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Chris,
I just finished a guitar for the 5th time, and used zpoxy on all of them. This one had Koa as back and sides. I used to used the old credit card way to squeegee off, but got sick of that as it took too long. Now, I just apply with the credit card and smash into the pores as much as I can while working small areas. Then after the all the areas are filled, I take one of those thick blue paper towels and just wipe the zpoxy off so there are no ridges at all. Try to remove as much as you possibly can. Then I sand back to bare wood. It's okay to have splotch marks at this time if you don't get it all off. I've done 2 coats in a day before and had no problems with it drying in time. The key was to wipe off as much as you could. This way you could get 4 coats on in 2 days. The back only needed 2 coats and then a wash coat of 50/50 poxy/alcohol. The sides I needed 4 coats, then a wipe of 50/50.

Also, for the zpoxy, there is a shelf life from what I found. I tried doing a guitar last year and the zpoxy would just not harden. I then bought a new bottle from LMI, and it hardened in about 6 hours. My bottle was about 3 years old, so I'm sure there is a shelf life. I'd give it about 2 years from my experience.

Also, when I mix the epoxy, I use one of those little plastic measuring cups that you can buy bulk from lee valley. I always add a touch more of the hardener. I think this helps with the finish drying faster. Hope that helps.
Tracy

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Tracy
http://www.luthiersuppliers.com

I used Zpoxy for the first time a few months ago. I warmed it up in hot water before mixing. It flowed thin and smooth, and squeegeed off easily. Filled the pores great, and sanded to wood easy. I'm sold on warming it first.

Bob

Hear hear! I have become overly sensitive to Zpoxy sanding dust this past year. I always think "Bah, this little bit won't bother me" and sure enough, within an hour I'm wishing I would've donned the respirator.

I dont know for zpoxy becouse I use epoxy from this co.( http://www.r-g.de ) and in their manual writte:

"Adding more hardener than specified does not result in faster curing, but poor properties. Likewise the processing time cannot be extended when less hardener is added. On greater deviations the mixture may fail to cure!"

Fric

I can't help you with your technique. I've never used Z-poxy. When I use West Systems I sand it all the way back to the wood.

Re, reaction to cured epoxy. I've gotten a rash from sanding epoxy before. I've found it doesn't happen if I let it cure long enough. I'd suggest a minimum of 24 hours, but 36-48 is better. Always were breathing protection when sanding.

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I didn't mean to say it, but I meant what I said.
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Now THAT is golden advice. I will add that you should not wear the same dusty cloths from the last session to finish the sanding job, fresh clobber every session and you should keep a fan blowing the fumes away from you at all times during mixing, and application. It is also worth considering that some epoxy products have less toxic hardeners than Zpoxy. I believe that West Systems, a long time player in the epoxy game, actively formulate 'some' of their products to reduce exposure for the user to what can be the absolutely devastating effects of epoxy contact dermatitis.

I guess one needs to ask themselves if they are in this for the long term and then make an informed decision about which epoxy product is best suited to them. But be careful, I can tell you first hand that this is real nasty stuff your fooling with. You may also wish to google "Epoxy Amine Blush" before you decide that epoxy laid under a finish is worth the trouble. There is no doubt it can be, and there are many examples where it has worked really well. But be warned, should the environment not work in your favour during application, particularly when using anything with natural driers such as any of the oils or varnishes as a finish, then it can be a heartbreak you just won't discover until a few weeks after you have polished out that beautiful finish and it begins to soften and go tacky on you.

Do your research because all finishing methods have their pros and cons.

Cheers

Kim

I guess everyone has their own ideas to what is the key to making this work. From my experience on my last guitar, I have decided the key was to really pay attention to getting rid of any ridges to minimize the amount of sanding required between coats. Notice how careful Todd is about this in his videos. I was going batty introducing new pores each time I sanded but things got better once I smoothed out more during application and sanded less during leveling.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

I use West and squeegee it, then let it sit for maybe a half hour and sort of French Polish it with an alcohol-soaked rag to get rid of the high spots. Still requires sanding and usually 2 applications on walnut.

There just really isn't any fun way to pore fill is there?

Nope

Like Hesh said work it into the pores and sqeege off the access. Keep in mind the intent hers is to fill the pores, not to apply an epoxy finish. In fack I always sand bck JUST to the wood surface the do a very light 60%/40% Zpoxy/alcohol wipe to even the color pop. The biggest errors I seen made is appling too thick in the wrong direction and too light of pressure and leaving on too much film thickness. Tt also helps draw the epozy into the pores if you warm the surface first. you want to work at 45 degree ange to the grain orientation. going with the gran will tend to pull the epoxy out of the pores due to build up in surface tention.

applying Zpozy as a thin coat means the Zpoxy will likely at first bridge the pores due to surface tension then sink partially slightly back into the pores as it cures leaving the pores partially filled. You really need to work it into the pores at a angle say 45% approx. Here again heating the surface first helps to draw the Zpoxy in to the pores you need no more left behind than what it takes to fill the pores. It is impossible to get all the excess off but get as much as you can off. once cured and all pores are fully filled sand back just to the wood and then wipe with a 60%/40% mix very lightly just to wet the wood and have even color pop. if you try to leave much of a thickness at all on the surface it makes things harder to level.

Boy, there sure are a lot of contrary technics with this stuff.

I have used two coats of z-poxy, squeegeed on with a credit card on EIR B&S. Sanded back to wood after each coat . The sanding sucks but is required. 1 year later both guitars show no pores. I sprayed a vinyl sealer and many coats of nitro over same. I am more than happy with the finish.
John

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John Nowicki

Looks filled to me.
I caught that you used Zpoxy in the "what's in you shop " discussion too. It actually my me lean to giving it try.
I've tried 4 different ways and this is the 5th way of pore filling. I'm trying to figure out which I like the best. Or maybe which is suited best for certain builds. Don't know if you don't try.

I've built 26 using Zpoxy as the filler and had 26 successes, love the stuff.............
Mikey

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The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!