Thread: Curing lacquer

Originally Posted by old_picker

I thought of a cabinet with a couple 100 watters with a few 100mm computer fans ???

I do a simpler version of this Ray, it speeds things up a lot in the cool weather. Just an old wardrobe with a couple of 60w globes in the bottom. The fans might be an improvement though, get the solvents out a bit faster maybe.
jack

How long does it take in the wardrobe??

I use Acid catalyst lacquer, and Nitro Cellulose, so these times may not be the same as for the water based ( which I've not got around to using but have read a lot about...I saw some good demonstrations at the 2004 guild of american luthiers convention...so be really interested in your experience)
For me I spray a grain filler coat, heavy on, to start with. That needs about a week to dry normally, in the wardrobe it takes maybe three or four days, till I cant smell the solvents any more. Then I cut it back to wood and spray it again with a similar dry time.
So for me its a usefull way to reduce a roughly two week process down to about eight days, if all goes well.
Its especially usefull cold wet times ( not uncommon in my this part of the world!)
I have an old wardrobe I found in a shed, its big enough to hang two guitars easily, three cramped. I find the two 60w globes keep the temperature up around 25 to 30 degrees.
Generally I don't need to use it to speed up the drying as it takes my a couple of weeks to get around to sanding them anyway, but it still improves the overall hardness and eventual shinyness if I at least put the instruments in the wardrobe for an hour or so after they have been sprayed.
I know the water based lacquer is very different to deal with, but what I've read and heard about it makes me think that warming it up should be good. DO you find the heat lamps make for a harder finish in the end, apart from any time advantage?
Jack

Originally Posted by Jackspira

I use Acid catalyst lacquer, and Nitro Cellulose, so these times may not be the same as for the water based

I've got a friend who uses Acid Catalyst and recommends it to me. Do you use the one from Mirotone? How do you like it? Can you use dyes in it to make shader coats?

Originally Posted by Jackspira

I know the water based lacquer is very different to deal with, but what I've read and heard about it makes me think that warming it up should be good. DO you find the heat lamps make for a harder finish in the end, apart from any time advantage?
Jack

Water based is a lot cleaner to use. ie clean up with water and you are not breathing thinners or working with a combustible spray. Apart from that the finish is easily as hard as nitro, Buffs out to a mirror fiinsh. It is pretty much the same as using nitro as far as the tecnique. Use a sanding sealer coat[s], shader coats and finish coats. Cut with wetndry, buff out with cutting cream and polish. It does burn through if you go too hard with the buffer. If not properly cured it will shrink down into the low spots a bit as the weeks go by.

The arc lamps are good but if you get a good thick coat on and stick right under the lights the finish tends to pit as the volatiles bubble off and the holes formed dont heal up. It definetely speeds up drying time. You can get 3 good coats a day on.

As far a making the finish harder that would need to be answered by someone who knows a lot more about the chemical reactions in the finish. The legth of drying time, humidity and temperature are the factors that allow the lacquer to set. Thicker coats take longer to cure.

I am not sure how it sets:
from inside to out
outside to in
all over at once

perhaps someone else may care to comment

Mmm, the water based lacquer sounds great, you're definitly getting me more motivated to have a go!
Phil- the Acid Catalyst Lacquer I use is made by Air Lac, a Greek company that has a factory down here in Melbourne. I have used Mirotone acid cat in the past too, and it was fine. Its a pretty old fasioned lacquer I think, but seem to work well for guitars, very similar to nitro from an acoustic point of view. I like it coz it goes off a bit faster and harder than nitro and is much much easier to sand! It doesn't sink back anywhere like nitro either.
Its quite forgiving for a two pack. I've never had it fail to go off because of getting the mix a bit wrong, or from oily wood surfaces like cocobolo, which some epoxies and polyesthers dont like.
Like nitro it tends to go yellow with age and can craze in a similar way. The yellowing doesn't bother me, I like it.
I'm pretty certain you can use the same tinters as for nitro.
It also bonds well with nitro, so for instance, its possible to use the acid cat as a grain filler and coat with nitro over the top. Its also possible to touch up a small patch with nitro, over an acid cat surface, saves mixing up the two pack when you only need a very small amount to do a repair.
Its still a horrible solvent based lacquer though! I have seen some beautifully finished guitars with the water based.....

Thanks for the info.

these were both done in wb lacquer
i have 3 more in process will post as I buff them out
hard to see in these pix but a good deep mirror shine

Nice! Thanks Ray

Originally Posted by old_picker

Wonder if any of you guys have a way of fast curing guitar lacquer.

Hello from London, UK.

The fastest way that I know to finish wood is with cyanoacrylate, (aka super glue).

I never tried it with anything as large as an entire guitar; I post this rather to hope to know how it would go if I did. Perhaps the fumes would kill me, but it ought to work in theory.

It does though work wonderfully as an overnight method to repair worn patches, chips and scratches, etc. and I find that it has been mentioned before on this forum:

http://www.woodworkforums.ubeaut.com...ate#post243194

-- RH.