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Sat Nov 01, 2008 7:05 pm

ok so im using a primer called "Transtar 2K Quick Prime"
I have a gun from a comany called Vapor.
It is an HVLP gun with a 1.8 tip
the paint can says to spray at 10 psi
that seemed really low to me but I tried it om a peice of carboard taped to the wall.
all it did way sputter a little bit so i played with the pressure until it made a fan, which was at 50 psi which is the gun's max

when I sprayed the primer it went on very rough
i thought primer was supposed to go on very smooth.
when it was dry it was very rough and had lots of little specs in it

What is going on! PLEASE HELP!

Sat Nov 01, 2008 7:30 pm

Did you reduce the primer before spraying? If it's to thick it will do just what you described.

Sat Nov 01, 2008 7:38 pm

I have never used that product so I can only make these general recommendations.
1. As previously suggested...did you add the reducer?
2. Did you screen the paint after you mixed the in the reducer as you were pouring it into the cup?
3. 10 psi is way too low.

Sat Nov 01, 2008 7:47 pm

its probably the reducer, that makes sense
the guy who sold it to me didnt put primer in the box
I didnt pay for the reducer or anything, but I didnt realize I didnt get any until I got home
I guess Ill go pick some up, thanks a ton guys
I guess ill have to spend a little more time sanding before I spray more primer.

Sat Nov 01, 2008 8:12 pm

can I use the reducer that came with my basecoat?
it is a urethane grade medium reducer

Sat Nov 01, 2008 9:10 pm

It likely means 10psi at the cap(although I have never seen it suggested at cap pressure). You will probably have 35-45psi entering the gun, 7-10 exiting.

When I was at PPG for a paint clinic they were showing all of the different pressures throughout the system.

And IIRC transstar makes really bad products. You may want to spend a little more on higher quality materials. Just a heads up, but f you'v done your reading and/or thats what your budget allows, go for it.

Sat Nov 01, 2008 10:04 pm

Jacob, get the reducer that is designed to mix with your primer!

Mon Nov 03, 2008 2:15 pm

best suggestion...

anytime you buy products, always ask for the p-sheet (procedure page).

It will give you all the information needed to use the product. It will give you the mix ratios for mixing products, air pressure settings, cure times, flash times, which reducers you will need,etc.

These alone are worth their weight in gold for a new comer (or veteran for that matter) to the paint world.

Cant vouch for transstar products, but I agree with previous comments. You get what you pay for. PPG makes amazing products and they are what I prefer to use. They have all their product information available on their website. They make some lesser expensive lines like shopline that won't break your budget, but offer pretty decent quality compared to other entry level brands. They can save you a lot of money on things like primer and basecoat. That way you can afford to get a higher quality clear (from PPG) and preserve your paint job by getting better UV protection.

Some other tips for good measure. As mentioned start with about 35 lbs. of pressure from your gun. And anytime you adjust the air pressure you'll need to adjust the fan pattern accordingly. And equally as important as you'll find gun settings...watch your speed and how you're holding your gun. an average pace is about 1 foot/second. And your gun should always be perpendicular to your panel. and a safe distance at the suggested pace is about 8-10 inches away from your panel. This can be adjusted too as you get more compfortable, but it should work pretty well for beginning paint skills.

Good luck with all your painting endeavors. Keep us posted on how it all turns out.

Mon Nov 03, 2008 6:33 pm

pachood wrote: It likely means 10psi at the cap(although I have never seen it suggested at cap pressure). You will probably have 35-45psi entering the gun, 7-10 exiting.

Okay, I have seen this on the spec sheet for the paint I am using. I’m shooting with a Warwick LVLP gun with 25psi to the gun but how do you know/measure the PSI at the nozzle?

Mon Nov 03, 2008 8:10 pm

This is what we used:

http://www.sata.com/Produkte/produkt.jsp?index=34-a0-001-3-6704_test&menu=05,40

Does it help properly set up the gun? Yes. Is it necessary? Probably not.

Its really more about pattern, and proper atomization apposed to following the book especially when it comes to primer surfacer.

Wed Nov 05, 2008 3:33 pm

Just start with some taped up paper and mess with all the gun settings. Try with the fan all the way open, and the fluid adjustment all the way open. Then dial each one in just a little bit and see what it does for you. Get comfortable with your gun and try different distances away and see what happens. You can read all about different techniques, but it won't truly make sense until you know you're own gun, and see what not to do. Primer is the best for practice because its easy enough to fix if you run it, or if its too light.

Every gun is different. With different tip sizes, air pressures, etc.

Primer is meant to go on much heavier then basecoat. Not that it needs to be blasted, but it never hurts to be a little more generous if you're not sure you got solid coverage. But its important to keep it even. Youll see when you miss areas or go lighter when you come back to sand it. It'll burn right through.

Thu Nov 06, 2008 6:23 pm

Last time I painted a dune buggy right on the can it gives you the ratios needed to reduce the primer and paint.