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I originally used Pumice to pore fill and then started using Epoxy. I experimented with CA but the fumes almost killed me. Wondering what others do and the reasoning behind why they use the method they use. Pros and Cons of different methods.

Z-Poxy. Just spread a few light coats (depending on porosity) with a credit card and sand smooth. It is slightly amber colored and really pops the grain. I used to use McFadden's oil-based filler...the Z-Poxy is easier, gives a much better appearance and doesn't stain white binding.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Is it really necessory to fill ?

I think it's a cosmetic thing and doesn't do the guitar's sound any favours at all.I know there are builders who don't . Something that plays on my mind as I perform that nasty and (for me ) ,difficult task.
I don't mean to hijack your original thread here Richard, but I would be interested to see what others might add on open pores.
I myself have tryed epoxy, wood dust/shellac, C.A.and paste. Haven't had 100% on any (my inexperience,I know ! ). In my own mind , I don't really feel right about adding these materials to the instrument. Just doesn't add up to me.
Sure would make life easier too !!

KiwiCraig

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CRAIG LAWRENCE of AUSTRALIA
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You don't have to use pore filler. I have used only nitro on both mahogany and rosewood, but if you want to fill the pores completely with it, you need to let it cure for a long time. It will sink in some over time, so it takes many coats and much sanding but the result will be very clear. When the pores start to show again after some years it just adds some patina, not necessarily a bad thing. Nitro cellolose lacquer will not last forever anyways. Necks are easier than sides and backs, the not so perfectly filled pores will be less apparent.

However, I now use Araldite rapid (5 minute) epoxy thinned with alcohol as pore filler. It makes finishing go faster, it is crystal clear and it will not sink in. It does not sand so well, so I scrape most of it off, I want it only in the pores before the first coat of lacquer goes on. I have tried the CA thing, but I could not stand the fumes.

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Rian Gitar og Mandolin

The amount of filler that goes in/onto a piece is really minimal, and dries hard. I can't say I've heard real changes (tapping) before and after grain filling, though.

I've been using StewMac/Targets waterbased filler, works well, sands well, does require 3-4 applications on huge-pore-grained wood. I tend to want the sealer in the pores only, not sitting on the surface, and I'm getting geared up to do a few test panels with System 3 epoxy. I do not, however, pore fill my necks (except for the headstock). Don't see the point to it, and I like the more 'natural' feel. I use shellac or oil as a finish on those anyway, and don't buff them to high gloss.

I don't think un-porefilled wood is going to have significant, or even audible tonal effects. If you want a gloss finish, however, dimpled pores do not look attractive. If you have more of a 'natural', satin sheen, they work just fine. While tone and playability are of utmost importance, cosmetics run a very, very close second (or third).

Of course, you could just stick to woods that don't need filling ;-)

    I use pore o paq . I like this as the color can be added to the filler and I stain at the same time. I do it much like CF Martin.
   First I seal the wood then I fill , Sometimes 2 times to get all the pores filled. Then I seal agian and a light scuffing then start lacquering.
   You can expect to spend allmost as much time finising as you do building
jonh

[QUOTE=tippie53]     I use pore o paq .
jonh[/QUOTE]

Hi John, what is pore o paq? Google did not turn up much.

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Rian Gitar og Mandolin

[QUOTE=Arnt]   what is pore o paq? Google did not turn up much.[/QUOTE]

Try search on Pore-o-pacTomS38690.413125

Arnt, it's made by Behlen...try LMI at www.lmii.com and it's there under the finishing section...I have some unopened cans I'd give you but I don't think they can air ship it (and if they could, who knows what the cost would be?

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http://www.presnallguitars.com

Thanks for the offer, but I'm OK with the epoxy for now! So what's the matter, you don't like it?

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Rian Gitar og Mandolin

I just like the clear epoxy fill for neatness and not having to be so careful with maple or white bindings...also everything in my shop was brown when I got done using the Pore-O-Pac!

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http://www.presnallguitars.com

This is my first guitar. Robbie O'brien's instruction has been a great experience. More on that in a more relevant post.
I used system 3 epoxy. Z-poxy is not available here in any Denver retail outlets (as far as I could find), so instead of waiting for a mail order, I bought system 3. It is a little touchy 1) if you don't mix it right (although I do think there is room for a little error now) and 2) If it is not mixed well. After getting that figured out, it worked beautifully and sanded very easily. It takes epoxy coloring paste very well, and it finishes out like a dream.
I used it in conjunction with KTM-9 with very few problems as a complete rookie. I don't know much about the tonal aspect of it, but aesthetically, I don't see how I can do much better than system 3.
I am trying to get photos up on here. I am having trouble with posting and reflections of the high gloss. How do you take a photo of a high gloss finish anyway?
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

This is the follow up photo posting of the smoothness I got with the system 3 epoxy grain filler. I used the clear coat and not the SB-112. Hope this post turns out well. I'm flyin blind here never having posted a photo before.

Again, this is the first guitar that I have built and there have been many errors, but thanks to a semester with Robbie O'Brien, the result has been better than I could have anticipated when I started this in late August.

On with the show:

No the guitar is not made with the same material as my floor. I just can't figure out how to take a photo of a surface that is this glossy and smooth :)


Again, I just don't know how to take a photo to capture how well the materials allowed me to create a good finish.


The system 3 did pop the grain on this maple pretty well, I think. I may think about staining or using more of a paste based colorant in the epoxy, though, to really get it going.


Overall Front view.


And the back


I still need to set this guitar up with the nut, saddle, etc., so I'll update on that later this week when its playable. As far as looks go, I really don't know if I'd use anything else for the next couple guitars other than system 3 and KTM. (Much to my wife's chigrin, I am cursed with the guitar building bug).

Take care.

-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Top tip for gloss photography: natural light (no flash!) and show the reflection of something (The sky works well).

I don't know how you would get it to thicken, but on my last guitar, which was a mahagony dred, I noticed a partial bottle of Tru-Oil grain filler that had been sitting around for probably 10 years. It was so thick, it wouldn't even pour out of the bottle. I tested it on a piece of scrap and it seemed to work fine. I smeared this mess on the back of the guitar, squeegied it into the pores, let it dry and sanded back. It is probably the best thing I have tried, and I have tried most of them. Fast, excellent fill, easy sanding. I only had enoug to do 1 guitar. Any ideas on how to make this stuff thick?
Jimmie D38691.3733333333

Jimmie

Is that stuff clear?

Josh

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Yea, it was the clear, not the walnut. I think its called Birchwood-Casey gunstock filler and sealer or something like that.

Jimmie D,

The regular Tru-oil varnish will thicken (or "kick" as it's called) with simple exposure to air so you could leave it out in a carefully watched open container & see how long it takes to thicken on it's own. Don't know what's in their grain filler / base coat formula. Is it normally as thick as the varnish? Heck, it will take only about $8 to test this idea using the standard Tru-oil varnish. If I try it I'll let you know the outcome. ("must test on scrap 1st" - repeat this mantra continuously)

Skip

System 3 SB112 with the silica thickener. I really like what it does for the wood grain - it gives the appearance of depth to the finish.

I found these little plastic cups at a local hobby shop that I use to mix up small batches. They have graduations in ounces and ml. on the side. I find that 15ml of epoxy will cover a side. I have never had a batch that would not cure completely.

I also found that the stuff is soluble in denatured alcohol. If I sand through in a spot I will mix it half/half with alcohol and wipe it on with a paper towel. It helps to keep consistent appearance.

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53% of all statistics are made up on the spot
http://driftwoodguitars.blogspot.com/

YOu guys should really see J's guitar in person. It is beautiful and the pics really don't do it justice. YOu would think that J had built many guitars already cause it turned out nice. The attention to detail is excellent

I know some people use silica to thiocken the epoxy others use thinner to thin it (I do the latter with West system) Seems the two methods acheive the same end with different techniques. I tried to use West system once with out thinning and it didn't work as well as when thinned.

I spray a wash coat of catalyzed urethane and then fill with three cats of UFO CA from LMI. I squirt a little on in sections and then spread it with two fingers covered with green lacquer tape. It doesn't fume like normal CA and it seems harder than the epoxy I've used. It sands better,too. It's not what it looks like initially that counts, but what it looks like down the road.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Richard , how did West System sand ? how long did it take to go off? Did you leave a film or go back to wood. I'm interested as it is one epoxy I can obtain here in Australia fairly easy. I tryed 5 min. araldite ond suffered a small nightmare with it's sanding abilities. I have a bit of ripple in my mah. sides which makes it hard to scrape. I got it back to wood in the finish with about a 95% fill
Also Richard, How much alch. do you add ?

Thanks all

KiwiCraig

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CRAIG LAWRENCE of AUSTRALIA
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