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I just put some ZPoxy on a neck and it has this strange milky/blue cast to it. Anyone seen this? I don't think it'll show up in a pic but I will try later.

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If anything it's usually a warm amber. Are you sure it's the Finishing Resin?

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JJ
Napa, CA
http://www.DonohueGuitars.com

Yeah I know JJ. But is the only thing on the neck at this time. I dyed the main neck and the pic is of the head plate which is blood wood. Same effect on all surfaces. I noticed the same thing on the main body blood wood as well but attributed that to the waterborne finish. Now I am SURE it is the ZPoxy as it is the only thing on the head plate and neck.

It look like e reflection but believe me the color in the pic is very close to the color apparent on the finish.

And of course I spent days dying the neck and getting the color right so to remove the ZPoxy creates an amazing amount of work and am then faced with what finish to use.

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Zpoxy has several formulations. My question referred to whether it's their "Finishing Resin"...PT-40.

I've used ZP on a bloodwood headplate and it never looked like what you are showing. Did you lay down a thin coating with a card spreader? It looks quite thick.

How does it look if you scrape it off with a cabinet scraper?

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JJ
Napa, CA
http://www.DonohueGuitars.com

Yeah finishing resin. And quite thick as well. Not needed to be thick on the head plate but I just wanted to have plenty to sand off. The neck is a different story. It's dyed and I want it thick so I don't sand through.

But I'm not sure that's the point. Did you know it turns blue if it is put on a bit thicker? And it's not really that thick as only so much will stay on as it cures.

Does not sound like you have ever seen this happen. I'll let it cure and see if it changes. Can't scrape yet as it's still gooey. And can't scrape the neck as it will surely go through and destroy the dye job.

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I have used the stuff and did not get any blue color. I wonder what temperature the room was when you applied it? Also, was there any residual moisture left in the neck from the dye? Moisture can do some strange things to finishes as I am sure you know!

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

[QUOTE=LarryH]
...Did you know it turns blue if it is put on a bit thicker?...
[/QUOTE]

No...and I've never seen it "blue" even in at 1/4" thick in a mixing cup.

My comment on the thickness was based on how thick it looked in the pic. Keep it thin...real thin!

You're showing something that I've never seen nor have I ever heard of others reporting such a radical color change. If you can't attribute it to a contaminant or moisture, I'd recommenc calling ZP customer service.

This is so weird...the PT-40 Resin is clear and the PT-40 Hardener is reddish brown. How do you get blue out of that combo? Steve may have hit on something related to moisture...puzzling.

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JJ
Napa, CA
http://www.DonohueGuitars.com

I've never seen it blue either, and like JJ said, even leftovers in the mixing cup cure to a nice amber color.

I wonder if it's reacting to your stain?

Yeah you guys all valid concerns.

It was chilly (San Diego) this morning 45 maybe? Mixed the ZP and brought it inside immediately. Cured inside (68) for 6 hours.

The challenge is that it is occurring on both the stained and unstained areas so moisture doesn't seem likely. AND the stain is alcohol based which we all know mixes VERY well with epoxy. And the stained areas dry VERY quickly because of the alcohol.

The color ALSO appears on the main body (back) of the blood wood - but NOT THE SIDES. Can't get it to show in pics but it looks psychedelic purple with the blood wood - but only when in direct sunlight. I figured it was the waterborne doing its bluing thing until I saw it with just the ZPoxy.

I know it is weird but it is very real - and very blue.

Seems to have mellowed a bit with curing but still very noticable.

Larry

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And you are using this stuff in order to do what? Fill grain? As a sanding sealer? Why is this particular brand mentioned so often? There are lots of good epoxies.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

[QUOTE=Howard Klepper] Why is this particular brand mentioned so often?[/QUOTE]

Lots of people have reported good experiences with it. I just tried it for the first time, and compared to the brands I have used it was a joy to use, especially the sanding part. It turned to dust where other epoxies would have gummed up the paper. I treated it like I usually do with fillers however, which is to fill only the pores. That means sanding back to bare wood, but stopping before too many new pores are revealed. I think most people leave a thin layer of epoxy under the finish.

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Rian Gitar og Mandolin

Howard...I can only speak for myself. I've used it on 6 guitars as a pore filler under Nitro, KTM-9 and FP. It's easy to mix, goes on thin when applied with a credit card, sands back easily and imparts a slight amber tone. All of the above finishes have bonded tenaciously after 3 years of service.

I would include ZP in the "lots of good epoxy" category in spite of the "bluing" anomaly as described in this thread.

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JJ
Napa, CA
http://www.DonohueGuitars.com

[QUOTE=Howard Klepper] And you are using this stuff in order to do what? Fill grain? As a sanding sealer? Why is this particular brand mentioned so often? There are lots of good epoxies.[/QUOTE]

Howard,

I am intending to use the Z-Poxy as a pore filler on the neck and head plate before I finish with CrystaLac waterborne finish. I dyed the neck and wanted to protect it with the epoxy so I would not sand through the dye (which has taken days to get right). I put too much on the head plate but I sanded through in spots any way.

The blue has diminished but is still there.

I chose the Z-Poxy finishing resin after reading a lot of recommendations here. I tried System 3 - 30 minute epoxy which will hold a house but it takes a very long time, as was mentioned, to get hard enough to sand efficiently, and if you miss the mixture it can be a disaster.

The Z-Poxy finishing resin sands like a dream, as was stated, and makes it at least possible to use as a pore filler. For other uses, I agree, there a re many epoxies that will do the job. As a pore filler I haven't another as of yet.

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OK, I get what you are doing. I use epoxy for pore filler, and have had good results with 5 minute Devcon from the hardware store, so I haven't bothered trying anything else. It does not powder when sanded, which I can see is a big plus if you apply the epoxy thick. I squeegee mine in with a dulled razor blade, and try to leave as little outside of the pores as possible, so the sanding isn't too bad.

But I don't use epoxy to fill necks, because of the difficulty squeegeeing off the excess on the curved surface. I go with conventional filler for necks. It seems to me that epoxy is going to commit you to sanding, and you can't use it when you don't want to sand into dyed wood and mess up the color. For a dyed surface, I would spray a couple of sealer coats of shellac (I understand that this can be an issue for waterborne finish, but I hear that dewaxed is OK) and then use a conventional oil-based filler that does not need to be sanded after wiping clean.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

[QUOTE=Howard Klepper] OK, I get what you are doing. I use epoxy for pore filler, and have had good results with 5 minute Devcon from the hardware store, so I haven't bothered trying anything else. It does not powder when sanded, which I can see is a big plus if you apply the epoxy thick. I squeegee mine in with a dulled razor blade, and try to leave as little outside of the pores as possible, so the sanding isn't too bad.

But I don't use epoxy to fill necks, because of the difficulty squeegeeing off the excess on the curved surface. I go with conventional filler for necks. It seems to me that epoxy is going to commit you to sanding, and you can't use it when you don't want to sand into dyed wood and mess up the color. For a dyed surface, I would spray a couple of sealer coats of shellac (I understand that this can be an issue for waterborne finish, but I hear that dewaxed is OK) and then use a conventional oil-based filler that does not need to be sanded after wiping clean.[/QUOTE]

Very helpful Howard. I've never used an oil based filler and applying epoxy to necks is a bear as you imagined. Lots of goobers to sand and a lot of work to get right.

Thanks for the advice.

larry

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Squeegeeing the excess Zpoxy off on a neck - use your finger after the epoxy sets for 20 minutes (nitrile glove on of course).

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"