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Seems like the way to go. Any drawbacks to this method that I might be missing?

https://www.youtube.com/watch?v=1MLVfjwNsEM

Nice link. One of the guys who inspired me to build to begin with, Tom Morgan, used to finish his guitars and mandolins with epoxy alone. The epoxy produced a nice thin finish that was acoustically transparent, but I never liked the final look that well.

I've done many instruments using Tru Oil, but I haven't combined the two finishes the way that Ken does. Tru OIl really can get any kind of sheen you want from satin to super glossy, depending on how many coats you apply. I first started using it after reading the oil finishes for guitars article in the old LMI catalog, The downside has always been that the surface has to be sanded to super fine grits before applying the oil or every little scratch will show. The epoxy base coat would seem to me to eliminate that issue. I'll have to give it a shot sometime.

Dave

I used zpoxy on my archtop, I added a tiny speck of oil paint to the finish coat to warm up the color, and it worked good. I thought of using his method on the guitar I'm making now. Ken has a lot of ideas I'd like to try.

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Why be normal?

As far as I can tell, Parker is using the epoxy as base coat and to enhance the figure in his wood. I have been using Zpoxy for both those functions - sometimes simultaneously, sometimes just one or the other. Parker scrubs every bit off leaving only what has been absorbed by the wood - I've been leaving mine a bit thicker and trying to sand back level. I'm pretty sure I will be trying his method next thing I build.

I've admired Ken's thoughts and designs for quite some time. He's truly a critical thinker, willing to explore and try new things while still applying old school respect for tools and methods.

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"Act your age, not your shoe size" - Prince

Yeah, I really like this idea of not having to sand back, but he replies to someone's question in the comments section about pore-filling and he says he does not do it. Still may try it, though. Seems about as hassle free as you can get.

And, yes, he does sand up to 1500 - as per the comments section: "Carborundum EZ Touch Micro Fine "P1500 - P1200""

And Chris, you are spot on. It's really cool to see him responding to people's suggestions in the comment's section. Very open-minded and it looks like he going to be uploading (in time) the entire build process. Anyone interested can start here: https://www.youtube.com/watch?v=snzCzLhr4vg

It’s something I might try on my next guitar. I used egg whites on my last guitar. I was quite pleased with the outcome, but this seems like an easier process - one coat and you’re done. I use west system epoxy a lot in furniture making when I need a long work time. They make a fast hardener and a slow one. In the summer, the fast hardener will only give you a few minutes work time so I switch to the slow hardener, but in the winter it’s the opposite. It’s good to have both hardeners handy.

If you thin the epoxy 10-20% with alcohol you can apply the epoxy in a "French polish" method - rubbing on a thin coat, and avoid most of the time wiping off excess epoxy.

But Ken Parker doesn't fill the pores. He uses Z-poxy to 'pop' the figure and seal them.
The chestnut doesn't have a flat finish at the end, which is what most people use a pore filler for.
You can see that in the last video.

Actually, he’s NOT using Zpoxy, but rather West System. There is a world of difference. ZPoxy is very fast hardening — you need to work quickly to remove the product before it begins to set. I didn’t watch the whole video, so can’t say exactly which hardener he was using. West System has four. He referred to a slight amber colour and 5:1 ratio, which lead me to believe he was not using the 207, which is very clear and intended for finishing. Compared to zpoxy, you have oodles of time to work the product, without resorting to alcohol or other thinners.
For those thinking of applying Tru-Oil over epoxy, you’ll want to read up on “amine blush”. At the very least, you’ll want a few coats of shellac as a barrier between epoxy and any oil varnish.


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Using epoxy to pop the figure will somewhat fill the pores whether intentionally done or not. "Wetting out" the surface is necessary to pop the figure which will cause the epoxy to sink into the pores. On open grained woods, that may not completely fill the pores, which is one reason those who epoxy pore fill often do more than one coat. On close grained woods a single coat of thinned epoxy might be enough.
Ken was using the same epoxy I use (West system), but there are several epoxies on the market that will work well, as he mentions. I have had the 207 turn dark red when it gets old (but still works fine) and amber the mix a little. He was using 5 to 1 ratio epoxy to hardener (as Tim mentioned), so probably "normal" 205 or "slow set" 206 hardener.

Interesting. You prompted me to have a look at some 6-year-old 207 on my shelf, which has indeed started to turn colour, although not nearly as dark as the 206 or Zpoxy I've used. I guess we just need to use it faster!

Those are great videos, one thing that was almost glossed over but Ken did mention briefly was that he wipes the epoxy off with water before moving on to the next step in order to remove the amines. This is critical for most epoxies or you will have issues down the road.

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Jim Watts
http://jameswattsguitars.com

Yes, Jim. I should have mentioned this in my first post- one really needs to watch all six videos to understand the process, and he does talk throughout the videos as it's all in real time. Also, he answers a lot of questions in the comments section.

It certainly is a thin finish that's for sure. I don't see how that technique would fill pores though unless you did several epoxy coats. I'm not a big fan of using epoxy for a finish but I'm also not one to argue with a master luthier too. That guitar is simply stunning.

Funny too how Tru-Oil seems to be the go to finish for beginners. Like it's easy to use and quick so it's good for student luthier and so on. And an experienced or master lutheir wouldn't even think of using such a noob finish. I used it on one guitar and I wonder why I don't use it on every guitar because of those very reasons, it's easy, quick and it looks great.

Sorry, yes, he's using West System. It's just that so many people mentioned Z-poxy I think it stuck in my head.
But I don 't find Z-poxy hardens all that quickly. It's all I've used for pore filling and I've never found it a problem.
Although we are talking about the Finishing Resin aren't we, not the adhesive?

Ken is using the adhesive, not finishing resin, which is why he wipes it down with water before applying True-Oil.

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Jim Watts
http://jameswattsguitars.com

Really? I shot acrylic lacquer for decades before trying TruOil in the early 2000's.... Master gun makers have been using it for decades, and they aren't noobs, either. I used Watco for a long time, too.

Ease of use doesn't make it a noob finish.

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"Act your age, not your shoe size" - Prince

I totally agree, I'm just reporting what I've heard over the years. That Tru-oil is fine for a beginners project but not for ones for paying customers.

I grain fill often with WEST. I know that Ken is not using it to grain fill, but I'd always be using the 207 for surfaces (3:1 mix) rather than 205 or 206 (laminating, 5:1 mix). 206 wet sanded (is that enough of a wash?) can still bloom years down the track, a problem 207 fixes and not one I've ever had with 207. And yes, 207 goes progressively more amber the older it gets (the more oxygen it sees?). Oldish containers just opened are pretty clear. Ken also said it hardens up in ~6-7 hours at ~70F. My shop is often 30+ C and I leave it a minimum of 36 hours before overcoating with nitro. Overcoating too early seems to result in less transparency to the finish when looked at really closely.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

If the epoxy sealer coat is used on a spruce top, for an acoustic, can the area for gluing the bridge be chemically stripped? Which stripper works for that?
Also, when using the epoxy sealer coat over non-wood bindings, is there an adhesion issue with any of these bindings?

James it would probably be easier to just scrape back the finish to bare wood with a chisel as a scraper then use a chem stripper.

Tape it off before applying any finish. He’s wiping it so clean that I doubt removing the masking would be any issue at all


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I use West with the 207 hardener and I also add silica to thicken (the consistency of mayonnaise). The epoxy does not penetrate much at all on spruce at this consistency -- very light sanding with 220 grit will remove the epoxy -- so as long as you prep the bridge joint by sanding before gluing, you won't have any adhesion issues at all.

Easiest to use a mask. I generally use frisket film, but tape will work. Scribe carefully around the edge after finish and lift it off. Then your bridge glues to clean wood.


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