Eliminating Seams Between Colors

"Where were you when I laid the foundations of the earth?
Tell me, if you have understanding.
Who determined its measurements?
Surely you know!
Or who stretched the line upon it?
To what were its foundations fastened?
Or who laid its cornerstone,
When the morning stars sang together,
And all the sons of God shouted for joy?"

Job 38:4-7

Paint has thickness

Scott Chastain said:

Dear Listers: I would like to know specifically how the pros are able to eliminate the seams between colors and patterns; that is, after the clear coat is applied and buffed, running a hand over the painted surface reveals no noticable transition between the colors. Scott Chastain
RV-8 N898W Paint Merced, CA

Click to expand...

Scott no paint expert but when you put paint on top of another coat it builds thickness. Transitions or stripes, you'll have a ridge, as far as I know. The only solution or mitigation is make the paint layer on top as thin as possible. Some colors have greater build thickness than others. I recall red and yellow are thicker because they need more coats to build the color. So plan to put the thinner color on top. Some hot rod guys put their trim/stripes/flames on first, tape off and shoot the base coat on top, a reverse ridge if you will. It is suppose to be better, less noticeable but more work taping off.

I'm sure you will get a better answer (I hope).

One trick that does come to mind is pin striping on transition lines. The hot rod guys do than around their flames and trim, thin width, dark color. It fills in the ridge and than they clear over it all. Putting on more clear coats may help. More clear coats is a needed step if you plan on color sanding. Never did it but seen it done. It's extra work for sure. More clear is extra weight and chance for runs and sags. Frankly ridges are not that bad; you can feel them but visually not an issue.

The clear coat by the way is also made to not NEED sanding either. Color sanding is a technique to get higher shine, smoothness and deeper color.

Color sanding involves several sanding steps using super fine sand paper starting with at least 800 or finer and than going to 1500, 2000....4000 grit. Soapy water keeps the paper from clogging. It smooths minor imperfections, orange peal and any small minute particles or dust in the clear. After careful sanding (in many small steps up to 4000 grit) you buff the clear out. Some times you sand than add more clear coats, than sand again and than buff. If you do re-clear on a smooth surface, runs and sags are more likely. It's lots of work. When painters plan color sanding, they typically add several extra clear coats like 6 verses 3. That's extra weight by the way. More coats means runs and sags are more likely.

Sanding through the clear into the paint would be bad. Ironically if you see color on your sand paper, when color sanding, you went too far. To fix it would not be fun. You basically have to sand all the clear off that panel and repaint it and re-clear and......

You can sand the base coat, if there are imperfections to remove. Usually you have to repaint the panel again before clear coating. Check with the paint manufacture. I have heard of sanding the base as a matter of course, but most paint systems are made to shoot the base with no wet sanding before clear coating. If the base coats are rough, you may not have put enough reducer in.

Can you imagine Toyota or Honda having to wet sand the millions of cars they make? The key is to put clean, smooth, base and clear coats down, with out dirt, orange peal, runs and sags so sanding is not needed (easier said than done).

Personally I would not want to color sand a whole plane, with the uneven surfaces, rivets and so on. Its 4 or 5 sanding steps and buffing. Not all painters are gung-ho for this technique, but if done right, it can make the paint/clear noticeably smoother (for a perfectionist at a car show). Think about the work! It's an good technique to correct small amount of localized orange peal or remove dust particles, but the whole plane? Like I said, hope you get a better answer. I am going with JetGlo, single stage and no trim and no sanding!

ppg

when painting ppg base dbu or dbc if you attempt to sand the base colors which you should not, they will blend onto each other. the ppg base colors IIRC should be topcoated within 24 hrs. or more color needs to be applied.
if i were trying to eliminate this i would clear the plane sand the lines with 1200-1500 then either put one more coat of clear on or buff. and the buffing would depend on the remaining film thickness.. there are tools to determine that but i have never used one.


good luck

Grady at Glo Custom did what you are talking about on the stars on my cowl. It is as smooth as a babies rear end if you run your hand over it. It is more or less filled with clear coat and would probably add a lot of weight if you were to shoot your entire plane this way. What might be a better idea is to watch the videos that the EAA did a few years ago where they built an RV-8. When he got to the paint he showed how to pull the masking as soon as he painted an area so that the edges round over and take the harshness out of the transitions. They did some close ups and the technique seemed to work really good. Sorry, but I don't remember the name of the series I'm referring to.???
Obviously I'm no painter but have been around RV's long enough to know to "Keep it light" even if it takes somebody elses plane to make it happen.

Best,

Pulling tape

Bryan makes several good points. The tape-pulling trick worked better with the older single stage paints where you had some time before it dried. Also, be very aware of the weight of paint. I have seen several spectacular paint jobs recently that have to be very heavy. It is very easy to get tangled up in the car/motorcycle mentality of lots of layers and buffed clearcoat. Just remember that it can weigh a bunch.

John Clark
RV8 N18U "Sunshine"
(Two trim colors on white, shiny, but with minor "ridges")
KSBA

I'm in the process of painting my Midget Mustang. The graphics are painted. As others have said: Basically, the only way to make the edges disappear is with additional coats of clear.

My plane will be painted up similar to Danny King's. I can still feel the edges, but just barely. The painter applied MANY layers of clear and then I wet-sanded the fuslage from the lower longerons up to take out the high spots. The painter then buffed the fuselage. It's pretty nice.



Best regards,

Rod Woodard
Loveland, Colorado (KFNL)

Series

The series Bryan is refering to is "From the Ground Up". i was going to suggest the same thing, but got beat to the punch.

Hope all sprays well.

Another technique is to not paint any color over another color. I have 3 colors on my RV, yellow, black, and red. Each color butts up against the next color. Scuff the butt joint and spray clear. Its not glass smooth but its close. If I had done one more sand and clearcoat, it would have been very smooth. I just didn't have the energy left...

Karl

From the ground up tapes for sale

I have Volumes 2, 3 & 4 video tapes of "From the Ground Up" made by EAA Television and the Discovery Wings Channel for sale

I do not have volume 1.

The above mentioned painting method is on tape 4

These are original VHS tapes in the original boxes. They are not copies.

$ 40.00 for all three tapes plus $ 5.00 postage

email me at [email protected] or call me at the number below.

Mike Stephenson
Lubbock, TX
806-252-7100 (cell)

Yes

RV8N said:

Another technique is to not paint any color over another color. I have 3 colors on my RV, yellow, black, and red. Each color butts up against the next color. Scuff the butt joint and spray clear. Its not glass smooth but its close. If I had done one more sand and clearcoat, it would have been very smooth. I just didn't have the energy left...

Karl

Click to expand...

I did the same thing on a 427 Cobra kit. Butt the colors up to each other and it'll save you a lot of weight as well but it's a lot of extra work covering what is already painted painstakinly carefully so that there aren't voids between the colors.

Regards,
Pierre

Just as a point of reference, for the straight-line graphics--like the MM I letters on my plane, we just painted the bigger color (red in my case) first and then taped off the portion we didn't want black... I.e., leaving the red border.

As someone will surely point out, this means that where there's black on the letters on my plane there are MANY layers of paint. Not a big deal as far as I'm concerned.

Here's what the stencils looked like:



And then we painted the red:



and finally, the proper width fineline was applied:



At some point I'll have all this stuff up on my website, but who knows how long that'll take!

Hope this stuff helps,

Rod Woodard
Loveland, Colorado (KFNL)

Hi Scott:

Here are a few more photos of the process:

We painted the white on the stars and bars first. Everything else is taped off.



Here, I'm starting to remove all the mask. It's really cool to see things start to take shape as the tape comes off.



And the final product before the clear goes on:



As for the Norton brand masking sheet, the bodyshop I'm working with buys it through their normal paint supplier, Finishmaster. I Googled their website, but it doesn't show products, just contact information.

I did a quick Google search on "Norton masking products" and didn't find much. I found a product by Evercoat that seems similar. The stuff is just a VERY thin plastic. You're right, though, it would be nice to have a roll sitting around the shop just to keep stuff from getting dusty when I start sanding the inside of my cowling!

Here's a link to the Evercoat-brand plastic sheet.

Best regards,

Rod Woodard
Loveland, Colorado (KFNL)

paint all your base colors,then clear coat 3 to 5 heavy coats .(i use my finger to feel the tackyness between coats,not in the area seen,on the tape).let dry 24 hrs.then sand with 1000 to 1500 grit wet with a rubber pad,you can sand down the hump/valley between the color coats,it might take 10 to 15 coats of clear,but i have burried thick decals so you cannot feel them.also thin your first coats less than recomended and your final coats more than ,it will flow out better.

Weight??

g zero said:

paint all your base colors,then clear coat 3 to 5 heavy coats .(i use my finger to feel the tackyness between coats,not in the area seen,on the tape).let dry 24 hrs.then sand with 1000 to 1500 grit wet with a rubber pad,you can sand down the hump/valley between the color coats,it might take 10 to 15 coats of clear,but i have burried thick decals so you cannot feel them.also thin your first coats less than recomended and your final coats more than ,it will flow out better.

Click to expand...

Wow! It must look great, but what does it weigh? I put what amounts to 3 coats on my RV8 and it gained 30 pounds. 10 to 15 coats? Yikes.

John Clark
RV8 N18U "Sunshine"
KSBA

edge

I knew some guys that painted aircraft and what they did on the edges was take a double edge razor blade and curl it slightly with there thumb, index and middle fingers.

THey would run it along the edge of the strip to knock the edges down.

Never tried it but they had good luck doing it that way.

Scott Chastain said:

Dear Listers:

After etching/alodining/epoxy priming, I am currently in the process of base coat priming the control surfaces. I will be using a number of different colors with lots of masking and taping. I'll be using the Deltron 2000 base coat system with the Concept clear coat.

I would like to know specifically how the pros are able to eliminate the seams between colors and patterns; that is, after the clear coat is applied and buffed, running a hand over the painted surface reveals no noticable transition between the colors. Since the base coats are applied in relatively thin coats, it would seem dangerous to be color sanding these. I have yet to learn exactly what painters mean by the term "color sanding," since some use the term after the clear is applied, and others use the term before the clear is applied. Either way, any information here would be a big help. Thanks!

Scott Chastain
RV-8 N898W
Paint
Merced, CA

Click to expand...

Scott,
I experimented with a few techniques prior to painting the plane as I had no prior painting experience.
I ended up with the following: I sprayed clear heavier in the areas of color transitions. After the clear dried I sanded the transitions until they were completely smooth. The clear is then quite thin on the second color. Finally I sprayed clear again over the whole thing, sanded and buffed
The color transitions completely dissapear and I have had countless folks run their finger across them trying to figure out: How did he do that?
Chris