DarylJ

OK...so if its all covered, and you have enough build that it's smooth (or even close) you likely need a sealer (unless what you had was primer/sealer).

Are you doing a base/clear job, or a single stage?

Calmchaos

base/clear
It was just a primer. If a sealer is a good idea I'll get some. I assume it goes on right over the primer?

DarylJ

Yes. From my research, a sealer or primer/sealer is highly recommended so that you don't end up seeing bodywork/old paint/etc through your base coat. But again, you need to look at the spec sheet for you base coat, and make sure you are doing what is recommended and putting an appropriate coating below it.

And make sure it looks perfect once it's primed/sealer. Any imperfections after this point will only look WORSE once the paint is on. Don't do what I did years ago and talk yourself into thinking that the color coats will cover it up. Fix it now, while you can.

Calmchaos

Oh yeah... I know paint isn't designed to hide anything. My dad and I spend almost a month prepping the car trying to make it perfect.

The base coat doesn't say anything about a sealer. Only primer.

DarylJ

In that case, do what it says. I've yet to hear of even the most experienced painter "outsmart" the chemists that make these paints.

There was a thread on some board a while back with some old school guys talking about sanding their color coat (on a base/clear job). Apparently that's what you used to do. Most new base/clear systems specifically tell you NOT to do this. The guy tried half a panel one way, and half the other. Let it dry, scratched an X across the two applications. Put duct tape on it, smashed it down real hard, and ripped it off. Only the stuff that was applied AGAINST the recommendations came off.

Calmchaos

Hey,
My dad just put on the 1st coat of color and it looks pretty good.
But what do I do to the color coat to make it smooth?
The color is a metallic, should I wet sand with 1000+ grit sandpaper?

I have rubbing compound for after the clear.

Thanks!

jmd_forest

By "smooth" I'm assuming you mean glossy. The basecoats I've painted all go on with a somewhat matt finish. The smooth, glossy look is provided by the clear coat. It depende on the specific paint you are applying, but all the base/clear paints I've applied require the clear to be applied within a few (15 - 30 ) minutes of the basecoat.

If you have runs or orange peel in the basecoat, they need to be allowed to fully cure (24 hours), sanded out, and another layer of basecoat applied before the clear coat. If the basecoat looks and feels like sandpaper, you are probably using too low a temp ( or too fast) of a reducer and will need to sand out the basecoat and apply a new layer of basecoat before the clear.

A good basecoat will have no runs, sags, "orange peel", or pebbled/sandpaper finish. Do NOT apply the clearcoat unless your basecoat is acceptable.

When all else fails, read and follow the instructions for your specific paint.

jmd_forest

944-LT1

You want to use an epoxy primer first for the substrate (this is good for bare steel and any filler you may have used), then the primer you have preferably 3 coats and, if needed, a guide coat. Then a sealer (if no sealer, the basecoat can seap into the primer and cause the color fade or discolor within a few months), then base and clearcoat X4.

I used one gallon to put 3 coats + 1 guide coat on my 944. It was thinned 50%. Cheap stuff so no biggie but if you use more than a gallon of base....uh, something may not be right with your gun. Haha.

The manufacturer of YOUR paint should have an online tech sheet that explains how each unit is to be mixed and at what psi and temp it should be sprayed. 60 degrees is pretty cool. Usually good to do it at 70-75. But that wont be a big deal. The guy who sold the paint should have given you a reducer for cooler conditions.

For cleaning the gun, loosen the gun tip cap and then the pot cap and pour in a cup of lacquer thinner W/Gloves and googles of course and pull the trigger. The thinner should percolate in the cup and clean the venturis out completely. Its quick and easy. You should jump over to http://www.leopardsystems.com/paintucationforum/ for more tips and tricks. Absolutely priceless information.

What tip is on your gun? I have a 1.4. Many people forget to check this and have a tip for thicker paints such as latex and when spraying thin paints like stain and automotie paints, the paint just flys by.

Hope this helps alittle.

DarylJ

You've already blown it if you're waiting around for an answer. Base/clear goes on continuous in under 4 hours, depending on how many coats your doing. There is NO STOPPING (other than a few minutes to wait for flash).

As far as your question about sanding:

Yes, base coat goes on to a matte finish. And the flash times are important because the clear coat actually soaks into the base coat a bit. After the second coat of clear, it will be shiny.

If you are saying that you have nibs and crap sticking out of the paint, then you're spraying too dry. Scuff, test on something else to figure out how to set your gun, and start over on the car.

And I specifically related a story to you about not following spec sheets a few posts above. It even happened to be about trying to outsmart the chemists that formulate automotive paint and sanding when they yell you not to.

xsboost90

this is the most confusing thread ive ever read....

What kind of primer are you using. If you are using Laquer primer it will be cut w/ laquer thinner. I personally would not use Laquer primer because that is very old technology. Sealers are only to be used once the car is in primer and ready to spray- you put a coat of sealer on then spray the paint over that. You do not want dry sealer cuz its hard to sand and not meant for that-unless you are just sealing the car to hold water out and its going to be in primer for a long time. If you want to spray the car w/ eurethane paint, you would ideally want to use eurethane primer which holds shrinking alot better than laquer and is actually cheaper. Most eurethane primers are cut 4:1 paint to activator.

Then your coats etc on eurethane paint depend on the system you use. Eurethane paints are usually cut w/ an activator specifically for that basecoat 4:1 or 3:1. Most systems you would need about 2/3 of a gallon to spray a 944 basecoat- sometimes less. You would put about 3-5 coats on to cover completely but it really depends on how heavy you are putting them on. Fog the first coat so that it is"tinted" red and then get heavier from there. Eurethane paints flash off pretty quick around 70 degrees so you can go back and wetsand out mistakes after it dries w/ some 500-1000 grit wetdry sandpaper and some water. Once the car is all one color, i usually put one more coat over everything just to make sure i dont have any spots that i missed- make sure you get under the edges of the wheel wells, lower rocker panels etc- nothing worse than getting finished and finding primer along an edge.

Most eurethane paints only allow TWO coats of clear. These are usually cut 2:1,3:1,4:1 and sometimes also require a reducer. NONE require laquer thinner so dont substitute! Both coats go on pretty solid and wet. IF you put the first coat on, allow to dry about 15 minutes and check by putting your finger on some tape or something on the car- if the clear is "stringy" when you pull your finger away its ready for the final coat. Most systems you DO NOT want more than two heavy coats of eurethane clear. Ive tested this and ended up w/ runny cars before. The second coat can be nice and heavy-not too heavy- but lay it out nice and glossy then stop there. The third coat is too heavy and will run like crazy if you try.

DarylJ

All due respect Dan, but I think it's time to go back to the paint shop for some more recent experience. We're talking about Urethane paints. Since this guy doesn't know what brand of paint he has, I am assuming it's something modern and typical (DuPont ChromaBase or ChromaPremier, Sherwin Williams 9000, etc.). My advice is pretty much quoting the DuPont Chroma System tech manuals, which are available for all to see right here:
http://www.performancecoatings.dupon...le=DirectLogin

I understand where you're coming from - I painted the way you suggest 10 or 15 years ago. Now I'm back on another painting binge and find the rules have changed because the paints available now are hugely different than they used to be. They are easier to apply, but much more finicky about the materials you use and how they are applied. The base/clear systems are MUCH different than they used to be with flash times, sanding base coats, etc. primarily because doing it that was was TOO EXPENSIVE. Now they are formulated for a volume paint shop to be able to quickly apply them and have them look good. No waiting to sand base coats, no force drying between coats, etc.

I'm not claiming to be an expert, but I've done a lot of research on this, and have about 10 cars under my belt. The first one came out like a orange. The rest have been better and better. Mostly because I followed the instructions.

Calmchaos

I FINALLY found the instructions for this base....
It says I may sand anytime after 1 hour... then I must apply more base coat.
The the clear goes on no earlier than 30minutes later but no later than 24 hours.

BTW the paint is deltron 2000/DBC

DarylJ

That's great - now you know what to do. And nice that you can go up to 24 hours before clear on that system. Just make sure you have a really clean environment if you're going to split it up into 2 days - you don't want to clear coat dust and crap into your paint.

Oh...and on sanding your final color coat - I just found the perfect example on my car as I was d/a'ing it. (Yeah - putting an old laptop in the garage is sometimes bad - you waste time on Rennlist when you should be working).

Here's the top of my door (which was repainted at some point by the PO):


And near the door handle. You can see where it is peeling all around the handle gasket (removed). Things look the same around the trim strips that were on the doors (not putting them back on):



So, as I was saying, don't sand a color coat before clearing. It's a really bad idea. It might look fine when you're done, but you WILL be sorry later. (Unless your paint system specifically says that it's ok)

Calmchaos

yeah the last color coat is going on now... and will not be sanded before applying the clear.

DarylJ

Pics!