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I've never really done it. I sealed with a few coats of Zpoxy, and then a finish coat, but it wasn't pore fill, and it takes so long to dry, and it's cold again in the basement.

Recently several said that they liked aqua coat. I'd just go with that, but I have a gift card for StewMac; is their color tone clear any good? Has anyone used it?

It does say to seal first, which is no bother, but it also says to use above 60 degrees. I'd have to do it upstairs. Does the aqua clear have temperature constraints?

Some reviews said that the StewMac product wasn't really clear, deep holes could be white. Who needs that?

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I don't have any experience with the SM stuff but the Aqua Coat is really quite good. I would recommend you get that and spend money elsewhere on SM.

I'll tell ya what works great is CA. It works amazingly well. Though you will need ventilation unless perhaps you use the odorless stuff.

I have used CA on fingerboards, and it works great for that. This Padauk is pretty porous; it would probably run right through! On a fingerboard it is fast enough so I do it and hang it outside. A body? Seems like a lot of work, and a lot of CA.

Thanks for the recommendation.

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I like Aqua Coat too. Their website recommends 60-85 degrees "ideally," though I've seen posts out on the web of people using it at lower temps without problems. I know it works fine at 60 or so.

Dave

I actually DO pore fill with Zpoxy and I love the stuff. Usually two full strength coats applied with a plastic card, then maybe one or two very dilute coats for grain enhancement if needed. I have never had trouble with it not curing, but I've also never applied it when it was really cold.

A long time ago I did do a three way comparison between the old StewMac paste, Zpoxy and CA. The paste was fine on wood that didn't have a lot of character or figure, say mahogany necks. Zpoxy was hands down the winner if the wood was figured (and I frequently use it on non porous wood just to pop figure). It turns out that I am hyper allergic to CA - if I tried to do a body it would probably kill me.

You might consider SystemThree SilverTip epoxy with their Fast Hardener. I pore filled with Z-poxy for several years and was happy with it. I tried SilverTip for the first time last year and have switched over to using it for pore filling. The advantages as I see it over Z-poxy are faster hardening, much lower minimum application temperature (35 degrees F), and it doesn't smell like it wants to kill you. It's also clear where Z-poxy has a light amber tint. That's either a pro or con depending on what you are looking for. It also has the qualities that I liked about Z-poxy. One person I know who has used SilverTip longer than me has observed that it doesn't shrink back like Z-poxy does. My experience so far bears that out.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I'm using all Crystalac products at the moment and their pour filler works pretty well, though I need a few coats to fill some pourus woods like EIR and cocobolo.

Another vote for Silver Tip, if you are going to use an epoxy.

Everyone has jumped in here with their preferred and proven methods of pore filling. They probably all do the job. But I do need to ask the question of why we all feel the need to fill pores in the first place. Do we need a piece of wood to look smooth and glossy like glass?

If you are building a guitar just for yourself, or for someone who is OK with how the guitar will look if you don’t fill the pores, then no, you don’t have to fill the pores. If you are building a guitar for most folks who want to own a fine handmade guitar, they expect to see a smooth, glossy finish.

I have built a couple that I can remember over the last 25 years where the client wanted no pore fill. Otherwise it's expected. I personally think it looks better myself too. The unfilled pore look sort of detracts the eye from seeing the whole wood panel in all its beauty. But to each their own of course.

As for CA, I have used both Aqua Coat and CA and found the CA to fill a lot faster and even easier then aqua coat. But the AC is good stuff and doesn't stink. CA has to be done in ventilation. I do it outside.

As far as filling goes, I've never had wood that absolutely needs it, this does. It's actually for a violin first, and then a guitar from the same board that isn't as far along. I'm sure that if I filled the inside of the back with water it would seep through. I did try my ground coat, and one coat of varnish and it isn't terrible, at least on a violin, but filling would be better. I'll put a photo in.

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Absolutely. Unfilled pores are mfg way of selling guitars cheaply. Those that can't afford a quality guitar will migrate to these and learn to love it because it's all they can afford. It's still a quality guitar in all other aspects I think just not much to look at and run your hands across. I obviously wouldn't buy one or build one.

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Hutch

Get the heck off the couch and go build a guitar!!!!

A discussion of pore filling should include at least one old luthier mentioning traditional oil-based paste wood pore filler. I have also used epoxy and Aqua-Coat, both of which work well. But I also use the old stuff when I want a traditional look. Nothing brings out the beauty of the grain of a mahogany neck like dark brown paste pore filler.

This is what the violin looks like. It would take a lot of varnish/ground to fill that. It's not as bad as I was thinking, but nothing like maple. Even bigger, deeper pores than the walnut violin I did. I still need to polish that one up. The sun is bright today, and I can actually see it good! All the flaws. I'll have to scrape the edges more, the rest is pretty good. I usually don't sand anything except after varnish and fingerboards/neck.

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Yep, those are open pores.

Ken,
Not doubting your explanation of open pores on the violin but the picture sure looks like something other than cellular pores....perhaps some kind of insect damage.

No Tom, it's just a closeup. It's nicely quartered, and the vertical pores can make lines. The color is somewhere between the two, depending on the light. With varnish the flame shows up too.

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Yep, the new pic is pretty self explanatory.

I have used just plain CA (gluboost) to pore fill on repairs like a backstrap overlay.

What I do on stuff I'm building though is a shellac/french polish pore fill. I sand with some high grit to make some dust and then do a seal coat of 1/4lb cut shellac with the dust still in the pores. Once I've done a couple of passes I'll up the grit (800 or something) and then do 10-12 more passes. Doing this even 2 or 3 times takes hardly any time at all since the shellac dries so quickly. If you use a stiffer medium for your application pad it doesn't pick up the dust and instead seals into the pores better in my experience. I guess you could keep going with that until the pores are just totally filled up and you get a perfectly smooth look. I do it enough to fill them somewhat but I leave a little bit of them visible in order to keep the look really organic. On a mahogany neck I've found that this makes the feel of the neck almost like raw wood even with a good bit of finish applied.

Not for everyone but it's worked for me so far.

If I use mahogany I always use the oil based stuff. I agree nothing looks better. I use it on mahogany necks even if I use something else for a rosewood body.


What kind of wood is that Ken?

It is quarter sawn Padauk. It isn't that heavy, I measured it at .65sg. I don't have enough to make another small guitar; unless I had Venetian cutouts on both sides! It isn't quite long enough for the ribs; I don't think. I cut all that out of about 33" and there is only about 28" left. I used my big ryoba saw; it cuts pretty good. I do have another 6" wide board of dark red/brown Padauk that is about 2" thick I think. That might be good to have sliced.
The wood seems very resonant.

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