Nitrocelous lacquer
I am about to paint a trunk with Nitrocelous lacquer which I have never used. How long before I can cut it with wet paper and then buff??
When it no longer gives off any smell. You can lightly sand a test panel and if the test panel doesn't clog the wet or dry paper, it is ready to finish the trunk. I painted a lot of cars with nitrocellulose lacquer in California until they banned it and then I switched to Centuri. I thin it more each time and on the 15th coat I sometimes used only four table spoons full of pigment and the rest was lacquer thinner. Spray it on real wet and you will not have to sand it at all. Let it dry between coats. I would put a coat on every night at about 9:00. I used one gallon of British Racing Green -Dark - paint and four gallons of thinner that cost .80 cents a gallon back in those days on our 4.2 1966 Jaguar back in 1980. As I stated before, I used four table spoons of paint and filled the cup with slow thinner on the last five or six coats. I did not have to sand the surfaces. The wet coats simply smoothed out the coats below. They don't allow it today because we have too many children breathing in the fumes so we have to use a water type paint and spend thousands of dollars to paint a car rather than do it yourself for $50.00. Change for the sake of change sometimes stinks worse than the lacquer thinner does.
We painted a friend's 1970 Maverick gloss black using nitrocellulose lacquer in 1977. The first time we painted it he tried to wet sand about two days later. The paint balled up in the sandpaper and we had to sand the entire car and shoot another coat.
Second time he waited about two weeks. It was easy to wet sand with 1000 grit, 1500 grit and then buff. However it was still a 1970 Maverick when we got done.
Royce:
"However it was still a 1970 Maverick when we got done."
LMAO ... How true! :-)
If sanding is required put dish soap in a bucket
and fill with water dip the sanding paper into it. This will help stop paint from balling up in
the sandpaper.
Are you guys sure you are not talking about Acrylic Lacquer? It can take 2 -3 days to be dry enough to rub if conditions are not right (temperature, time between coats)
The NC lacquer we had in Australia dried within hours. In the shop we sprayed it before lunch polished it if needed mid afternoon, if you let it dry more than 24 hours it was so hard if you needed to remove a fault you rubbed it out with W&d paper and flowed another ultra thin coat or straight thinner over the surface. the paint was so hard it took forever to compound out the fine scratches, remelting the NC with solvent flowed out the scratches.
One big myth that has always been around is the need for huge number of coats of NC or acrylic lacquer. This is because the surface is not prepared well enough and the numerous extra coats are used to fill and level the surface. If you use the undercoats to do this (what they are designed for) you will fill faults better and it will be cheaper than using color. Extra coats and you run the risk of the paint cracking and crazing later on.
All GM cars sold here till 1963 used NC lacquer. The standard was 5 coats only. Repairing or respraying required 3 coats mixed 50/50 with thinner wait 1 hour, rub with 600 grit W&D paper (wet) then follow up with 2 coats thinned 80/20 (80 parts thinner/20 paint)or thinner. If the surface primer had been leveled before color then this was more than enough paint to get a full gloss finish. when I first started as an apprentice the old painter only hand buffed finished color. It wasn't until Acrylic Lacquer which is far slower drying and has less gloss that we purchased a buff machine.
Lacquers are good easy paints to use and have one big advantage besides being fast drying, they can be spot repaired, a small mark and just that area can be rubbed filled and resprayed without any evidence of it being done. Great when the car has a huge roof or other panel and the damage is dime sized.
A couple of other points, for best results you need a spray gun set up to spray lacquer, ones used for Centari type paint spray it too dry and sandy. The NC ones have a larger nozzle to let out far more paint as it dries so fast the air evaporates the solvent before it reaches the surface.
Use only the correct primers and solvents and instructions for the paint recommended by the manufacturer don't take the guys behind the counters advice. I'm sure the information is available for the brand you use on the internet.
The reason lacquers are banned or are to be banned is the fact they need so much solvents. At least 50% plus just to get it out of the spray gun all of which plus what was in the thick paint in the tin is evaporated into the air. The new paints use less than 10% some virtually no solvent.
As Dale suggests you can use soap to make the wet paper slippery when rubbing, one trade secret which is even better for acrylic Lacquer is to rub it with mineral turps, its so good you can rub the AC lacquer minutes after its applied once it has stopped being wet. It dries off and water does not need to be dried out. It allows you to fix problems in a jiffy and continue on spraying.