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Hi all,

I have been looking at the info that is out there regarding pore filling, usually with epoxy or some kind of paste, but most instructions and tutorials I have seen seem to focus on the back/sides. Probably because it looks cooler in the pictures. I haven't seen any that talk about the top, but nothing has explicitly said not to do it.

Any thoughts?

adam

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"Everyone wants to BE something, but nobody wants to BECOME something" - William Cumpiano

most top materials dont require filling.

So you just lacquer right onto the top? Any kind of sanding sealer or anything? Or is it desirable to have the grooves from the grain feelable (is that a word?) in the finish for the top?

Thanks!

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"Everyone wants to BE something, but nobody wants to BECOME something" - William Cumpiano

the purpose of filling the back and sides is to fill 'open pored' wood ( such as mahogany or rosewood) to provide a smooth level surface over which your finish will be applied .
If you are using spruce as a top then it isn't necessary since it isn't open pored.

Some back and side woods, maple as an example, do not need pore filling either.

I have used paste wood filler for over 25 years, and have only recently switched over to Z-poxy..
In my opinion it is much easier to apply and looks better... doesn't have the sometimes 'muddy' appearance that paste wood filler sometimes does; addition to that, there is a great tutorial by Hesh Breakstone here on the OLF.. It would be well worth your time and attention to check it out.
best regards,
jack

Thanks, Jack! I actually checked that out and as it didn't mention the top, it caused me to wonder if it was left out because the process was the same, or because you aren't supposed to do it.

I think the consensus appears to be not to do it, so that's what i'll go with.

Thanks again,

adam

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"Everyone wants to BE something, but nobody wants to BECOME something" - William Cumpiano

you can also use z-poxy on a figured top or other figured woods (maple bindings) to help pop the figure. You do a diluted thin wash coat.

I've found that spruce straight from the sand paper can have too much texture to get a flat finish on, at least with very thin french polish. It might be especially bad with perfectly quartersawn wood (Shane... ) which tends to have quite a texture after sanding. So you need to do a couple grain raising sessions with a damp cloth or with egg white. A bit later when it gets dry (do not flood the thing just barely damp the surface with a damp cloth or a fine brush and eggwhite) fine-sand the raised ridges. A second application and Bob is your uncle.

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Build log

Adam: Have filled tops with a diluted coat of epoxy thined with alcohol. It helps to fill wooden rosettes and also lets you build faster with nitro. Have also finished with just the nitro and had success,drop filling any pores in the rosette. Dont think its too much to worry about and am sure either way will work out.

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A person who has never made a mistake has never made anything!!!

Personal opinion Spruce, redwood or Cedar tops should not be filled even with a diluted epoxy, though i have don it before. You just add to the damping of the tops responce when you fill or seal as it were with epoxy. Spruce I always size with egg whites. This will stiffen the outer fibers a good deal. it will aso cause those fibers to raise some after the sizing dries I lightly sand back with 220p and seal with shellac but I use shellac to seal everything prior to applying a sprayed finish. Shellac is the least dampening sealer or finish you can apply to the top.

I was wondering about the damping as well when using hardwood tops like mahogany, walnut, koa, or spanish cedar. Is there a pore filler that's preferable to the others with regards to damping (e.g., is pumice better than CA or epoxy)?

cheers, Christian

I do not fill any spruce. You can use a sizing which egg whites are . Sanding sealer will do the job nicely , that is what it is designed for. No need to make it harder than it has to . If you are French Polishing , the wet sanding should get you level. Use 320 and go across the grain. That is a trick I learned from Frank Ford. This levels the top very well.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I personally like it when the top finish is ridgy with the hard winter growth, i think it looks nice, and it is an indication that the finish is probably not too thick.

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Jordan Aceto
Ithaca, NY

Hi Adam. I used a thin coat of diluted zpoxy (50%) denatured alcohol on my last two tops because I wanted to add a little amber tint to the top. Otherwise, I've been using clear shellac as a sealer coat. BTW, are you the fellow that bought my HD28 a couple years back?

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Ron

Hey Ron,
Yep that's me and I still can't believe my luck every time I open the case. Thanks!

adam

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"Everyone wants to BE something, but nobody wants to BECOME something" - William Cumpiano