I'm close to spraying my color. How much overlap do you recommend between passes? I want to make sure I don't end up with tiger stripes! Thanks for your continued help.

 

Gun? Paint brand and type? What pressure/tip/cap? Proposed reduction rate? Accelerator/hardener? Metallic or solid? Do you intend to clearcoat? How hot or cold will it be when you spray? All these variables play into how you shoot.

 

I'm using an HVLP gun, shooting Standox base coat in white. I'll use a 1.4 tip and cap, and generally have about 28-32 psi at the gun when I've used this tip to shoot the epoxy. The temps will be mid-60s, and humidity will be 40-50%. I'm not planning to use any accelerator. It'll be clearcoated with SPI Universal Clear. This is the first car I'm doing by myself, and the previous ones were nearly 20 years ago. With what I've said thus far, I've pretty much exhausted everything I know!

 

First let me say I have a lot less experience than Grandmaster or porchdog... may they spank me publicly if I'm wrong but here goes. Color will be "thinner" than primer so back pressure down a couple PSI, and liquid in a bit. Use about 40 percent overlap. Be aware that the spray pattern might "dry up" a bit as the paint level in the cup goes down... less paint = less weight. If you adjust liquid to compensate remember to take it back out when refilling the cup. Huge sliding runs await those who forget....

Get something to use as test panels if you have a bit of paint extra and try gun/height/speed settings until you get the best flow out. Write these settings down (turns from full closed) if you'll test one day and paint another. Don't be afraid to compensate for wet/dry application with gun speed/ height/ gun settings (probably in that order) if you get odd result as you spray. Pay attention to how a good pass feels and repeat about 150 times.... your job will turn out perfect I'm sure!

 

what kind of gun ? if it is just solid white just use white epoxy for sealer. you will not get stripping in solid colors unless you use the wrong base to shoot on.

 

partially. SO NO SPANKING HERE markids 77.

You should not have to adjust you gun during the paint job due to fluid level being less in theh cup. The fluid will come out regardless the same becasue of gravity and "trigger pull" setting of your gun. Problems may occur if you let your vent in the lid get plugged up and it will create a vacuum...causing your paint to not come out as required. I always check mine during gun fill ups.

The overlaps will depend on your setting of the gun...but I go for generally 50/50 overlaps....sometimes its 75/25...sometimes its 60/40. But who is counting...find out what works in test panels and test, test, test. Your spray pattern and fluid setting is what is PARAMOUNT...along with distance from the panel and travel speed...and thinner/reducer choice.

(edited response from another post that I gave this information)

YES, When the basecoat is applied...much like lacquer...a medium-wet coat....NOT A HEAVY COAT.....and NOT A DRY COAT...that may be rough looking. You want to see that it is shiny-wet...but not soaking wet. Use a test panel to gain confidence and see how the paint reacts to your paint gun setting and style. AND...when the basecoat has flashed off....it will be dull with an slight "eggshell" texture....possibly the base coat may have a slight sheen to it.

Not knowing if you know or not...so forgive me if I seem a bit...insensitive.

The **** on your gun that controls fliud is important. In this case...I would turn it all the way in...so you have NO trigger pull...then back it out 2 to 2-1/2 FULL TURNS. Now my guns are HVLP gravity feed guns with a 1.3 head on it. If you gun(s) are different...you may adjust accordingly. BUT whatever you do...I personally/professionally do not advise that you have a FULL trigger pull when applying your basecoat and clearcoat.

Remember that thinner coats flash faster than ONE HEAVY COAT. Thinner in the last statement DOES NOT reference to the thinner you use to thin the paint...but rather in reference to film thickness.

Also keep in mind...eventhough many other painters may do it a different way...which is fine. I am a believer that when I am shooting at a controlled air pressure...lets say 45psi. The controlled amount of paint coming out of my gun is being atomized by that air pressure. I would rather find that "sweet spot" in fluid volume that works best with the air pressure and correctly thinned paint, so I know that I am atomizing the paint correctly and allowing the finish to lay down as smooth as possible....which also depends greatly on your travel speed with the gun, distance from the panel and the THINNER/REDUCER you choose to use for your CURRENT temperature at the time of painting. So your fluid setting on your gun at the air pressure you are set at can either atomize the paint into a workable mist...or basically shoot droplets of paint....which droplets can cause ORANGEPEEL...due to being applied to heavy. So you can have either BB's or golf *****...if you wanted to think about it in a magnified state. I prefer BB's.

It is a total balancing act...so that is why I mentioned TEST FIRST. I have been doing it so long it is second nature now. The only part that I have to adjust is my grade of thinner/reducer...because the paint system that I use in conjunction with my HVLP paint guns...I use ONE GRADE SLOWER reducer/thinner than what the temperature at the time of painting NORMALLY calls for. This is so that my basecoat has time to "flow" before it TOTALLY flashes off....and I DO NOT GET DRY SPRAY...when I am going from one side of the car to the other.

SO when I am painting...I am NOT TRYING to shoot it SLICK and DRIPPING WET. I apply my paint so that it is ...like I wrote above...a medium-wet coat....that may have very little texture in it...but when it flashed off...it is very slick and smooth..with very little texture, if any at all...and I DO NOT HAVE OVERSPRAY collecting on the other panels when it is ready for the next coat. Which confirms that my choice of reducer/thinner, fluid setting, and techinque is "right on the money".

And how do I know this...you may wonder....because when I tack off before the final coat of base..just to help pick up any lint or minor specks that the tack rag will pick up.....my tack rag is CLEAN...and does not have any color on it at all....that is how I know. But needless to say..if I have specks that will not come up witha tack rag...BEFORE my final coat of base....I wet sand them out CAREFULLY...depending on the color and other issues...which would take me days to type out.

So...if you are goiing to basecoat/ clearcoat this car...remember that you are not trying to get excessive basecoat film thickness. The clearcoat is where that comes into "play" so you have good protection from the UV'S of the sun. Get enough color to achieve "full hiding".
"DUB"

 

It's the eastwood concours gun. So far, I'm pretty happy with the way it's been shooting with the epoxy and primer.

 

Many thanks, Dub. I find I'm still fine tuning the gun more than I expected I would have to. Today I shot my last primer coats, and they were the best I've done so far. I haven't been able to find that balance you describe between the fluid flow resulting in a coat that is wet enough, but not too wet. I wonder if I'm not running enough pressure at the gun? I'm not having problems with sags, but my impression is my coats are going on too thick - based on the quantity of material I'm using to get around the car. If you don't mind, I'll give you a call before I shoot again.

Ernie

 

Ernie-Hornetpilot
CAll me anytime. that works best for you.
"DUB" (704)394-5150 EST M-F 8:30-5:00
Beginning of the day or end of my day works best for me...But it really doesn't matter. whatever works with your schedule. If you get my answering machine...leave a name and number and I will call you back...just in case I am on the other line...because I do not switch lines and put people on hold.

 

Just a quick note... primer has much more "body" than reduced topcoats and unless you are reducing the surfacer to sealer viscosity you're unlikely to get a slick coat. Don't despair that your equipment or technique is lacking until you actually shoot some color!

 

TOTALLY.
The choice of hardener (if it is able to be adjusted for temperature) for your primer...along with the thinner/reducer choice for temperature conditions...can aid in getting the primer to lay out flatter ....and not be so full of texture. BUT...this once again deals with your "style" of spraying, gun settings, and air pressure. Its only primer surfacer...and it will sand down as designed. AS long as the texture is not heavily grainy or dry-sprayed...there should not be any problems...as long as you apply enough primer so block sanding can be achieved without "breaking through" to the fiberglass,SMC or body filler used.

When applying the first coat of any product ( primer or paint). You are ultimately trying to spray this coat with the least amount of "heavy texture". Because if you start off with texture...it is hard to get it out without changing something.. (i.e. adding more reducer/thinner, or changing techinque,etc) You do not want "gravel guard" texture if at all possible...it just makes it harder to get smooth...and you are sanding off a lot of your primer...that would have been used to give your primer sufficient build.

"DUB"

 

Many thanks everyone. I got the color sprayed today. I think it looks really good. I'll pull it out in the sun tomorrow to make sure I've got full coverage before I shoot the clear. All of the comments here were very useful. Thanks again.
Ernie

 

Ernie,
If you applied the basecoat...and IT does NOT have clear on it yet....BE CAREFUL while pulling it out into the sun to check for complete hiding. Unprotected basecoat getting oil from handling with bare hands can cause some problems if it is wiped down with a wax and grease remover. If you do it...pulling the car into good light...do it fast...and not allow outside contaminents to get on it. This is most important if you sprayed a metallic basecoat. Much care should be given to protect the final layer from any type of heavy disturbance....so metallic structure is not effected.
"DUB"