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I applied a couple coats of zpoxy on a neck, sanding between coats, and then put final coat thinned with alcohol 50/50, when dry I went over with fine steel wool. neck looks beautiful as is. Here are my questions:

Will true oil over the zpoxy sink into wood? Seems like I have a zpoxy barrier with that final coat that was thinned to eliminate blotching. I suppose I could sand back to bare wood leaving pores filled but thought I read directions to fininsh off with final coat thinned with alcohol.

My other question: the neck looked great and was slick as could be with nice flattened finish. What if I put a couple more coats of zpoxy thined and sand between coats to get some build? Do you think this would wear well over time? Sure looks and feels sweet.

Rich: For most of my guitars I have generally used nitro and a couple unfilled with Polymerized Tung oil.Last winter I did two that I tried Zpoxy as a fill and polymerized Tung oil.Those two did not stand up very well.Almost like there was a reaction between the Zpoxy and the polymerized Tung oil.I'm not sure if the true oil and what I used are the same or not.If you like the Zpoxy alone I think it should be ok.Just trying to tell you to be careful.Hopefully others will give some more info.Good luck.
Tom.

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A person who has never made a mistake has never made anything!!!

I've had the same issues with Tru Oil over Z-Poxy. Good at first and later getting fuzzy. Sand back and it has gotten fuzzy again in a short time. One where I sanded the Z-Poxy back to bare wood with no thinned coat has held up for about 6 months. I don't plan to use Tru Oil over Z-Poxy in the future.
TJK

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Rich,
Based on others response, I'd use something else. You could try a wipe on gel varnish and I bet it would hold up real nice. I've been using brushed shellac on top of zpoxy on the last few instruments I finished, and they turned out beautiful. But I hear shellac doesn't hold up as much. But I love the feel of a shellac neck.

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Tracy
http://www.luthiersuppliers.com

Thanks guys. I might go the french polish route on this one over the zpoxy based on your responses. I like the feel of FP on neck and have been able to get good results in the past. Little too soft on the body for serious wear and tear.

I'll offer a few words: Tru oil is a nice finish,but I swear,it will print like crazy if left in a case. I finished a violin once with it. The violin hung for some months strung up. I noticed one day that the Tru Oil had spurted completely out from under the feet of the bridge clear down to the BARE WOOD!

About the epoxy: I use thinned out epoxy to fill wood,but always sand it down to the bare wood,just leaving it in the pores. I use 5 minute epoxy,and sand it after a few hours,when the epoxy has dried LEATHER HARD. It just rolls off nicely with 220 grit paper. Wait too long,and it's like sanding concrete. I would NEVER use steel wool. It might take some of the epoxy out of the pores. I use nitro,and have had no problems with it adhering. But,remember,I do not leave the surface coated with epoxy. Just the pores.

I recall a few post from the past about the compatibility of epoxy pore fillers and top coats. Maybe a search of the archive will give you some answers. There are quite a few guys on here that swear by epoxy that haven't posted much lately on here.

The problem here is the amines blush rising to the top of the Epoxy. It's a kind of waxy thing that can't be removed by solvents. Sanding the Epoxy seems to merely spread it around rather than remove it. Believe it or not , water and a mild soap are best for removing this blush ( with a Brillo pad ). If any of the amines remain it will cause a reaction with some finishes such as Tru-oil ,giving a fuzzy feel. Some folk have also reported the same reaction with a shellac finish .

I'm told that system 3 Epoxy doesn't have this amines problem , but having not tryed it , I can't confirm this.

Z-poxy certainly has !! Yes,, I too was bitten ! ( 1000 curses ! )

Regards

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CRAIG LAWRENCE of AUSTRALIA
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Every neck I`ve done with z-poxy pore fill,no matter what finish gets that fuzzy feel.Tru-oil has a filler they sell,which I`ve used,but doesn`t seem any better than just a lot of coats of Tru-oil which comes out great.Has anyone tried filling with CA and then going over it with tru-oil?
James

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James W Bolan
Nashville Tennessee

Can't help you with your question about filling with C.A. James as I HATE the idea . I've had great success filling with fine wood dust/shellac and more recentley egg white and fine wood dust .

A whole lot better than using those dangerous chemicals .

Apart from Z-poxy giving you "the fuzz" it's PARTICULARLY HAZARDOUS ON YOUR HEALTH

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CRAIG LAWRENCE of AUSTRALIA
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I have had the same problem with zpoxy. I'm going with egg white/wood dust
on my next guitar. I'm done using zpoxy.

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Anderson Guitars
Clearwater,Fl. 33755

Truoil has a great feel on the neck but as has been indicated already, 'amine blush' can make most epoxies (and most that we use are in fact amine cured) unsuitable under any type of finish which requires polymerisation of driers to take place in order to harden.

The reason for this is because when these epoxies are mixed, applied and cure in the presents of carbon dioxide, amines will excrete from the hardening mix and rise to the surface. This produces an oily residue which is known to retard, prevent, or even reverse the polymerisation process of certain finishes. As Craig suggests you can wait until the epoxy has cured and wash most of the residue from the work piece before sanding back. But it is worth keeping in mind that epoxy never really fully cures and therefore the reemergence of amines 'under' the finish at a later date is not only possible, but if the carbon dioxide count had been high enough during application etc, it is quite likely.

If you wish to use Truoil without this issue being a problem, the solution is simple. Fill the grain with paste filler, micro beads, egg whites, shellac and saw dust or anything other than epoxy. You could even use the product manufactured by Cassey specifically for use with Truoil.

On another note, i would strongly advice against anyone sanding epoxy within a few hours of application while it is still "leather hard". The chemical exchange at this time is still quite active and you would be inviting the development of contact dermatitis and an on going sensitivity issue with these products. If you use the correct epoxy product to fill grain, which is essentially a 'sanding' resin, it will sand beautifully once fully cured and you are much less likely to develop any health problems.

Cheers

Kim

Kim I`ve used the product Cassey sells that`s suppossed to fill the grain before applying tru-oil.It doesn`t really do that good of a job.Maybe I needed more coats ,not sure.That`s why I was wondering about CA under.
James

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James W Bolan
Nashville Tennessee

Kim,everyone's skin is different,it is true. But,I have been using my epoxy technique since the 80's,and have never had any issue with my skin,or with the finish blushing. I am not using Z-poxy. Maybe you guys should try another brand? An issue I HAVE had with my skin was in sanding 100 year old Honduras mahogany that had been used in an old ship's cabins. My skin got a rash because the old mahogany had fungus in it,though it could not be seen. My woodworking doctor friend was aware of the problem. I hope my 100 year old Cuban mahogany doesn't do that. It wasn't used in a damp ocean atmosphere. I used some of it,and no rash from it yet. You also need to be very careful of spalted wood. It is full of fungus,and very bad to inhale.

Better take my advice about the Tru Oil,though. What I said happened did happen. I'd be afraid to put an instrument into a case with Tru Oil as a finish. Might print. I can assure all of you that I waited several weeks,maybe months before stringing up the violin with Tru Oil on it.

Filippo,I assure you that the violin I tried Tru Oil on remained hanging in the shop for a very long time before I ever fitted the bridge and strings to it. There was no epoxy or other filler used beneath it.

I worked in a museum workshop open to the public for many years,and things happened very slowly due to meeting the public. I am not putting Tru Oil on any more instruments. Others may do as they wish,but I hope they don't find out the hard way.

I don't use tru-oil or z-poxy, but wouldn't a coat or 2 of shellac take care of the animine blush problems?

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I might use tru-oil over a cellulose pore filler. Do you think it is compatible?
Thank you

Cellulose should be fine.

As for using shellac to seal in amines it probably won't work. I believe shellac under goes it's own process of polymerisation as it hardens. This is why dry shellac flakes have a limited shelf life, exposure to oxygen starts the polimerisation process and once effected, they will no longer dissolve in alcohol. If this is the case then the amines would probably retard that process and explain why some folks have experienced amine blush with FP. By the way, amine blush is not something you will at first see, it's not at all like moisture blush you see under nitro. Rather amine blush is something you at first 'feel' as a softish fuzz as the finish covering the amine excretion begins to soften. As it does so, the finish will then start to pickup sweat and dirt and then you will most certainly see the affected area.

If using truoil to finish a guitar, I suggest you do not use the application method recommended by the manufacturer as that is for gun-stocks. If you do use the Cassey regime, the finish will be thick and never harden out enough to polish up to a good gloss and protect the instrument. You are far better to follow the instructions at the link on the LMI web site which relates to the truoil product. Another point, as the oil driers work to harden these types of finishes over a few months, they will continue to 'gas off' the more volatile elements. If you seal the instrument in a case covering the surface of the finish with micro thin synthetic case lining fibers, my guess is that you could fully expect those very same substances now escaping from the finish which had once dissolved it into liquid will easily soften the micro fibers of the case lining enough to cause much grief.

My opinion is that truoil remains a very good finish, but if using it, stay away from epoxy fillers and apply many 'very thin' coats even buffing by hand between to burnish as you build the finish. One done, leave it to air for weeks (longer is better) then buff and polish.

Cheers

Kim

Just to add to that Kim. My daily player has a tru-oil neck and hasn't shown a sign of wear over the last 5 years. Fairly impressive when you consider all that hand grasping ,occasional sweat and grime etc. etc..

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CRAIG LAWRENCE of AUSTRALIA
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Great info Kim. The "fuzziness" progressing to breakdown is exactly the problem I had with Z-Poxy. Nice to know what caused it. The thing must go on a long time as my first Tru-Oil/Z-Poxy neck which is two years old has been sanded smooth several times and the fuzziness keeps coming back.
TJK

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Thanks a lot Kim for all the information. I started to have some doubts about tru oil....

For 5 years all my necks were fill with Zpoxy and top coated with tru-oil. not one of the 50 plus has ever given me a problem. i never left a noticable film of Zpoxy on the neck or on ant body for that matter. After filling I always sanded back to just at wood level leaving Zpoxy only in the prores. I the applied a very thin 60% alcohol/40% Zpoxy mix wiped coat just to even out the color but leaving no noticable film thickness. after all is curred out I would sand with 000 steel wool or 400p to remove all the shine. then I would start applying tru-oil 2 padded coats a day for 4-5 days. allw a week to cure and rub out through 12000 micromesh and buff if desired on through extra fine menzerna on the power buffer.

I suspect that those that have had issue have left a noticable film thickness of Zpoxy on the neck prior to finishing the neck. my thoughts would be that this leaves a relitively soft substraight under the tru-oil that has lead to the Fuzzy felling you experianced.

i have for 2 years now used CA to fill almost everything. Again leaving it only in the poares when finishing with any conventional finishes from nitro to varnishes. A sealer is never a bad idea if using nitro. I seal with 2# shellac. I have several neck out now that are 100% CA finish and so far I am well pleased with the results. It producess a very hard, very fast highly polished top coat that wears great.

You mean there`s nothing on the neck but CA? how many coats.
James

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James W Bolan
Nashville Tennessee

Amine blush is not a brand thing, it is a epoxy thing. Some epoxy types blush worse than others. You can recoat without cleaning with water and sanding if the epoxy hasn't set up. If it is still sticky or tacky you can apply a second coat. If it sets up you have to remove the blush. You do this by washing with water and detergent and then sanding to smooth and tooth the surface.
The info I am giving applies to epoxies in general.
I don't know about Z-poxy, I have never used it. It may be a low amine producing epoxy and may not blush much but it could under the right conditions.
Link

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Cut to size.....Beat to fit.....Paint to match.

Tru Oil over cellulose pore fillers? Yes. Over most anything oil based (like oil stains)? Given some drying time before applying the Tru Oil, I'd say yes. Over shellac? A qualified yes, because it depends what is under the shellac. Over other stuff? Maybe. Maybe not. Listen to other people for that answer. It's versatile stuff, but it's not a silver bullet. I love the stuff, but I don't ever pore fill with epoxy. I'm glad I read this thread, because I was considering doing that real soon.