oz Spray Finishin techniques??? any advice?

General Discussion
1

I’m playin with different automotive two part clear coats for some time now

I do a lot of art ontop of the glass.

The most recent stuff im playin w/is extremely hard and durable yet expensive…

Im tryin to figure out the best finishin technique which i can only spray one coat without havin to sand+buff the hell outa it too,

basically i need a quick production method to just scuff it up that still looks even.

I know this sounds dumb as hell and basic, but ive had a hell a time playin w/this stuff. Am i bein ridiculous lookin for an easy method of doin this, or is the only way to spray multiple coats, and sand and buff out to 600grit. Im use to linear scotch brite with polish solutions on weaker clearcoats, and ive had good results, just nothin decent time wise thats still durable?

I know everyone has there own secrets, Just curious on playin with different techniques!

Cheers!

AJW

2

Not sure if i’m understanding you right, but heres what I do -

I spray 2 coats of 2Pac automotive clear, waiting 5 mins between the coats, to give it time to flash off.

The next day I wet sand with 1500 grit, then use a cutting paste.

I know you said you didn’t want to sand and buff, but it’s only about 1/2 an hors work.

Getting a perfect gloss finish off the gun is what makes a proffesional car painter a proffesional…

You can do it, but getting it perfect everytime is bloody hard. easier to sand then cut and polish.

Talk to the guys at your local auto paint supplys, they’ll set you on the right track.

3

G’day Ajw,

If you really want to protect your art a finish coat is the way to go.

Or do your art work on the foam, saves the weight of an extra coat of resin, but if you make a mistake on the foam she’s there forever.

Finished of a racing mal with next day acrylic concrete sealer afew months ago, hard as nails but I still needed to cut and polish, and I only used it because it was left over from a driveway I had done.

On shortboards I use the Protec clear acrylic lacquer, couple of coats, then rub down with #1200 (600 then 1200 if need be).

If you are used to sanding surfboards this rubbing down is nothing , even dare I say , a joy!

Good luck

Daren

4

kksurf-

thanks… thats pretty much what ive been doin, just wasnt sure if there was a better method.

I think i need to practice more on my gun technique. Do you ever lightly sand in between coats, just

to get that last coat to lay out smoother?

Also what does the cutting paste do? buff it out, or help w/ the sandjob. Ive been talkin w/ the automotive guys,

they pretty much told, me i need to be doin at least 3 coats, then just sand it all flat while taken it to higher grits.

I think im just nervous of sandin off the clear? what grit are u startin with?

thanks again!

5

Howzit Entity, Actually you can sand a bad paint job off the foam, done it more than once. Doesn’t take much sanding to remove it. Aloha,Kokua

6

im a spray painter and it is all about technique! and your gun and compressor!

we have a spray machine where i work that i could put any lacquer or resin through! i can get 2 coats on stuff with it with no imperfection light sand with 320 in between, but the system costs!!

with a normal gun it just takes more coats 3-4 and a light 320 sand between on 3 then leave to fully cure and wet sand and buff out!! to get really clear no scratches your sand on the hot coat needs to be real good!! or scratches will show. gloss resin fills these in so less sanding on the hotcoat, but then glossing takes just as long to do!!!

7

Paul,

have you ever worked with a two part paint, Imron? There is a clear version of it that may work well on surfboards. It was considered expensive in the late 70’s, and was used on high end custom, and exotic cars, as the clear coat over color. Any info? Anyone else know anything about it? Thanks guys.

8

Bill, Imron was some tough stuff, not sure if its still around, but it would be a great clear for surfboards. Saw it used on a lot of boats and small aircraft… Lots of name brand two, or three part auto clears are good for boards, especially the faster drying ones made for spot and panel repair. They buff good to, but once you get the hang of it, you wont need to.

Scott

9

ajw,

I spray 2 coats, but I sort of cheat a bit, i’m not sure if it’s good spray painting technique, but it works for me…

I mix up about 90 ml, and spray a light tack coat, wait 1 minute, then spray another coat, heavier than the last.

I clean out my gun, and wait 5 - 10 minutes.

Then I spray another 90 ml, doing it in two passes with a minute in between as before.

So I only do two spray sessions, but I suppose you could call it 4 slightly lighter coats?

I find you could spray the whole 90 ml in one pass, but it’s theres the risk of getting sags and runs then.

I don’t think you can get a perfect shine straight off the gun if you do it my way, as it goes on t0o dry, giving a dusty finish.

But i’m happy with it, it’s safe(no runs), gives good build, and the cut ‘n’ polish gives the ultimate shine.

I use a fast hardener as well.

The next day when it’s dry, I wet sand, with lots of water, with only 1500.

If I happen to have done a really crap job of spraying, I might run over it with 1000 grit (wet) before the 1500.

I’ve never sanded through, you should have no problems if you sand by hand with those fine grits.

Then the cutting paste - this takes out the micro scatches/hazyness that the 1500 leaves, and you get the full shine after that.

Kit

10

we use some 2 part a/c lacquer of tables at work that is v expensive and comes out nice and thick! what would usually take 5 coats on a table with a normal gun the system we run can do it in 2! and is perfect clear gloss. and is heat proof and polishable. been meaning to take a board into work and try it out.

11

You might look for the brand name U-Pol, clear. Its a UK auto paint product so it might be in Aus. Its one part, less expensive than 2 part, less toxic than 2 part, goes on excellent. I’ve used it once, turned out great. Spray, wet sand with 1500, power rub out with medium or fine compound, perfect job. I had put up a more detailed post of how it went about a month ago.

12

I’ve not tried it, but I assume that like all of the methods above, you’ll need a dust free drying environment. As opposed to say, my garage. ha.

My next project is a balsa blank and I would love to gloss it. I’ll just keep reading here. thx.

13

Been spraying 2 pac for a few years and there is quite a bit of info on getting good results online. There are automotive painter forums that you can search and ask questions just like Swaylocks.

A couple of must haves is an oil and water seperator for your compressor. Fish eyes and all the other problems from a bad air supply can be a nightmare.

Get a good gun. The crappy cheap ones are hard to adjust.

Your prep work is critical. The surface has to be smooth if you want a smooth finish.

Another trick is good lighting. It is important to see what you’ve sprayed so that you are making good passes. Just don’t blast it on and hope for the best. I like to see the coat shine and to make good passes that cover the whole project. How you hold your gun and the way you apply the paint is critical. It’s like watching a good laminator, the stance and dance that happens is for a reason.

The last one is to know your product. Temperature, humidity, proper reduction, gun settings all make a huge difference in your results. Unfortunately the 2 pac is very expensive but you just have to do it. The saving grace is that most of them can be fixed with good sanding and buffing. Gives you time to figure out how you screwed up the spray job as you polish out your mistakes.

14

DMP

  • appreciate your input !

thats the ticket good prepwork, and i think my main trouble has been from a poor compressor filter… definitely could be

affecting my sprays.

-As for the U-pol clears, ive heard good stuff about those, and definitely need to check it out. My best results were from a

european Transtar clear, forget the exact name,very expensive, but good shit!

I just still need to play around w/different grits, and prep techniques! thanks

15

Your welcome.

Sometimes the elusive prefect spray job just does not exist. Most high end places just try to concentrate on getting an even application of the product. Too many variables to worry about getting a perfect spray job. They know that they will be color sanding and buffing to get the desired finish.

I can spray the 2 pac but for something as simple as a surfboard I’ve been using water based floor finish polyurethane. It levels way better than the 2 pac and won’t kill you.

I hope you understand that there is no filter that I know of that will protect you from the isocyanates. You are supposed to be using a forced air setup or spray in a down draft booth.

16

im using a 2 pac called Ameron

its great stuff

i do my spray in one coat with the board flat and put it under a dust tent

i have a small fan extracting the fumes out the window

the last couple of boards were a pretty good finish straight out of the gun