1 second squirt from a plastic bottle. I have my DA and 1# shellac in dispensing bottles that I bought from USPlastics).

What do you think now?

Thanks,

Doug Ubele

P.S. - I want to test that Zpoxy and compare it to pore filling. Where do you get that?

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

Get some Doug I think you will find That you like it. I feel it make the deepth of the more intense onder the finish.MichaelP38413.3865509259

[QUOTE=Shawn]
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.[/QUOTE]

Shawn, don't tell every one, this is supposed to be a well kept secret of the Cremonese violin makers, chemical analysis of varnish flakes by David Hume and Charles Beare, in my lab, show that albumen is present under the varnish. I believe the pore filling is just a by product of the process. This has been known for a long time and used by instrument makers for centuries. I believe Joshua amongst others uses it.

ColinColin S38413.4021990741

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

Where do you get it?

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

Doug you might check local RC hobby and craft supplies. If they don't carry it Most will order it for you. If no luck there do a Goggle search and you will find many vendors.Pacer the manufacture makes several formulas of Z-poxy I recommend the finishing resin. It takes a bit longer to dry enough to sand 6Hrs but flows a lot better. I have hears of many using the 5-min. with good results but I like the flow-out of the finishing resign.

This is glue. Seems like a lot of people in this post use it. I'm surprised there is something else like a grain filler that people would be using? How do you apply this stuff......swirl it around with a plastic scraper?

Thanks,

Doug Ubele

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

Mix in a mixing cup, pore small amount on the surface and squeegee in with a credit card or a single edge razor blade with the edges rounded so it will not gouge the wood. A little goes a long way, and it is not glue it is an epoxy resin i.e. has more uses than sticking things to gather. It dries clear very very very slightly clear amber. sands very good. The longer time cure resin the better it sands. That is why I say use the finishing resin zpoxy and it has better clearity than the 5-min.MichaelP38413.6376273148

How about Stew-Mac's ColorTone Waterbase Grain Filler? The reason I ask is that I am placing an order with them. I can't find Z-poxy locally, and would have to pay more dreaded shipping.

Thanks,

Doug Ubele

P.S. - Can I apply ColorTone or Z-Poxy after I seal the guitar. I already sealed with 2 applications of 1# cut shellac.dubell38414.4853125

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