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I will be nearing the finishing stage soon on my latest (#4), a cutaway OM. I have used Tru-Oil before and have been pleased with the results, but I was considering Minwax Wide-On Poly. I have read on the OLF that some folks have gotten good results and that it is easy to use. Does anybody have any thoughts that they want to share? How many total coats? ...leveling after 3 coats..., etc.?

I use minwax standard fast drying polyurethane, but have been using wipe-on poly a lot before. First question is what wood species did you use? Some rosewood oils will prevent the polyurethane to cure properly (it will take between one and two months to fully cure!). If that's the case, than you must carefully seal with shellac, and make sure you don't sand through between coats (or else re-seal the sanded through area with shellac ).

The reason I stopped using wipe-on is that I found it took too many coats to get enough build-up (like 20 to 30!). And it left too much dust particals in the finish.

Here is what I do now:
- build up with several coats brushed on (with a foam brush), ligthly sanding with 400 grit wet between coats. I do about 8 coats, but it will depend on good the surfaces of your guitar were. Just keep on applying coats until all voids are filled.
- Level sand with 400 grit wet
- apply a coat normal way
- level sand with 1000 grit wet
- apply a coat with a paper towel around your foam brush (that leaves an almost mirror flat coat)
- level sand with 1500
- apply a final coat with a paper towel around your foam brush
- lightly sand with 2000
- buff with menzerna medium and then fine.

Hope this helps!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

There's an old thread (you may have seen it) where Mario Proulx and Rick Turner slam minwax. Rick mentioned liking the Waterlox wipe on varnish a lot more, I'm pretty sure. Make of it what you will...

Yes, I've read that. They don't talk about Minwax specifically but about polyurethane overall. But as much as I respect their knowledge, I've got 25 guitars finished with polyurethane and it's giving me great result.

On top of haveing a hard time curing on rosewoods, the main bad thing we hear about polyurethane is that it doesn't stick well to wood. That has not been my experience. I noticed that it doesn't stick at all to any sealer made for lacquer or to lacquer itself, but if you apply it to bear wood, or to properly cured shellac, than your good.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Hope I am not changing the topic too much, but I used to use a varnish made by Pratt and Lambert, number 61 in fact, and it would dry wonderfully well over rosewood. When you sanded it between coats, the varnish sanded off would make little rolled up pills that would keep the sandpaper clean. If you waited too long between coats that feature would go away, but at any rate, it was great to work with. Rapid build, self leveling, and since it oxidizes rather than evaporates the finish is linked and tough. I never had a problem with adhesion.

That sounds like a pretty cool, and quick finish for a neck John .. wonder if I can get that stuff in Canada ???

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

Go to there website: http://www.prattandlambert.com/ , they have a 'where to buy' function (upper right corner) where you enter your postal code and they list retailers near you.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I went to their site Alain and could not find that product listed. They may have discontinued it. I wrote them a letter and asked if they still made it or if they had a stuitable replacement, or maybe had a few old cans of 61 stashed in the warehouse that they would be willing to part with.

When I first read through that famous polyester thread (where Rick and Mario talked bad about polyurethane), I wrote to Mario to ask him what he suggested as a replacement, and he suggested Pratt&Lambert #38. I couldn't get my hands on it at that time and simply decided to check that out some other time, but never did.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I've used this stuff on several guitar and bass necks over the last two years. Several electric instruments and two acoustic guitars so far, with very good results. My first three acoustics I used Nitro lacquer, and on the fourth I used KTM-9 for everything. I "discovered" the Minwax product and used it on a bass neck about 2 years ago, and found it very easy to work with, and it makes a great feeling neck, so I started using it on acoustic number 5, and loved the ease of application as well as the feel of the neck. I used the gloss version, but it's not really gloss anyway - more of a shiny satin.

Somebody on this thread said it takes a lot of coats to build up a decent film, and that is certainly true.

--Steve

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---Steve

Alain - I will be using z-poxy for a seal coat so the issue of applying directly to the bare wood should not be a problem. The back and sides on this build is Koa... Your finish schedule looks like a winner. I didn't realize that it would require so many coats. Thats the same thing about Tru-Oil. I thought I might not need as many coats. Is the poly that much harder or better than Tru-Oil?

I had read that Robbie O'brien said good things about Minwax Wipe-On...

The thread: http://luthiersforum.com/forum/viewtopic.php?f=10102&t=14771&p=210188&hilit=wear#p210188

First, maybe I did not make myself clear before, but I did not experience any problem when applying polyurethane directly to wood (unless with rosewoods, of course...). And I also use epoxy as a pore filler, without any issues related to that either.

I don't know how polyurethane comnpares to Tru-oil, I never tried it. But poly is not that hard, more flexible than lacquer for sure.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)