Spraying lacquer

[eisbaer]

Hi everyone,

So as many of you will have seen, I like to try different finishes from time to time. I've been considering spraying lacquer instead of dipping to try and get a more even finish.

I've never done spray finishing before and I'm not sure where to start. The precat lacquer I dip with is fine for spraying but I don't own the apparatus required.

Does anyone have any suggestions regarding compressor, airbrush and mix ratio? This will be used initially for pens but eventually many things.

[plantagenon]

An air brush would be the way to go as a normal spray gun would have far too much over spray and power. The air brush should come with instructions and a mixer so you get the ratios right between the lacquer and the thinner.

Good luck, it won't be easy as you don't have a flat surface and you will need to rotate the blank at an even speed to get a consistent coat. Try the guys in furniture making on this forum as some of them might use spray guns.

[Pariss]

Hard to beat a glassy CA finish. I enjoy trying a variety of finishes for variouse woodworking projects, but as far as pen making goes, there really are only a few that can logically be used for timber pens. If you want HARD high gloss then CA or Polly is the go. If you want a natural, close to the wood satin finish (that will last a long time), then EEE compound & Shellawax + a final coat of Traditional Wax is gorgeous and quick and easy. Pens are not ornamental, they will be used by people with greasy sweaty hands, chucked around on a desk, dropped on the floor, and generally given a rough life. Spray lacquer won't last very long in these situations. It's best used on more ornamental type projects. Anyway, that's my take on the subject of finishes. Have fun :2tsup:

[eisbaer]

I've tried CA to death and I'm not keen to revisit it. I simply can't get it to work consistently. When it works it's great, but I can't get it to work even half the time.:((

Lacquer has been the best finish I've used so far. It's durable and easy to apply. I've dipped and sprayed it from a can and it always works well. What little problems I've had have been easy to fix without starting the finish from scratch.

Poly isn't bad, but I use the WOP and I find it has a very thin consistency and requires many coats to get a good depth. For whatever reason, although it is thin I find it takes longer to get touch dry (ie- how long until I can put more layers on). So basically I can apply a lacquer finish and have it look good far quicker than WOP. I do find WOP gives a more satin finish though and that's good for some things. I use the high gloss but it never goes that glossy and has little depth.:?

Friction polishes leave a temporary coating but I'm still trying to crack the formula for lacquer based friction polishes to make something a little tougher. Mixed results so far. I did an olive pen and it wore away, but it hasn't worn off the leatherwood and it may be to do with the high oil content of the olive. Still working on this one and if I do find a formula that works I'll be sure to share it.

I know spraying a cylinder isn't easy but I've done it with a can of mirotone and that didn't have the rate of control I get from an airbrush so it seems to make the most sense. It'll also get used for bigger things later. I'd use cans again but to be honest it's expensive and wasteful. Large cone of spray and a heavy spray means I probably used more than I need.

I'm not sure what PSI rating I should be looking at though. Hobby compressors are up to about 30PSI but I don't know if that'll do it. If anyone has tried I'm all ears. :)

[bruceh]

G'day Eisbaer,
spraying lacquer really is very easy . Any air compressor will do even one of those cheapies from Super Cheap. I use a HVLP gravity fed gun with a 1.4 - 1.7mm nozzle and run the air pressure at 1.5 bar . As far as thinning the lacquer start with 2 parts lac. to 1 part thinners as a start , if needed you can go 50 - 50. This will be a good starting point and can be altered to suit. I normally thread a few blanks on some 6mm dowel and give about 6 light coats in fairly quick succession then allow to dry overnight before cutting back with micro mesh . The end result is a highly polished blank that looks equal to CA without some of the problems but not quite as durable .
Hope this helps.
Cheers Bruce.

Wood N Workshop

[eisbaer]

Hi Bruce,

Thanks for the advice. I've seen your pens many times and they're always finished beautifully.

I've been looking on ebay at some hobby compressors for under $100 and found a few that will do adequate pressure. I use luxlac 100% gloss for dipping and I'll use the same for spray. I've been told 50/50 is the way to do it by a few people now. I'm going to have a better look at airbrushes and I'll take your advice on size.

I've been trying to design a basic rotisserie to turn the pens slowly as I spray because my lathe simply can't go slow enough. So far I think I might be able to do 4 at a time on one bar without breaking the bank. If I get this all set up soon I'll get photos up.

[Robson Valley]

In a past life, I worked for 20+ yrs in theatrical stagecraft, ballet theater no less.

I run and ran several airbrushes with a regulator and a 1/2 bottle of 3000psi nitrogen from a welder's supply. Everything from costumes and props to makeup.

Spray a cylinder? No problems. Score a crappy old record turntable. Can you young punks remember 331/3? You can spray a light coat, over and over, until you get bored. With a big piece to work on, you have to twist the job to help the turntable to get moving. Couple of twists and it sails along.

[Dengue]

Please excuse my ignorance, but what is CA and WOP?

What finishes do you recommend for jarrah boxes?

[cookie48]

I have used spray on floor laquer. But then again I have a metal lathe that I turn down to about 50 rpm. Place the blanks on a threaded rod with spacers in between and they seem to be ok. Have not ried to sell any tho. Just for experimentation on my part.

[eisbaer]

I like the turntable idea but I've already got a small motor to do the rotation so I'm sweet there.

Wop is wipe on poly.

Ca is cyanoacrylate (super glue)

I've designed a basic machine to spin the blanks slowly for spraying and I should be able to variably adjust the speed. I'll need to build a frame for it and then start saving for a compressor.

Sent from my HTC Desire using Tapatalk

[Paulphot]

Model makers use small airbrushes on aerosole cans for small detail work. They thin down their paint and spray it for smooth even coverage. Maybe something like that would be good to test the theory without the outlay for a compressor and spray gun etc.

[eisbaer]

That's a good idea. I've been looking at small hobby compressors for model painting etc and they might do the trick for pens also. It doesn't cost much money to get one of those.

[plantagenon]

eisbaer (http://www.woodworkforums.com/members/17081-eisbaer/)

How long do you let the blanks hang to dry before the next dipping with PPG?

[eisbaer]

About an hour in summer.