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That's a good way to put it, Mike.

Another benefit, I believe, is that the epoxy is applied at a low viscosity and allowed to sit for quite a while, giving it more time to seep into pores and displace the air in them, which mean no (or very few) air pockets that will open up upon sanding. The way I see it, however the epoxy is applied, it is going to quickly fill up most of the pores, but will continue to slowly find it's way into smaller pores, nooks, crannies, damaged wood fibers, etc., and that process will continue whether the excess epoxy is squeegeed off right away, or left to gel first. If squeegeed off quickly, there will likely be open pores after cure, especially if the "squeegeer" does a good job removing the excess epoxy, leaving little to displace any remaining air that find its way to the surface after squeegeeing. By waiting until the epoxy becomes semi-solid you're giving it a LOT more time to find those remaining air pockets and fill them. Also, I wouldn't be surprised if allowing the epoxy to sit until it gels reduces the likelihood of "splotchiness" after sanding since the epoxy has a chance to absorb a bit deeper into the wood.

In addition to all of that, I believe removing the semi-solid epoxy with a single-edge razor produces a thinner, smoother surface that requires less prep before applying finish. In the semi-solid state, the epoxy doesn't try to "pull out" of the pores when the razor runs over it...it just stays beautifully flat.

To be honest, I didn't really think about it. I knew I had left a really thin layer of epoxy when I scraped, so I wasn't too worried about leaving too much epoxy under the finish. Instead, I just focused on removing some tiny ridges left by the razor, and achieving a level surface. I don't recall seeing any color variation, and don't see any now under the finish. I did put down a coat of shellac between the epoxy and the lacquer.

I'll pay more attention next time.

We all want the same thing... Filled pores. Some like the color and "popping" effect that epoxy creates. Personally, I would prefer a clear epoxy with no color. Since all I wants is filled pores, a clear, colorless epoxy would be ideal.

Mike

Do you put the first (or only) coat of epoxy directly on to the bare wood or do you seal it first with a shellac coating?

I prefer to do it directly over the bare wood. No worries about delaminations caused by the sealer failing, epoxy sticks to stuff really well on it's own.

_________________
Brian

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

https://www.howardguitarsdelaware.com/

I do one coat. I used to apply it with a squeegee but I found that I (or at least think) get better results if I just rub it on while wearing gloves. Then after I;ve rubbed the whole thing pretty well, I pull of what I can wearing the same pair of gloves. Next I sand back so there is bare wood again...as in I stop as soon as I start getting wood dust.

Just out of curiosity has anyone on here ever tried using knife grade epoxy? It's usually used for mending seems on granite countertops but after making some countertops for an architect about 6 years ago I tried using this stuff on wood. The material I was using at the time was some stuff called paperstone which is basically dimensionally thick high pressure laminate.

Anyways I used this stuff to bond some parts together to make an ADA counter section and it worked great so I decided to try it on wood. I've been using it ever since and I'd highly recommend it. It dries totally clear as long as your build layer is not too thick. For filling deep pits, say over an 8th of an inch it can start to get cloudy. It's a really nice consistency and mixes much like bondo. It can be applied and worked with a putty knife and gives off almost zero odor. The other nice thing is you can buy compatible pigments in a wide range of colors if that's what you're going for.

I've applied lacquer over it and haven't found any compatibility issues though like other epoxies it will alter the color of the wood slightly when compared to wood that's been sanded back down or didn't get epoxy in the first place. Under finish the difference becomes very slight. Anyways, I've gotten it from granite and stone suppliers in my area, it might be worth a look. The brand I've used is Akemi out of Germany.

Hmmm. Interesting. I have been asking for sometime if there was a high viscosity epoxy (almost like wood filler). I've seen those epoxy putty ads. But drying clear is crucial. 1/8" deep holes would let light inside the guitar, so I don't think that is an issue. Thanks for bringing this up. I may give this a whirl. BTW, you will hear the term "finish epoxy" versus other types. Z-Poxy, a type many of us use is a finish epoxy. Apprently, it's not so good as a glue. But somehow, it's ideal for surface finishing. It does work well... but a certain skill level is (and experience) are developed over time to achieve the desired result. Z-Poxy will change the color of the wood.

Mike

John,

Thanks for the info. I checked their site, but I'm not sure exactly what to look for. Can you specify exactly which product you are using? Are you getting it locally or ordering from Germany?

Thanks

If I remember tomorrow I'll try and grab a look at exactly which type I've used. It's possible that they've changed the label slightly since I bought it last. I've bought it twice from a local supplier who specializes in stone supplies.

I'm thinking it's this one though

http://www.akemina.com/en/products/stonerange/adhesive/polyesterbased/knife/list/679/

It's listed as milky but it really doesn't show until it gets pretty thick. The color tubes are here: http://www.akemina.com/en/products/stonerange/adhesive/polyesterbased/cs-bondings/list/2075/

Thanks,

I got a litre of Tenaxa today to try. Interesting, anyway. I think I'll try to get real epoxy instead of poly whatever it is. Seems to have potential though, and cheap at 30$ a liter.
Thanks, you've given me a new thread of experiments at the very least

Tenaxa...fail.

Need to get actual epoxy. On the hunt....

Finally got a chance to look at it today, it's the marmorkitt 1000 platinum. Looks like it's a polyester filler and not technically an epoxy I guess the distinction being that epoxy is for gluing things together and filler is for well, filling. The website lists the color as light honey but you don't really notice that until it gets fairly thick. I'd describe the color as similar to the older system three stuff.

The Tenaxa is poly too. It looks ok dry, but I found the 3-5 minute dry time a bit rushed. Still looking for true epoxy, but it's worth another go...