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Do you guys do things on impulse? I've been known to do that. I just did it just before dinner.

I finally have the edgework smoothed out. Sanded all the bindings. The wood is almost sealed by the z poxy, but there are a few spots that got sanded through, and on the back it sanded through my nice ash water and cherry chip tannin water patina I had on it. The belly still needs a few holes filled in the inlay, so I wanted to get the back done first.

I just rub the warmed epoxy on with my fingers. I do that with varnish too. I guess it's hands on. The light spots looked horrible, so I pulled out a tube of oil paint; got a tiny bit of Azo Green on my finger; and rubbed it in. It was magical. It is a pretty cool glazing technique. The epoxy feels almost dry, and the color just spreads easily.

So I did the entire back and sides. They already had a very thin coat on. The zpoxy spreads, and then seems to spread even more. I'm not used to that yet. It was easy to blend the color in. It still isn't even, but it isn't terrible like it was. The sides aren't as even, but I should do them separately anyway, it is too hard to hold it when it is still wet.

Finally getting done with the prep work.

I haven't decided what to put over it. I'm thinking maybe a French Polish. Do you just go right into that, or do you have to put a sealer of shellac on first? I saw a really good 3 or 4 part video. What do you fill the rag with? What kind of rag; something cotton?

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Why be normal?

I'm thinking I may just finish it up with the Epoxy. Why not? I evened it out some just now with another very thin layer. I should be able to get it smooth.

How do you get a nice finish coat with it? I mean one that still shines. 800 wet/dry makes it satin. I guess you get it smooth and leave it alone. Maybe polish with something?

edit
I have the belly with the color now too. Looks a little blotchy in the photo. I didn't notice it. I'll fix it the next coat.

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Why be normal?

I dig the shape and your "purfling"! Super creative.

rubbing on the epoxy with fingers may not be healthy.

Mike

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Mike Collins

Thanks Blake. I like figuring out how they drew up violins, violas and cellos, and I used the same kind of ratios and ideas for this design.

Mike, Really? Bad stuff in Epoxy? I rub the varnish I cooked myself with my fingers too. It's just natural resins, turpentine, and oil. All natural. Probably not good either eh? I know that the billows of noxious smoke coming off of it while it's cooking can't be good.

What kind of gloves would work? People used those thin gloves at work because we had graphite everywhere. (the company claimed that it was benign, it's just carbon you know) I didn't wear them because my hands sweat like a greased pig in less than a minute in them. Is there any kind that is comfortable? Does coating your hands with powder work?

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Why be normal?

It's a neat looking piece you got there. Epoxy from what I understand has high damping, so that's something to consider when using it as a finish. I've only ever tried it as a filler twice before and I always sanded back to wood. I think I remember reading some other forum a luthier made the comment that epoxy is good for a boat but not on his guitars

Of course a lot of people use it, but as a filler not a finish unless I am mistaken.

Speaking of boats there have been many a boat maker who's careers have been cut short due to the toxicity of epoxy. You will be working along just fine and then one day Bam! You are now allergic to epoxy. They all of a sudden have a sensitivity to epoxy that causes a severe reaction. It has happened to guitar makers too and they don't use nearly as much of the stuff as boat makers.

The finish is very thin. Epoxy spreads very thin. After it spreads, you can even spread it more. Like it thins as it sets.

In a week or so we'll see how it sounds. I have to put frets in, tuner machines, make a tailpiece, and fit and set a bridge. The tailpiece is easy. The tuners should be too. Frets I've only done once, and did them so fast I don't remember. I did a glued on guitar bridge on the 1/2 scale guitar, and the action seemed fine. Maybe I got lucky. I was just trying to get it done before Christmas.

Intonation wasn't bad either, but I don't think I'm that fussy. They are in equal temperament right? Nothing is dead on anyway! Yes, the octaves, fifths and fourths, but string to string, note to note? If you really want it, you have to get it. And how do you go down?

It still sounds like a guitar when you pick it up, and rub it anywhere. It doesn't sound dead.

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Why be normal?

I'm no expert, and people have varying views of this, but for the past few years I have been more aligned with those who believe that it is the thickness of the finish material, rather than which specific finish material used, that has the biggest dampening effect. In other words, the question is not whether you use shellac or nitrocellulose lacquer or polyester or a form of epoxy; the question is how thick it is when you are done. Thicker dampens; thinner lets the wood vibrate more.

I think the choice to put another type of finish on top of a thin layer of epoxy is popular because that other type of finish is more easily buffed to a mirror shine. Epoxy may be a more difficult material from which to produce a glass-like finish.

I definitely agree with the cautions regarding overexposure to epoxy. It is useful stuff, but overexposing yourself to it can lead to problems none of us need in our lives. At least wear nitrile gloves when putting it on a guitar.