Printable Version of Topic

Posted by: worn Oct 11 2015, 04:44 PM

Hi to all, especially you experts with a spray gun. I know who some of you are, and you know whom the other are.

I have now painted a few cars and since I stick to single stage and can color sand, it has worked out pretty well. Especially the easy parts.

What I haven't figured out is how to deal with inside corners. I understand that physics is against me, in that a ball or beam of light hitting a ninety degree inside corner wil come straight back at the sender. On inside corners, I sometimes cannot get coverage unless I settle for granular balls of paint that settle in the region. Tightening the pattern by closing the side jets that make the brush pattern for the gun seems to help as does using the smallest gun possible. I suspect though that expert advice would be better than my muddling through. Winter is closing in fast, so you have till spring to answer. Still, realistically you will have forgotten long before that, so please help me now instead.
I am using bare metal, covered with DP50, followed by K36 sanded, followed by Deltron. It is Bahia red, so it looks pretty much like a major crime scene when the paint is flowing. Thanks folks!! You are amazing people.

Posted by: r_towle Oct 11 2015, 05:21 PM

Airbrush gun used prior to painting the field.

Posted by: rick 918-S Oct 11 2015, 06:01 PM

Narrow the pattern, dust it in, When you come back over the area with a full wet coat it is less likely to collect dry spray.

Posted by: worn Oct 11 2015, 07:02 PM

Thanks folks. With Ricks method I can keep the main gun hooked up? Dust as in farther away, or just less trigger? Does it help to try to do each flat at a time?

Posted by: rick 918-S Oct 11 2015, 10:30 PM

What area are you painting? A guy that paints a lot will develop an unconscious thought process. Hard to explain reflexes.

Posted by: mbseto Oct 12 2015, 07:23 AM

All inside corners are non-visible aren't they? Trunks, interior under the carpet, etc. Is it a stupid idea to brush those areas?

Posted by: worn Oct 12 2015, 07:43 AM

My big problems are in trunk and footwells, especially places where there are brackets and protruding pieces.

Also if you have some advice about the back of trunk lids that would be great. If I strip them to bare metal no matter how well I clean them, there is always dust that comes out from beneath the reinforcement web. I am thinking that the strategy might be minimal clean up and spray over what is already there instead?

Posted by: worn Oct 12 2015, 07:45 AM

Maybe I can get you to pantomime the techniques when I next come up to the North. Brrrr. Cold. Like here.

Posted by: worn Oct 13 2015, 10:35 AM

Bumping to keep up with the build threads. Any one else have painting advice?

Posted by: 7TPorsh Oct 13 2015, 11:09 AM

Is this for interior painting? First thing that came to my mind is how the H do you paint the underneath and inside of the targa bar?

Posted by: 76-914 Oct 13 2015, 04:00 PM

I had the back glass out when I painted mine. I used a small touch up gun. Because of the angle, be careful your gun doesn't drip when tilted.

Posted by: Andyrew Oct 13 2015, 04:16 PM

I paint the underside of the targa bar and the jambs the day before I paint the car
I paint the drivers side from the passangers side and vice versa. Turn the feed down a bit and narrow the spray pattern. It sprays a bit dry from so far but it typically turns out well. I spray about 2 feet away vs typical 18"

Posted by: Rob-O Oct 13 2015, 09:33 PM

Some guys don't like them, but to me using a pressure pot is the only way to go. The freedom to spin the gun upside down makes painting areas like underneath the targa bar easy and allows you to concentrate on laying down a nice consistent coat.

As for the corners, you're working against the air pressure. Ultimately you want the lowest pressure possible to get a good spray pattern for the amount of paint you're trying to get out of the gun at any given moment. Let's say your hand movement is slow, then you probably don't want the feed of paint to be high, because you'll glob the paint on in thick coats. So you should concentrate on finding the amount of feed that gives you the thickness of coat you desire. Then adjust the spray pattern pressure to get the spray pattern correct. Most newbie painters err on the side of too much overall gun pressure. They then have the issue you're having (called blowback). You notice it when doing corners, but a pro notices that he's just blowing a lot of paint out of the gun, and that costs tons of money. Because if it's blowing all over the booth instead of what you're painting, then yourr wasting the paint (called transfer efficiency, or in real terms...how much of that gallon of paint I just sprayed ended up on the car versus on the floor, me, the walls and out the exhaust of the booth?). Good paint is too expensive to waste by sending it through an exhaust filter and up a stack and out into the atmosphere! Good luck!!!!!

Posted by: worn Oct 15 2015, 11:44 AM

Yeah. At around $500 for a gallon mixed it seems important. Yes it is the interior, but I also have a hard time getting the inside of lids painted because no matter how hard I try there is always some dust under the reinforcement web. Especially after I strip the paint off either by sanding or aircraft stripper. I know, more than one problem. The airflow tip is a great one.

So in some cases is an HVLP working against me? I thought they had higher transfer rates, but they also shoot a lot of air. Or maybe I try turning down the pressure. Thanks!