Painting help needed ASAP

[nizm0zed]

Ok, so im painting my car (and learning as i go) and i have got all the colour down nicely.

I began blending the colour and clear together and spraying coats of that, first coat at 70% colour 30% clear, second coat at 40% colour 60 % clear.

At that point i ran out of clear (K&H acrylic clear coat)

I happened to be going past supercrap today so i dropped in and grabbed some of their clearcoat, Acrylic Clear by 3M.

I am allready using the premium gloss 3M thinners so i didnt think it'd be an issue changing to their brand clearcoat.

No matter what i do, i get massive overspray from the 3M clear, the K&H stuff didnt do this?

It looks like a heavy white dust had settled over the car.

I can pass over the panel in one direction and get a light mist at the edges of the fan, once i pass back the edges get heavy with overspray.

I have tried upping the pressure at the gun, increasing the fluid delivery, holding the gun closer, closing down the fan pattern and have resorted to skimming a light coat of straight thinners over the body once i have finished painting. It seems to be melting the overspray into the surrounding paint.

 

Has anyone had similar problems with the 3M product? Im seriously considering taking it back and getting my money back I'll go buy the K&H stuff....

Can any of the experienced painters maybe tell me if there is a better way to reduce the overspray?

Im painting in my garage, with the door open and the car sitting just out of the door.

[Sirpent]

Alan,

 

The amount of thinners you are using in the mix isn't enough.

 

Whats happening is that the thinners in the mix is basically evaporating as it hits the air of the gun fan and the clear is instantly turning into what I call fairy floss.

 

Also,

 

You don't mix clear and color together ! especially at the end as what will happen is that the color will be suspended in the final coat, when you later attempt to wet rub and polish it you will end up with a patchwork blotchy finish.

 

This is what i recommend.

 

#1 let what you have painted dry out in the sun for as many days as you can leave it there. you will know when it's 100% cured as the smell of solvent from the paintwork will disappear.

 

#2 By doing this, any major shrinkage in the bodywork will become evident, the paint you have put down will become a barrier for the next stage which is to wet soft block the paint you already laid down with 600 grit wet and dry, use clean water which you change regularly with dish washing liquid, don't let the paper develop scaling from the paint you rub down, use long strokes NOT CIRCULAR motion.

 

#3 Re-mask the car and prep wash it down.

 

#4 Mix your color up, put down single DRY coats meaning if you can see wet patches or tiger strips appear on your overlaps its too wet, the finish should be uniform, let the color flash dry then apply another coat, let this flash dry, then finally apply the final color coat, this should be done by holding the gun twice the normal distance from the panel you are spraying on a very wide fan setting, what will happen is that you will end up with an extremely dry but extremely uniform finish of color.

 

#5 Let this dry for an hour, go have a beer and a bite to each, come back and using the gun with air only, start a blow down of the body to eliminate any dust that may have settled.

 

#6 The first coat of clear should be very dry so as not to burn into the color coat, Lay down one coat only and allow to totally flash dry, repeat this 2 more times the same way, it will look SH*T but what you are doing is creating an impregnable boundary.

 

#7 Now apply the first WET coat, slow overlapping clear coat as you would usually mix it and let this flash dry for 20 minutes.

 

#8 Now apply the same mix but as soon as you finish the first coat on a panel or side, start again over it, this will really flatten the clear coat some what.

 

#9 I like to do the double coat at least 2 times, sometimes 3 so repeat but leave time in between 15-20 minutes.

 

#10 Now the final coat, this will hit down the orange peel all the way. Its called a flow coat, 75-80% thinners and 20% clear, as in the double coat apply the same way, allow to flash for 15 minutes then do it again, if you have done this right you should end up with a finish you only need to compound buff.

 

I Would suggest taking a panel and following these steps as a practice run, you will quickly see how it pans out and this will give you all the confidence in the world.

 

Cheers

 

John

[nizm0zed]

yep, fairy floss, a VERY good way of describing it....

Interesting that you say that there is not enough thinners, i can see how it would cause that now you explain it, but i did mix it according to what was written on the can.

I guess you cant put much faith in that huh....

 

Ok, i have a spare bonnet that i use to set up my gun, i'll get onto that tomorrow and practice what you have mentioned.

 

Its such an awesome forum to be able to ask for help like this and actually have knowledgeable people help out.

Im in no rush to finish this, so i have plenty of time to let it sit and dry between coats.

 

 

+1 karma for you my friend, you are truly a gentleman...

 

 

(fwiw, its REALLY hard to find a good tutorial on google, probably due to so many different types of paint?)

[Sirpent]

Thanks Buddy and all the best,

 

However, dont use K&H, for base coat colors any brand will do but when it comes to clears and particularly thinners only use top shelf stuff, clears and thinners tend to deteriate quickly if they are poor qaulity.

 

When I used to spray acrylics I would only use Spartan products produced by Wattyl, they were in my opinion superior to all the rest, I believe spartan is now sold under the BASF Wattyl Auto brand.

 

Invest a bit more for far less headaches down the track.

 

Cheers

 

John

[nizm0zed]

the base coat colour im using is Dupont Lucite 400 (or something like that...)

 

I took your suggestion of more thinners in the clear, and tried a test run on a spare panel, it still fairy flosses like nothing else.

Im pretty convinced that the 3M clear acrylic is just plain s&^%.

So, time and cash permitting, i'll be dropping past the paint shop to get some real clear coat.

[peter t]

As usual John you are a wealth of knowledge when it comes to painting. Should put all your tips in one thread. Thanks once again.