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So someone needs a dent fixed in a week.Of course it`s nitro.It looks like it will drop fill okay,with 2 or 3 applications,but how can I level and buff it out in a week? Is there any possible way.Maybe run a pretty strong fan on it?
James

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James W Bolan
Nashville Tennessee

Use a hair dyer placed about 20 inches away from the fill. I monitor the temp with a thermometer and it gets to about 115 - 120F, you should monitor yours if you do this I would not get it warmer than about 120 much above 130 and you'll more than likely bubble your lacquer. You can sand in about 8 hrs later or so.

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Jim Watts
http://jameswattsguitars.com

Jim are you saying ,that when the temp reaches 120 to turn the hair dryer off,or is there a certain amount of time that this temp should be maintained?This is good info. Thanks
James

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James W Bolan
Nashville Tennessee

No, let it blow on the area constantly blowing the 115 degree air or so over the fill. I think you'll be pleasantly surprised how well this works for a drop fill.

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Jim Watts
http://jameswattsguitars.com

Jim when you say constantly.you mean like 8 hours or so.
James

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James W Bolan
Nashville Tennessee

yes

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Jim Watts
http://jameswattsguitars.com

Okay,i`ve got it cooking.this whole scenario brings up another huge question.If this can be done on a small area,why not on the hole guitar.Maybe fans and some halogen lights could accelerate the whole nitro cure process.Any thoughts on that? And thanks again for a great tip.
James

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James W Bolan
Nashville Tennessee

There are a couple of problems doing that on an entire guitar. One is that if you heat the guitar while you're spraying, you can get bubbles when the lacquer skins over before most of the solvent has off-gassed.

You would also need to do something drastic to control humidity. Bringing the heat up to 100 degrees or more would bring the humidity down fast.

Other than that, it does speed up the cure. Furniture factories typically use curing ovens for their finishes.

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http://www.chassonguitars.com

Kent I`m sure there would be some problems.This is probablyly a whole different post.I`t is an interesting thought .I`m sure with all the intelligent people on this forum someone could possibly figure something out.The cure time on nitro to me is it`s biggest drawback.
James

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James W Bolan
Nashville Tennessee

Jim, would there be an issue with the dent showing up again after the lacquer cures and shrinks back in the dent area?
Thanks
Nelson

Nelson,
I'm sure there is, just like in any drop fill. Obviously blowing hot air over a solvent doesn't really do anything except make it go away faster.
I was in a pickle and had to do this once and was able to see the guitar a year or so later and didn't notice the fill.
I probably had the hair dryer on it in multiple sessions for close to 40 hrs over the span of a week, it definately speeds it up a lot, but it's still nitro.

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Jim Watts
http://jameswattsguitars.com

Jim, interesting stuff!
There's times it would be nice to speed up the cure process on nitro drop fills. Will have to give it a try. (on scrap first of course)
Nelson P.S. There's probably hair dryers out there that wouldn't last 40 hours.

It worked real well.I had the dryer on it for about 9 hours yesterday.This morning I leveled and buffed.It`s barely noticeable.
James

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James W Bolan
Nashville Tennessee

James, if you've got the time, put the hair dryer back on it and check for additional shrink back. repeat if necessary.

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Jim Watts
http://jameswattsguitars.com

When I leveled I masked the area off and this left it a little high.I figure it will probably shrink a small amount.I`m real leary of sanding the surrounding area.I`ve done this before and had to re sand and buff the entire top instead of just the damaged area.If you think I still need to put the dryer on it ,I`ve got time.
James

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James W Bolan
Nashville Tennessee

James and Jim and everyone else interested:
With the risk of taking a simply elegant solution and making it complicated; I have to wonder if this would be a good application for a concentrated beam of infra-red? (Is there such a thing? Maybe think IR maglite ) Just thinking this might work in areas where one doesn't want to heat the surrounding area whether it be for reason of not softening glue, binding etc.
Again, not wanting to derail an excellent discussion but hopefully expand on it.
Thanks
Nelson

Nelson, I would worry about getting the lacquer too hot and bubbling it . I don't know what the magic number is for that, although I don't believe it's terribly high. I suppose a rheostat should give you good controll of the temperature though. Also I think moving fresh air across it also helps with evaporation of the solvent, it's kind of a two fold thing.
It certainly could be worthwhile to try on some scrap.

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Jim Watts
http://jameswattsguitars.com

No one "needs" an accelerated repair. They want one. I learned to tell them that it takes as long as it takes to do it right. If that doesn't work for them, send them to someone else.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

http://www.opentip.com/Apparel-Shoes-Jewelry/Ultraviolet-Led-Light-Source-Led-p-1503006.html
Here you go, Howard.
Awe, cmon you know you want one.

If the dent is deep, you can fill most of it with CA, then top it with a few thin coats of nitro. I use a small fan at a low setting to speed the curing. In my experience, heat is too risky. Too much of a chance of bubbling the lacquer.

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John

I like to laugh, Nelson, but this joke is eluding me.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.