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OK. I’m tired of trying to get Zpoxy to work with pore filling. After five guitars, I’ve yet to get a consistent level under the finish. I’ve smoothed, cover coated, and sanded my @#$ off with every grit of wet/dry from 800 to 2500… still inconsistent.

I build steel string acoustics with a water based ktm9 finish.

Please, I do not want to get into discussion about the final finish because the final product is only as good as the pore fill/level/color underneath.

I’m thinking about pumice pore filling, but I’m open to any suggestions.. Thanks to all you guys, TonyF

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Tony Flippo

I recently switched to west systems epoxy. I like it and find it is easier to get an even coat.

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ELEVATE || Next Level Lutherie
http://elevatelutherie.com
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http://ensorguitars.com

After I started to use heat, ala a hair dryer, to put on each coat with no thinning I have had no problems, I paint it on with foam brushes , two brushes for each coat , one to apply and one to go back over to smooth and soak up excess zpoxy. The last two I also used 3 coats and allowed at least a full day between coats, my problem has always been just getting all the pores filled which don't seem to show up till I start shooting sealer

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MK5acoustics.com

I preferred System 3 epoxy. No matter what you do, it ain't easy.

Try using Egg Whites. Sand it in using P240 paper. The sanding creates a slurry that fills the pores and dries hard. It's easy to sand level and two applications should do it.
Mat

Crystalac is a water based product that I have tried a few times. You do have to put down a good few coats of sealer before you use it. It sands easy and fills nice. If you sand through the seal coats, it can give you light and dark spots if you are using IRW. I have used 3 coats of a spray can "Watco" lacquer to seal. Sand it down to 300. Give it 1 more lacquer coat. Then pore fill 2 times with a plastic scraper. Let dry and wet sand to 500-600 black paper. You have to light sand it. If you sand down to far, you will hit bare wood and you will get lighter areas. Pore filling mostly sucks and there isn't any real easy way unless the chinease that made my amish kitchen table would like to let us know what they used to seal it. Some secret clear stuff that might be full of lead or something.

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Jason Moe
LaCrosse WI 54601

My favourite (at least in terms of looks) is the Oil sand fill. very similar to using the egg whites but using a thin Oil varnish. I then French polish or Spirit varnish over it. In terms of actual working time it's pretty quick. In terms of drying time it's fairly long - two 'coats' over a period of 8 or 9 days or so. The stuff has to be more in the pores, rather than sitting on the surface. It also needs to be thoroughly dry before putting another finish type on top. It's the Oil that displays the grain better (IMO) than putting straight Shellac directly on to wood. Occasionally you see French Polishers applying Linseed Oil directly on to wood before continuing with the usual polishing process. Not quite the same but it has something in common with that.
The Pumice method is quicker but the working time is very similar. Perhaps you should prepare a few open grained boards and try filling them side by side to see which method you prefer. Pumice, Egg Whites, Epoxy, Oil sand and a water based filler can all be tried.

Haven't yet pore filled a guitar. I'm only on number 8; not trying to sell them, just giving them away to family and friends. I do French polish so I have some pumice ready, if the mood hits me. I've used epoxy for a couple of kayaks, and seems like it should work especially if you squeegee it in, but I'm afraid of all the sanding that would be required if you leave any behind. The egg white approach sounds interesting, and more in line with low tech finishing method. Right now I'm working on a padauk guitar (has some decent size pores), but I'm inclined not to fill these either. Seems like a desire (or maybe a requirement from buyers) for a mirror smooth finish leads to lots of angst that I've fully avoided thus far. Ignorance is , I guess.

If you are looking for easy, send your guitars out. Other than that it's work. The brand of epoxy doesn't matter much from the work aspect. A pumice fill is every bit the work of an epoxy fill, it's basically sanding until the pores are full. And shellac can be problematic under WB finish systems.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Once I started using egg whites I never looked back. I know you don't want to discuss the final finish product and I agree that the final finish is only as good as the foundation you lay it on but... I gave up on KTM too because of the inconsistency. Ok that's all

I tried eggwhites and it dried white in the pores. Getting close to pore finishing 1 now and dreading it! So far I have used pumice and it is my nightmare least favorite part of guitar building. Pumice takes finesse and practice. Strangely enough my first came out great and the rest (I am on #6) have been extremely frustrating. Thinking about trying epoxy this time but this discussion has me giving it 2nd thoughts.

West System 105/207, three coats, sanding only with 220 in between, drop fill any problem areas. Each sanding session is no more than 20 minutes total. I will use a scraper to initially knock down any areas of excessive buildup. Purple 3M rubbing pad quickly eliminates any shiny spots for better adhesion of subsequent coat. I've done 7 guitars this way, am very pleased with results and plan to stick with the approach.

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Doug

Don't let fear or common sense stop you from trying to build something

I settled on System 3 epoxy, 2 coats on the back and sides. And a pro-line traditional oil based filler from Sherwin Williams on the neck. Best combination I've found after trying just about everything else.

I use shellac/everclear and end grain rosewood sanding dust rubbed in with a cotton ball per Robbie O'Brien's online course.
Takes a while but smells good and is relaxing to do while listening to music or watching tv.

Z-poxy has worked pretty good for me... maybe just dumb luck... I apply with an old credit (type) card, usually about three sessions with sanding in between. I don't go through to the wood, just level the surface....

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

For those of you who use epoxy do you sand back to bare wood or do you actually leave a coat on? With a traditional filler you want to fill the holes and then sand back and if necessary fill again but you always sand back to where the holes are filled and level but everything else is bare wood right? So I wonder if perhaps taht is the problem flippo is having? Or is that normal?

+1 on the egg whites!
Wendy, when I fill with egg whites, I sand them in with 320 p graded sand paper, it takes on the color of the surrounding wood, so it won't dry white.

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Jim Watts
http://jameswattsguitars.com

I'm old school and still use tinted oil-based paste wood pore filler.

I have mostly used the pumice method. It works, but it is slow and often frustrating. If I do another pore filling job with pumice, I will do my best to focus on the idea of the sawdust, mixed with the shellac from the wash coat (both created by the sanding action of the pumice and alcohol), being what really fills the pores. I have in the past thought that pumice was the major ingredient filling those little holes, and tried to accomplish more filling by using more pumice, but I now feel that was a mistake. I now think that the overuse of pumice contributes to white pores. I now think that the pumice is mainly meant to just be the abrasive that creates the filling material, not the filling material itself. This may all be self-evident to most folks who do French polishes, but it has taken me a while to come around. And I may still be off base, but I think this is progress. We'll see.

I recently tried Timbermate. It was super easy and fast, but I am seeing some sinking, so maybe I did not let it dry long enough before sanding back.

I am super intrigued by the egg white method. Could those of you who favor egg whites post some photos of your finishes? If I could get that to work, I would drop the pumice method like a messy diaper.

Am I the only one who likes CA as a pore filler?
I use the thin CA, wiped on and spread around with a plastic card, then sand back to bare wood.
One application usually does it.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I'm about to suck it up and give UV cure a try. I'm currently using Zpoxy and EM6000. This system takes way too long, plus the shrink back 3-6 months later. Going from pore filler to buff in a day is very appealing! Yes, $2-3k for the gear is a major hit, but hey, what can I say, I'm a tool junky!

Cheers, M

I tried it and I agree, it worked great... in fact, I thought I had found the answer, but I could not handle the fumes. I tried respirators, fans, etc. My eyes were killing me.



With epoxy, I never sand back to raw wood. I just level the epoxy. Helps to work it well when applying so there aren't many ridges and nibs to sand down.
When using traditional oil based filler, I never sand after applying. I let it flash dry and rub off the excess with burlap. Yep, burlap, no rags or towels. If timed right, the burlap (which you can get at Sherwin Williams) will remove the dried filler from the smooth wood and leave the filler in the pores. With soft rags, you'll have to rub so hard you end up pulling it out of pores.

This used to be about the time Todd Stock would chime in. Well, perhaps earlier. Sanding back to wood almost always reintroduces "new" pores. Yet how to level sand without doing that? More initial coats is all I can figure. Plus, you have to use that squeegee Todd is always talking about. I bought several at Lowes. Cut them to different sizes. With the grain, across the grain, diagaonal to grain. Anything to to get the stuff down in the pores. Lots of this early on insures a good pore fill. No matter what you do, it's hard and tedious work. And messy and potentially bad for you. Maybe one day someone will invent the perfect solution. But given how long the quest has been going, I'm kind of doubting it. I like the hair dryer idea... just surprised it does not accelerate the reaction.

Mike

I think most of the problem is folk trying to fill pores too fast, in one sitting. If you plan for two or three separate sessions (with drying/shrink time between) it usually goes a lot better. Pore filling doesn't take that long. The Pumice fill I can do in 3 X 10 to 15 minute sessions for Back/Sides. Same (or less) with the Egg White or the Oil Sand. The pumice method requires no (or very little) sanding. Somewhere I came across a guy who said it took him the best part of a day to pumice fill, meaning that was the working time! It may also take me that long if I didn't allow the stuff to dry, harden and shrink between applications.

Working outside with a fan behind you is almost necessary. I've also used older CA, it doesn't cure quite as fast and the fumes are not nearly as strong. I wouldn't trust it for a structural joint, but it works fine to fill pores.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon