Q: painting direction/spray gun tilt

[fehdxl]

Couple questions for the group about a paint spraying technique.

First of all, I'm far far from being an expert. My painting experience is touch up here and there, some priming, and a motorcycle I painted with DuPont base/clear-coat a few years back.

So my questions have to do with the direction of spray. On the motor cycle, I noticed that when spraying the clear-coat, if I tilted the gun slightly so that the 'overspray' went toward the unpainted section of the part, that the clear-coat flowed out nicely. Conversely, when the 'overspray' went toward the already sprayed area, it left the surface with a light dusting (overspray?) that did not flow out to be smooth and therefore looked poor.

Tonight I painted a nose-gear door with PPG DCC and it didn't seem to matter as long as I went slow enough so there was enough paint to flow out.

So, has anyone experienced the same? Is this 'dusting' common? Is it a result of the type of paint? Temperature? Reducer? Or all of the above?

Thanks in advance for the insight!

-Jim
40603

[jrs14855]

Go over to Columbus and talk to Paul Meule(sp)??? Pay him some money for a consultation. When you are finished you will probably beg him to paint your airplane. Paul has had three consecutive Oshkosh Grand Champion Plans Built Airplanes. He is a true artist with a spray gun.

[fehdxl]

Jim,

Is that Columbus, NE?

Thanks,

the other Jim

[Andrew M]

The purpose of reducer is to slow the evaporation of the chemicals that are there to thin the paint just long enough for it to flow out. The cooler the temperature, the better. Also reducers are designed for temerature ranges. It is a balacing act, getting enough paint to flow out fast enough without putting so much that it drips. Position of lighting can help see how much is going on to by seeing the "glare or gloss" as it goes down. Working "downwind" helps with the overspray issue you brought up. Flash off (and flow out) time can be in the minutes as well. Keep fooling with it, you will figure it out.

[N130PM]

You are thinking about it too much. You don't need any tilt, by doing so you are spraying an uneven fan pattern. DCC is the most simple stuff you can shoot. You just need to convince yourself of it. Try this, get a shop light with about a 150 watt bulb. Move the light with your fan so yo are looking into it. You will be able to see the molecules flow. If you are moving too fast and laying it dry, it will show. Too much build from too slow a pass and it will show. Keep in mind. Those particles are going to reactive for a while. So what you have at the time you finish may be something much different the next day when you look at it. Dcc will flow just fine in the 4-2-1 ratio. I've seen the dry edge of a fan get nicely absorbed overnight. So what happens if you mess it up? Well you have just laid a very nice color base, thats all. Go back and wet sand with 1000 grit and shoot another coat and watch how nice it comes out. Don't be stressed about a do over, sometimes they truly come out the best. As far ast the gun. Don't get creative. Learn what works for you and do it that way every time.

Here's a good forum with tons of talent to search.

http://autobodystore.com/forum/index.php

[jrs14855]

Columbus NE he is in a large hangar behind the ramp

[fehdxl]

Thanks guys, I appreciate it. -Jim

[DaAV8R]

Force drying works wonders on DCC. Paint flows out great and cooks off completely in 30 or 45 minutes. For small parts I set them if front of the oven, or sometimes use a heat lamp for larger parts. Small imperfections will often flow out when heated.