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prkaye

Well Known Member
Well, after much deliberation and research, and after trying out a couple of rattle-can products, I've decided to paint my interior the way a real painter would do it - with a 2-part paint (the hardener comes in a seperate container) and an HVLP gun. I got a quite inexpensive gun, and the paint is a PPG paint. I'm going with flat grey because it'll be easier to play fighter-pilot ;).
My first problem in trying to find a rattle-can product was that most of these seemed to have a glossy finish, and I want a real flat finish inside the cockpit. The guys at a local paint shop (really helpful guys) also said that rattle-can paint would not be nearly as durable. So they talked me into the PPG paint which apparently is the same stuff that is used on firetrucks.
So, I'll be doing this soon. I'm going to be shooting the paint on top of a self-etching primer (rattle-can) that I've been using (the paint guys said this would work fine). Some of my parts have were primed before installation though, so I'm wondering what's the best way to clean these up before I apply paint? For some I want to very lightly scotchbright them to get a smoother surface (the primer is rough to the touch on some parts). Should I use water, or soapy water, or just a dry cloth to clean the previously primed parts before shooting paint?
Any other tips for a first-time painter?
 
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thinner

I've had the same tasks you describe- - after scotch-briting (new word), I run a laquer thinner dampened cloth over the area. just enough to clean up the dust, etc. then shoot.
 
If your painting removable parts I would sand with 400 or 600 wet or dry on the rough textured items. I like to use a small amount of soap when I wet sand. It will float the sludge off a little better. If they are fixed scotch-brite with grey or sandpaper. Be very careful prepping with lac. thinner. It will "melt" most rattle can anything. I use Dupont 3909 for all my pre-paint work. (I do it professionally for the last 25 years). PPG makes a prep-solvent also for their products. I believe that some people on this forum has used rubbing alcohol also but not sure how it works as a oil and contaminate remover. Hope this helps and good luck!
 
I can also give you some great tips on how to set up your spraygun if you need them.
 
Rough up with scotch bright as you described and then use a good Degreaser/Wax Remover, like PrepAll, or PPG equivalent. It is much less agressive than other solvents and is designed specifically for the purpose. Run a tack cloth over it after if you want to get rid of the occasional dust or fabric spec from your rag.

For best adhesion, rough up and then reprime before top coating. ( I did not do this but still had decent results.)

I do not believe PPG two part products are available in a "flat" finish. They make a flattening agent you add to the paint and a clear top coat that also flattens. The flattening agent takes some experimentation. It will make the paint more pourous, less durable, and a bit harder to clean.

There are some paint experts that cruise these posts, of which I am not, but I had good results with above.
 
I do not believe PPG two part products are available in a "flat" finish
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Hmmm... what they sold me they claimed is flat. When I get home I'll look at the exact name of hte product and post it.
 
As JonJay stated, PPG and most other suppliers do not have a dedicated paint that is "ready-to-apply" for a flat finish that I am aware of. My suppliers have an additive that you mix with the product to get your level of "sheen". Only bad thing about that is trying to do a repair down the road it is hard to match the level of flatness. As far as the gun setup, here is what my friend, and owner, of a reputable a/m paint manufacturer recommendations on gun setup is. And it works flawlessly. His name is Barry and if you call him, tell him Terry in Ackerman, MS sent you. His web address is SouthernPolyurethanes.com. You can go on his site and find what you are looking for.
 
Actually, i think I remember him saying something about a "flattener". He must have mixed that in when he mixed the colour. I'm going to test-shoot a scrap piece of aluminum tonight to see how it looks.
 
Another thing to remember when using a flattener is that the hardener will bring back some gloss. So you have to start out flatter than you want.
 
First Kleen

I use First Kleen on all my primed parts immeadiatly before shooting color. Dampen a rag & wipe, then again with a dry clean cloth. It's ready to tack & shoot.
 
orange peel?

OK, so I tried out the gun tonight. The gun had no directions, excpet on how to take it apart, and to shoot from 6-10cm away.

1) There is one knob on the gun. I assume this is for controlling how much paint comes through... if i turn the knob clockwise (right) should this increase or decrease the paint flow?

2) The results of my test were a finish that has a very rough, sort of pebbly appearance/texture. I guess this is what they call "orange-peel". What is likely the cause of this? Crappy gun? Too much or too little air?

3) When I spray a coat, how thick should i lay it on? Should it be so i see solid paint with no unpainted surface showing through, or so a much thinner coat?

4) how long between coats?
 
Orange Peel

The link below provides some insight on what variables can cause it. I had similar issues when I first started priming the skins inside the tail, it's much better now. Take notes on the environmental conditions, pressure, nozzle and positions of the controls and your finish. It's real important to get the light right so you can see when it just turns wet, if it's too wet you will get runs or orange peel. The environmental conditions affect the evaporation rate. Just my observations from being a newbie to painting.

http://www.sherwin-automotive.com/reference/troubleshooting_guide/orange_peel/index.cfm
 
If after everything it's still not flat enough, rattle can clear flat should make it uniform. Later touch-up is a breeze!
 
If after everything it's still not flat enough, rattle can clear flat should make it uniform.
Click to expand...

This raises a question. I'm matching my paint colour to the primer colour, because I really like the colour of my primer. I also like hte flat finish of the primer. The only reason I'm doing paint is for durability... the primer has very poor durability.
What about putting the rattle-can clear flat directly over the primer? Would this give me the desired durability?
 
Generally most spray guns have two "knobs" for adjustment, three if you count the air pressure. Not sure which knob you have on your gun. What brand is it? Just a guess it is the fluid knob. The best way to tell if you turn it all the way in and pull the trigger and then start turning it counter-clockwise the trigger should move back. Do this with the gun empty. That controls your amount of fluid thru the tip. The further out the more fluid. The other knob, generally on most spray guns, is the fan adjustment. It controls the width of the spray pattern, in makes it narrow, out makes it wider. The last is the air regulator. It naturally controls the air to the unit itself. On my SATA spray gun, which is a hvlp gun, indicates about 29-34 psi when it sprays my single stage paint correctly. You can get adequate results with a cheaper gun it just takes more setup time. My guess is that you may need to increase your air pressure some if it is low or reduce you paint to a thinner mix.
 
ahhh... yes there is a knob at hte back but I thought that was just to unscrew to take out the pin. It does move the pin back and forth in the nozzle, so I would guess this controls how much fluid comes through the tip. The knob on the side must be the fan control.
 
Follow the gun setup that I referred you to and it will address the variables. Oh and by the way, I looked at your website and the paint scheme will be awesome. I may have to take some of your ideas.
 
Thanks Terry! Right now I'm just painting interior... still have yet to decide wither to paint the exterior myself or have it done. I'm quite excited about the Golden Centennaires paint scheme. I actually got in contact with the chap who designed that paint scheme, and one of the team's pilot's who is building an RV-7 in British Columbia.
Another local builder is planning to do his RV-8 like the Golden Hawks, and we have another local RV-8 painted like the Snowbirds. Great representation of Canadian military airshow teams!

Question - is it bad practice to shoot gunwash through the gun, under pressure, during cleaning??
 
Pour as much paint out of the gun and rinse with a small amount of thinner, then pour clean in and spray thinner thru the gun. It is standard practice. With 2 part paint it is very important to keep gun clean. I always leave a small amount of thinner in the gun while it is in "storage". Also keep rinsing until the thinner is clean that is in the gun.
 
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