Words of Wis-Dumb: Working with Fiberglass and Prep for Paint

[BobbyB]

Its kinda expensive but DuPont 3812 enamel reducer does a good job cleaning. Leaves no residue and dries very quick.
Bob

[LCD Gauges]

Yes, of course you can see the cubicle, but don't expect a "paint booth" by any stretch of the definition.
It's essentially 4mil plastic hung from the garage door rails, and stapled/taped at the seams. I'll
have to improve the filtration once the primer is ready to spray.

Ron, thanks for the tips. I found some great info about paint guns, and primers tonight.
These guys appear to know their stuff, and have made me realize there's much more to learn
before I begin the primer prep stage.

http://m.youtube.com/watch?v=Bu3KxqH7mM0
http://m.youtube.com/watch?v=DXdrcsBeEcA
http://m.youtube.com/watch?v=BUjmqdoqxL4

[LCD Gauges]

Thanksgiving Weekend here in the North, so happy THXGVG to all.

Talked to my dad last night about the car, and painting. Since we spoke last, he met with his painter buddy again.
He relayed some interesting topics that I'd like to share with everyone. I'm not certain that these techniques, and tips
are the best methods, but it's more to research.

He said I should use a tinted primer to match the final colour. It will make it easier to cover the primer with less paint. Makes sense.


Use one, or two layers of paint over primer. More layers of paint is worse...hmmm? Not sure about this one. He is talking about water based paint.


Water based paint. Good, better, best? I'll need to check my options, and pros/cons.


800 grit blocking after 2K primer has been laid down. Sure, why not?

He says Black is easiest to paint, red is the most difficult. Not sure?

In any case, his friend wants to see the car, and would like to "shoot it" for me. We're tossing around some ideas to get the
car into a booth for the primer, and paint stage.

So much for me waiting 5 years to get it done, "pro"?

Back with more about pros/cons later.

[Taz Rules]

Thanksgiving Weekend here in the North, so happy THXGVG to all.

Back atcha, Tino

He said I should use a tinted primer to match the final colour. It will make it easier to cover the primer with less paint. Makes sense.

Yes. You can even use gray primer, but tint it to the correct value. BASF Glasurit has levels from 0 (black) to 7 (white), with 6 shades of gray in between. PPG has a similar system. Or you can tint your primer to colour, but that gets a bit more pricey.

Either way, this has two benefits...1. Better coverage with less paint, and 2. if you get a rock chip that goes down to the primer, it won't stick out on your finish like a sore thumb.



Use one, or two layers of paint over primer. More layers of paint is worse...hmmm? Not sure about this one. He is talking about water based paint.[/QUOTE]
Your colour coat should be sprayed to a semi wet coat, and repeat as many coats as necessary to cover. Use a spray out card with white and black sections as a guide. When you can't see the white/black demarcation on the card, you have coverage. Sometimes you can do it in two coats, such as with a heavy silver or black, other times it may take 4 coats such as with a white or yellow.

Follow with at least two coats of clear, three or four if you want to colour sand and polish.

Water based paint. Good, better, best? I'll need to check my options, and pros/cons.

Solvent borne paint is currently illegal in Canada due to VOC regulations. So you have to go with water borne colour and urethane clearcoats, and spray them with HVLP or RP technology spray guns.

RM is just (re)releasing the Onyx line, which is a VOC compliant solvent borne colour coat, but its performance is not as good as water bornes.

I've sprayed both, solvent and water, and my observation is that water borne paints lay much better metallics, because the flakes don't "float" and lay flat. Some people say that solvent has more brilliant colour, but I disagree. The big advantage of solvent is the ability to control your flash time and maintain a wet edge, especially with a complete paint job as opposed to a repair.

Overall, there's nothing wrong with water, in fact, I actually prefer to spray it.

800 grit blocking after 2K primer has been laid down. Sure, why not?

Thats a bit fine. Some body shops go to 400 to smooth primer. I do 600 for colour coats, and if I'm doing a blend, I'll go 800 on the BLEND AREA ONLY (where no colour, only clear will be sprayed.)

800 won't hurt, but its a bit of overkill. Just make sure you work your way up using progressively finer grits...

Block with 240 to straighten,
Guide coat (with powder) and block again with 320 to clear 240 scratch marks and MINOR straightening,
Guide coat (with powder) and Buzz or hand block with 400 to clear 320 scratch marks,
Guide coat (with powder) and Buzz with 600 to clear 400 scratch marks,
then if necessary, buzz with 800 to clear 600 scratch marks.

DO NOT SAND BETWEEN COLOUR AND CLEAR COATS!!!! Any pearl or metallic will give you a dark black smear!

He says Black is easiest to paint, red is the most difficult. Not sure?

Candies (tri-coats in modern parlance) are the most difficult, due to "tiger striping". Metallics and pearls are a bear if you don't follow the sanding procedure above, because the flakes will "track" into the sanding marks.
I've done reds and blacks. Black is very fussy with making sure you have proper prep. Any wave will show. Personally, I find white pearls the worst/most difficult.

In any case, his friend wants to see the car, and would like to "shoot it" for me. We're tossing around some ideas to get the
car into a booth for the primer, and paint stage.

So much for me waiting 5 years to get it done, "pro"?

Back with more about pros/cons later.

Big Pro!!!!!
Primers and paints...there are a lot of very good brands out there...
RM/Glasurit, PPG, Sikkens, DuPont...any of these will work very well. I would caution you to pick one system and stick with it from first primer through to clear coat. Mixing and matching brands can lead to problems as they are not always compatible.

Also, a little bit of flex agent in the clear will give it some added flexibility and cut down on rock chips. Just a little hint.

[LCD Gauges]

More reading for those wanting to learn more about body prep/primer/paint:

http://www.carsdirect.com/car-mainte...t-the-pros-use

Thanks Taz for the awesome reply too!

I've taken some tips from each of you, and have applied them. I'll let you know how Vidal's procedure works for the pin-hole repairs that I'm
currently fixing. Should have pictures in a day, or two.