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Thanks to all the help of this group I am approaching the final steps of filling the pores with z-poxy but need some help.

1.)Right now I have applied one layer, sanded with 320 grit and applied another layer. The wood now has that "finished" look to it. Their are some streaks but I will sand those down with 320. Question: Do I sand all the way back to the wood so it looses its finished look and returns to the original color or am I just sanding to level now?

2.)Trying to stay a step ahead,I tried the final layer on a scrap. I mixed the zpoxy with 50% DA and wiped on with a cloth. There were some cloth marks and tiny bubbles/dust spots so I sanded with 400 grit sandpaper. The surface lost its luster and has tiny specs of discoloration now. Is this how I finish off the final layer or am I supposed to do something else before I spray?

Thanks!

turbo41139033.8068171296

Turbo, you have to make sure the whole surface is covered by the epoxie... you can do that by applying the thinned epoxie with a paper towel or a rag. If any areas get down to bear wood, it'll look like a stain under the finish.peterm39033.8115046296

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

sand all the body just to wood do not stay in one place too long. Sand just to the wood and move on. once you are at wood everywhere mix a batch of 60% Alcohol 40% Zpoxy and apply will a soft cotton lint free cloth. this will give the finished color back but leave no film thickness. You want to remove any epoxy film thickness left on the surface then wipe with the 60/40 mix if any film thickness to speak of is left on the body it will appear different depending on the thickness of the epoxy film in specific areas. When yo apply finish this difference in depth is very apparent. That is why you need to remove all the epoxy film from the surface leaving only in the pores then do the 60/40 mix wipe will even the color every where.MichaelP39033.820787037

Thanks for the replies. What grit sandpaper do I use to sand it down to the wood before the 60/40 coat?


Then after the 60/40 coat what grit do I use? What should it look like at this point on my sample piece when I sanded with 400 there were tiny circles where the color was different?turbo41139033.8609375

Try hand sanding with 400 and you'll be fine. It'll just take a few minutes.

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Jim Watts
http://jameswattsguitars.com

I found that out too when I used an old cloth on my test piece :)

Are we saying I should sand back to the wood with 400 or sand the 60/40 level with epoxy or both?

My view is still when you've sanded back to the wood and the pores are filled, then it's time to put the epoxy away and get out the proper finishes. Preferably French Polish!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I have done it both ways but Agree with Colin, sand back to wood and then french polish. WFM

The problem I saw when I sanded all the way back to the wood was that it looked splotchy even with the "wet" look removed. Have I sanded too far?

I thought the 60/40 mix was to even the color. turbo41139034.4518287037

I don't mean to hijack but is it the z-poxy that is more forgiving on the mix ratio? What I think I heard was that z-poxy was a 50/50 mix and the West Systems was more touchy. Any comments? Has it been easy to use turbo? Post some pics of your progress if you can so we can see what you are getting.

Donovan,

I found some small plastic mixing cups at a local hobby shop that make the process easier. They have graduations on the side and make it easy to mix a batch as small as 15ml. That seems to be about the right amount for a single application.

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

You are correct, zpoxy is more forgiving and mixed by eyeballing.I haven't had any problem applying or mixing and it seems to fill the pores well. The only problem I have had to date is how to finish off the zpoxy step before moving on to the nitro phase. Apparently you sand back the glossy zpoxy layer so just the pores are filled and then some say to spread a final thin layer of part zpoxy and part denature alcohol. I'm just having trouble with how far to actually sand back to and what grit sandpaper to use

Not sure why you would say West System is touchy to mix. I used used it for
many years and with the pump system it is a no-brainer. I have never had it
fail to set properly, even with a one squirt mix.

Not sure about the west systems, but System 3 is sorta touchy. Its measured 2:1 by weight, so a small gram scale is critical. Mixing it thoroughly is key as well.
The System 3 clear coat is water white, though, so if your finish is very clear as well, it may be a little dull in color, so I add a slight tint of amber to the epoxy.
I used Z-Poxy on my last one and I was pretty happy with it. Its amber color is really nice. Especially under KTM-9.
-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

Thanks guys. I guess that it was the System 3 I had heard was "touchy" about the mix ratio. For me, if the zpoxy works well and the mix ratio is simple (doesn't need a scale), it becomes a no brainer. Again sorry to hijack the thread but this helped a great deal.

Don't forget we want pics, turbo. D Stewart39035.6724652778

Great info here, thanks fellas!

Turbo, if you see splotchiness, you haven't gone far enough. There is still epoxy on some of the areas.
I'm in a different camp than pretty much everyone else here. I sand it back level and finish on top of the epoxy. I had a guitar that I sanded through and thought the wetting effect of the finish would just soak in and it would all be good. NO LUCK. It looked very bad.
So don't stop until you see all the blotches go away.

Paul,
I, too only sand back the epoxy to smooth. Not to the wood. I feel like it ensures me a more consistent finish. Frustrating when I "sand through", but I like the epoxy. It seems it would provide a tougher under armor for those who fear that KTM-9 is too "soft", too.
I like putting the finish directly to the epoxy. Just the back and sides, though.
The thinned alchohol seems to have a soaking effect on the wood and seems to absorb into the wood just barely enough (more than full strength epoxy) to make it look different and therefore causes the splotchy look. That's my theory...err..hypothesis, anyway.
Maybe I'll try sanding back to wood on this next one.


-j.j.Brown39035.7766666667

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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