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Is there any way to speed up the cure time of nitro lacquer? I hate the slow cure time worse than anything else about it. Maybe some type of heat lamps or lighting would do the trick? I would appreciate any info I can get.

Colby, I may be off here, but I think John Mayes used to use UV lights...

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http://www.presnallguitars.com

Patience..... I tried UV lights on a KTM finished guitar a couple years ago, setting it up farther away than the Manufacturers recommended and leaving it on less time and ended up bubbling the finish and had the center seam come loose so be carefull and keep a close eye if you try it. I now jst wait till it cures naturally.

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Tickle your guitar daily, and it'll tickle you back.

you can use UV lights (got the tip from Lance M, who got it from John Z) but
beware, DO NOT leave it in he box for more than a couple days or it will
crack the lacquer... also DO NOT enclose the box totally.. the lights do
generate heat and WILL potato chip your fretboard!

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John Mayes
http://www.mayesluthier.com

Regular nitro lacquer is not intended for UV curing, and I would worry about what it might do to the longevity, even if it speeds hardening. Apparently it risks bubbling or cracking the lacquer. What I do, which is as far as i would go toward speeding the cure, is hang them in a small room with one of those electric oil filled heaters (to give a gentle well distributed heat to the air; I would avoid any radiant heating), and bring the room temperature up to about 90?.

Really, my thoughts when reading your post are: What is the rush? Is it so important that you are willing to risk ruining the finish? Guitar making isn't exactly the thing for impatient people. Start another guitar and give the finish the time it needs.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I would add getting a little air movement going in the room as well, a small fan perhaps...
But like Howard says, what's the rush. It just takes time for this stuff to cure properly. If you rub it out too soon, it will "crinkle" on you as it cures more after you have rubbed it out, and the laquer on the spruce will sink into the early wood a little and give that furrowed look.

3 at least - 4 weeks if I can spare the time. 4 is much better. I had a couple sit around for 5 months while I did other stuff (no rush on them at all), and they were amazing to work on.TonyKarol38888.6665972222

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

I agree with Tony, if you can wait 5 or 6 months, you'll likely get a finsh that won't shrink back at all after buffing.

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Tickle your guitar daily, and it'll tickle you back.

Thanks for the input guys!

How much would you guys say putting it in a 90 degree room would help? Do you think it could cut the time in half? Have a months worth of natural room temp curing in two weeks maybe?

The biggest reason I would like to speed up curing time is because if I'm trying something new like a different bracing idea, I would like to be able to play the guitar before I get to deep into the next one. The effect may or may not be something I want to repeat.

    I was using UV lights to cure my lacquer for years and found that it was really best to just give it the time to cure in the open air and naturally. I was with John on several occasions and his UV curing "closet" as he called was the same size as mine and wasn't completely closed and well ventilated to promote temperature control of the air around the guitars.

   I only used my booth when there was a rush on a guitar and the finish needed to be pushed a little. Any other times, I gave them a full thirty days to cure after the top coats were sprayed. Even with that period of cure time, the finishes still shrink with time. With nitro lacquer, there will be signs of shrinkage no matter what cure time you give them before sanding and buffing. Longer cure times will proesent less shrink back, but they will shrink somewhat as the years go by.

The UV lights do generate more heat than you would expect so keep tht as a serious consideration.

   As far as a 90 degree room cutting the time in half....I highly doubt that it would cut nearly that much time off of the cure cycle.

Regards,
Kevin Gallagher/Omega GuitarsKevin Gallagher38888.7757060185

It helps a little. I still wait 3-4 weeks before rubbing out. More is better. Forget about the speed cure, or else go to a polyester finish that cures with chemical additives (which I cannot help with--Mario has posted here about it). My recommendation is that you exhale and get in synch with the natural pace of the work. A difference of a week or two per guitar is not going to keep you from realizing your R&D interests.Howard Klepper38888.9827893519

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Colby have you already applied the finish. The reason I ask is when I do a test guitar I would not finish it in a lacqure. Rather a French polish or KTM9. French polish you can string it up with in days of application and KTM9 with in two weeks or less if cured in 90 deg+.

Colby,
Why not just use a catalyzed product if you are in a hurry?

Most of the really good builders that I know would love to shave a few weeks off of their lacquer cure time. The fact that they don't implies to me that they haven't found a safe way to do it. Nobody likes otherwise billable production sitting around for a month or more. The cure time is the main reason many of them have switches to catalyzed poly (UV or chemical).

Poly is really nasty stuff and you should wear a space suit while working in a properly designed spray booth. Nitro, on the other hand, is really nasty stuff and you should wear a space suit while working in a properly designed spray booth. I think you die slower with nitro, though.

I have heard, from Mario I think, that UV has too high of a capital investment but chemical cure poly is significantly easier to get started with.

I don't usually spray my finishes I F.P.them. However, on a recent re-finish job I sprayed Nitro on a Rickenbacker Bass. Clear/Natural(Pre-sanding/leveling and pre-buff, it was close to .015 in thickness...the old "tape in the pickup cavity" trick). I waited a Full 4 weeks, and it buffed out real well. Looks like glass...I can see why everyone wants it to look like Nitro. Anyway, even after 4 weeks, it still seemed just a little tacky to me. Is that natural or is something else going on. I live in Florida so I air condition my shop...Average temp is about 75* and hummidity is always 45-50% I try to keep it closer to 50% because people take their instruments home and the average house is about 70% hummidity even with constant a.c. and that changes the set-up. ANY THOUGHTS?

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Robbie

I would like to learn more about the catalyzed products. The reason I'm not using them is because I know nothing about them. Do you talk about them in your finishing DVD??

Colby,

I discuss catalyzed urethane in my Finishing DVD and show how to apply it to a guitar. This is the post mix variety meaning you mix it at a one to one ratio.
I also discuss and demonstrate a pre catalyzed lacquer meaning that it already comes in the can pre mixed.