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Anyone care to recommend a good pore filler that isn't epoxy? I'm not quite ready to deal with the possible hazards of epoxy and have already heard enough people with serious reactions towards zpoxy that I can't be sure if it's something I want to use. Also it does seem rather unforgiving in that epoxy doesn't sand that well, and if you sand through them it shows forever.

Currently I use this latex based stuff that just gums up sandpaper in short order, and doesn't even do that good of a job at filling. It has coarse particles that actually scratches the wood if I squeegee it across the grain, and when finally leveled it would still sink a little bit... I heard good things about oil based fillers but I can't find anyone willing to ship it to me.

I remember seeing a Robbie O Brien video about using drywall paste as pore filler by coloring it to match the wood... I tried that and other than the fact that some drywall paste has a gray tint (which messes things up a bit) drywall paste sands real well. Unfortunately it does not like lacquer and still sinks quite a bit.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I use Goodfilla water based pore filler and Famowood water base pore filler . Abt = IMHO.

Try a denatured-alcohol soaked rag to remove the excess filler, rather than sanding. (only with water-base)
Also recommend Famowood WB filler.

The micro bead acrylic paste filler from LMI is inexpensive and goes a long way. I use it on hog necks, as there I find epoxy a pain. Safe and no issues with shipping.

I've started using egg whites and probably wont ever use anything else.

Please tell me more about egg whites. I've read about it but have not tried it.
Any tricks to apply?
Dan

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What ever you decide to use, make sure it is compatible with all the rest of the coating chemicals you plan to use --- by that I mean contact the technical support of those products. We are talking about potential long term issues arising so its much better to play it safe.

Having practiced what I just preached I was assured by the Pacer techs that Zpoxy is compatible with nitro lacquer finishing chemicals. I like the clarity and easy sanding.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I would suggest using the French Polish method of filling. It works really well, dries very fast and is stable under most finishes.

How you do it is apply a couple of coats of French Polish with a mouse ( cotton wad wrapped in a cotton cloth). Let it dry and then use A new mouse with French Polish and a small amount of Mineral oil and some pumice. The pumice acts a bit like sandpaper grinding the previous coats of shellac into the pores of the wood. You will actually embed pumice/shellac/wood into the pores and the shellac will bind it together. It is a bit more work than just spreading a filler on but will give you a perfect filled surface.

I suggest try it on a scrap of wood and give it a try. I think you will be surprised how well it works and who knows you may end up enjoying French Polishing more than any other means of applying a finish.

Cheers,
Bob

I plan and have from the beginning to do FP. It's a safe way to go from what I have researched so far. I bought some alcohol 96.5% that is food grade so you don't have to worry about additives. You can still be effective from alcohol fumes but from what I read, an open window with a breeze is enough. I have a mask/respirator just in case. Pumice is the filler along with the oil and shellac as stated before. I watched some vids from guys doing furniture with FP and some older guys were using some beeswax before FP. I do not have any further info on it. Good luck Taifu

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久保
美智え

Can you give a bit more advice on this? I've tried pumice filling several times, but never felt like I was doing it right.

My first problem is that the pumice shreds the muslin pad cover much more quickly than it does the wood. Are you using a tougher fabric for the cover, folding it over several times so you have more layers to wear through, or what?

Second problem is that it takes a ridiculous amount of alcohol to keep the pumice/wood slurry soft enough to move around. How large of a pad are you using, and how wet? Do you ever have to dump puddles of alcohol on the guitar to keep an area soft enough to work in?

We've discussed this to no ends on acousticguitarconstruction for a small shop as Kencierp will attest to. Some guys say just a coat of shellac removed with a steel wool brushing works great.


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There are a number of FP youtube videos on porefilling with pumice..This method has also been thoroughly discussed on delcamp classical gtr forum.For an older guy like me.It/s far too much work and time consuming.Ionly use the pumice/oil/shellac to flatten thin built upon coats Of FP shellac.It aids in creating a clean surface. Then I can restart the FP process. It.s much easier to find a filler one feels comfortable using, and then use either shellac , varnish, FP, laquer or whatever,.. on top of the filled surface.

CrystaLac is a good pore filler. Just make sure you have a couple seal coats on the wood before you put it on. It can soak in unevenly in different places and you can get a blotchy finish. You have to be careful not to sand through it too. But it goes on easy, cleans up with water, and sands easy.

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Jason Moe
LaCrosse WI 54601

I found that the water borne "clear pore fillers" Hood, Hydrocoat etc. have a lot of silica in the formula. On the dark Rosewood, Walnut etc. after three coats the clarity is gone and a matter of fact they begin to take on a "whitish cast" Also -- you have to sand every particle off and leave chemical only in the pores or make sure you have perfectly even coverage on every square inch of the guitar -- otherwise the bare areas and those with lighter coats will appear blotchy under the top coat. I wanted very badly to make one of these type products to work, but they in themselves caused more work. And I personally never achieved satisfactory results.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Jason, I have good results with CrystaLac as well. My process is a little different. For me sealing is optional, as I sand back to bare wood leaving it only in the pores. It is easy to work with, not messy, and you can find an application method that works for you. In fact you need to, as the instructions are sketchy at best!
Mike

Hated it... It doesn't really have any filling capability and takes about 4 or 5 coats to get any kind of filling out of it and when I did get it to fill the end results had a blue-ish cast to it. I threw away the quart and will never to use it again.





It does take some finess. I use soft cotton like an old T-shirt but you can use (and it is recommended to use) linen or an old sheet.
I find a mouse about 1.5" in diameter works best for me but people use all sorts of sizes. The reason it is sometimes called a mouse is a lot of people like it the shape of a mouse so they can hold it in that palm of their hand but I don't like to get FP all over my hands.

There is a trick in using pumice and that is not to use too much. I get a pile on a sheet of paper and then just touch my finger to it and then rub it on the mouse. The mouse should be wet enough to not leave any dry pumice on it. The mineral oil is what will lubricate the mouse and make it work smothly but too much and it won't work as it should. I keep checking the outer cover on the mouse for signs of it starting to frey. If it does then I open it up and move the wad slightly so the worn part is not being used.



That is where the mineral oil comes in. The center of the mouse should remain damp with FP and you should keep feeding it when it starts to get dry. You can tell by tapping it against your hand and you should feel the FP just slightly coming out. You will just dab your finger in the oil and lightly rub it on the outside edges of the mouse where it makes contact with your work. I will work a spot about 6X6 inches and as soon as I feel a drag I will put about 3 or 4 drops of Alcohol and about 6 drops of FP on the mouse right in the center of your working surface. Dab it a few times on the palm of your hand and then go back to your work surface. If it feels like it is sticking then just dab your finger in the oil and go around the outside of the mouse again. You will also want to twist the outer cover to tighten up the wad which will release more of the FP to the outside.

I have had a couple people PM me about doing FP so maybe I will think about doing a small video on it. I have seen a number of vids on Youtube, some good and some bad but I have not seen any explain the balance between FP alcohol and mineral oil and keeping that balance the same throughout the process. To me, that is really the trick to doing a really nice job. It is extremely important when you are doing the final polish and getting a nice shine without rubbing it out with compound (which to me defeats the reason for French Polishing in the first place. You should end up with a beautiful deep gloss without sanding and rubbing it out.

It takes a feel for it but I can attest that once you learn how you really never forget how it should feel when you do it right.

Cheers,
Bob

I have had very good success with Durham's Rock Hard Wood Putty, dyed with transtint to match the wood I am filling.
Does't take much and it goes a long way.

Seal the wood (I use shellac)
Mix up a little, add the dye and then keep adding powder until it is a little thinner than pudding. Then squeegee it in the pores. Sand back. Repeat if you are inclined as there is a little shrinkage.

I have also tried the egg whites. That is also a good method, but a bit messy. I also found it a pain to sand back. Shrinkage was definitely an issue down the road, so two coats are recommended.

Pumice was a pain. Experienced similar results to those posted above.


There are many things you could use for pore filling. You just need to find one that works for YOU.

Good luck. And for goodness sakes, practice on scrap.

I've had serious trouble with lacquer not adhering to shellac so I would never use shellac under anything. I do not know if it's the particular brand of lacquer I use or the shellac, I tried pumice on a Warmoth neck a long time ago and basically later the lacquer topcoat flaked off in sheets. The worst part is shellac is very hard to sand.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I also like the LMI micro bead stuff. It's the only water based filler I've tried that wasn't junk. If you dilute it to thick cream consistency, it will fill in two applications. Wipe with a wet rag after it flashes, just like traditional oil based filler. It typically takes a little light sanding, so it's not quite as easy as oil based. OTOH there's no smell and cleanup is easier.

All the other methods are several times more tedious.

Well "To Each His Own" as they say.

I personally would never mix dis-similar finish materials as you say with shellac and lacquer. It is all FP or all Lacquer for me. I know some have had good luck with them I don't think they have been time tested like using lacquer sealers and lacquer finish or all French Polish have. It is my belief that they guys that are mixing epoxy, shellac and other finishes will see a large failure rate after time passes.

At least that is my personal opinion. I guess time will tell if I am right or wrong but I know my finishes will be stable for many years to come.

Bob

Thanks, Bob! I'll try a 1.5" pad with T-shirt cover and oil. I've never used oil in the pore filling stage before, due to fear that it would soak into the wood when the base shellac coat is softened and leave it blotchy looking. Walnut oil should work just as well, right? I don't have mineral on hand, and would be more comfortable with a drying oil.

On a related note, I recently polished a top using no oil at all, and had much better luck than in the past with oil. Specifically, it makes it easier to judge what's going on. With oil, the pad glides smoothly and surface looks shiny the whole time. Without it, you can see the actual state of the surface, and the pad only glides smoothly if it's loaded correctly. Too dry, too wet, or too much shellac compared to alcohol, and it drags.

But for pore filling, maybe the oil really is necessary to keep the guitar surface from drying into pumice sandpaper and tearing up the pad like always happened to me in the past.

I'm not sure a video would be particularly helpful. Seems the only real ways to learn are hands-on experience with a teacher where you can feel the pad after it's properly loaded and watch close-up what's happening on the surface, or trial-and-error followed by asking questions about specific problems like this. So thanks for answering

I mean I never had bad luck as far as reaction goes with water based filler, it's just so far ones I have used are kinda hard to use. I never tried LMI filler and was afraid to try it. I tried Stewmac's Crystalac and hated it. It is not completely transparent and really hard to sand.

I have always not used oil and ended up using a ton of pumice and alcohol because the pad keeps sticking. I only read on a really extensive guide on french polish not to use oil in the pumice step... but French Polish is kinda time consuming and the shellac goes bad fairly fast. I was having so much problem with french polish and only realized that the shellac I have been using may have been bad. And even then the shellac isn't all that durable. It's probably fine for classical guitars but steel string players would want something a little durable...

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

FYI and FWIW - Traditional french polish technique involves flooding the wood with oil as a first step, and rubbing in pumice, brick dust, silica or whatever -- to fill the pores as necessary. It could be argued that skipping this step means it's not french polish at all.

For obvious reasons the oily fill method is not traditionally done when finishing guitars. The oil free method is much more difficult and tedious, but I personally wouldn't feel comfortable flooding a guitar. Then again, a small amount of drying oil mixed with pumice is probably not the end of the world.

Timbermate.

Just use 320 grit paper and dip it in the egg whites (in a bowl) then sand in a circular motion. The sanding will tear fibers and create dust and the egg whites act as a binder. So you will make a dust/egg white slurry which fills in the pores. It usually takes two or three coats. Then just sand back with the grain. I go back to 220 for that.

I had my doubts at first but it works surprisingly well and your customers will get a kick out of it