Author Topic: Lemon Yellow base coat (Read 1707 times)

Dan Bregar · « **on:** December 19, 2011, 04:53:55 PM »

Hi guys. Last Spring I tried to paint Randolph Lemon Yellow directly over a clear doped Silk-Span wing. It took 32 coats of brushed on yellow to cover. Just kidding on the 32 coats part as I gave up after 6 coats. And it dawned on me that I probably should have applied a primer or base coat that would help the yellow cover much better than it did. So my question is, for this color of bright yellow what kind of base coat and what color should it be to help the yellow cover in 2-3 coats ?

Avaiojet · « **Reply #1 on:** December 19, 2011, 05:05:33 PM »

Quote from: Dan Bregar on December 19, 2011, 04:53:55 PM

Hi guys. Last Spring I tried to paint Randolph Lemon Yellow directly over a clear doped Silk-Span wing. It took 32 coats of brushed on yellow to cover. Just kidding on the 32 coats part as I gave up after 6 coats. And it dawned on me that I probably should have applied a primer or base coat that would help the yellow cover much better than it did. So my question is, for this color of bright yellow what kind of base coat and what color should it be to help the yellow cover in 2-3 coats ?

Dan,

I would have used white as a base coat then apply the yellow of your choice.

CB

Bill Little · « **Reply #2 on:** December 19, 2011, 05:15:03 PM »

Hi Dan,

When everything is said and done in the preparation and you are ready to go with the yellow, spray a light coat of Duplicolor sandable WHITE primer. give it a light sanding with 600-800 wet, then put on the yellow. DON'T USE SILVER as a blocking coat for yellow unless you want slime chartreuse..............

BIG Bear
AMM

Dan Bregar · « **Reply #3 on:** December 19, 2011, 06:44:26 PM »

Thanks guys, I thought white might be the best, but wasn't sure. I've really been partial to bright yellow since my combat days, as it has good visibility for me under most sky conditions. So since I have a full quart of it I will be using it again on my next airplane. But this time I'll take you guys advice and use a white primer base. You guys have a lot of experience painting toy airplanes for sure. Thanks

larry borden · « **Reply #4 on:** December 20, 2011, 07:06:16 AM »

I'm partial to yellow also. I put down a base coat of white and then apply the yellow. Learned this trick after having the same problem on a Sterling P-51 that I painted black and yellow.

Randy Powell · « **Reply #5 on:** December 20, 2011, 10:58:26 AM »

Depends on the effect you want. I shot chrome yellow over gold. That looked very good. For lemon yellow, I'd probably go with white as has been suggested. There are other options depending on what you are looking for.

Tim Wescott · « **Reply #6 on:** December 20, 2011, 11:31:36 AM »

Note that this all applies to red, too -- red and yellow are both very transparent colors, and "want" to go over white.

(Unless you're trying for a candy color or other special effects, in which case I don't know what to recommend. Other, of course, than doing whatever Randy or Mark Scarborough says to do).

Don Hutchinson AMA5402 · « **Reply #7 on:** December 20, 2011, 01:19:49 PM »

From the Randolph products Procedures Manual: "If you select light or brilliant topcoat colors, application of one or two coats of white as a base coat is recommended."
From a Classic Aero book. "Yellow, orange and red butyrates will appear much more brilliant if you spray two coats of white butyrate on the surface first."
Classic Aero was really good dope, too bad it is no longer being made.
The gospel according to those who know!

Dan Bregar · « **Reply #8 on:** December 20, 2011, 04:08:00 PM »

Quote from: Randy Powell on December 20, 2011, 10:58:26 AM

Depends on the effect you want. I shot chrome yellow over gold. That looked very good. For lemon yellow, I'd probably go with white as has been suggested. There are other options depending on what you are looking for.

Randy

"Other options" Please elaborate if you would.

Dan

Dan Bregar · « **Reply #9 on:** December 20, 2011, 05:07:37 PM »

Don

You are one of those guys that reads directions. And if I would have read them, I would have avoided some pain. Thanks for pointing that out to me. I was in too big a hurry. "Haste makes waste".

Randy Powell · « **Reply #10 on:** December 20, 2011, 09:13:11 PM »

Dan,

I've shot yellow and red over a bunch of different base coats. I shot a basecoat yellow (car polyurethane) over black pearl once. Very intense look. I shot school bus yellow dope (chrome yellow) over Cadillac gold metallic. Gave sort of a creamy yellow finish. Usually if you want brilliant yellow sort of color, shoot it over white. You can tone the white down to regulate how intense the yellow is. Same for red. I've shot Pagan Yellow Gold (car color - sort of a really transparent yellow/orange) over bright red (that was shot over white) and got a sort of brilliant gold color.

House of Kolor has a bunch of charts showing what you get when you shoot one color over another. Really cool if you are looking at shooting candy colors over other colors.

Dan Bregar · « **Reply #11 on:** December 21, 2011, 04:09:28 AM »

Randy

How do you "tone the white down".

Dan

Bill Little · « **Reply #12 on:** December 21, 2011, 10:36:26 AM »

Quote from: Dan Bregar on December 21, 2011, 04:09:28 AM

Randy

How do you "tone the white down".

Dan

Add a drop or two of black to make it off white.

Big Bear
AMM

Tim Wescott · « **Reply #13 on:** December 21, 2011, 11:16:39 AM »

Quote from: Bill Little on December 21, 2011, 10:36:26 AM

Add a drop or two of black to make it off white.

Or get a good comprehensive color chip collection, and go through all the varieties of "white".

Bill Little · « **Reply #14 on:** December 21, 2011, 11:44:25 AM »

Quote from: Tim Wescott on December 21, 2011, 11:16:39 AM

Or get a good comprehensive color chip collection, and go through all the varieties of "white".

More ridiculous to me is the massive amount of the shades of black. There are plenty.

Randy Powell · « **Reply #15 on:** December 21, 2011, 12:44:45 PM »

Yea, you can either pic out a white color chip (and there are hundreds of different whites) or just start putting in other colors a drop at a time. Blue into pure white will usually increase the brilliance, red or black will tone it down.

There is only one "black", but there are hundreds of "off blacks". Usually some form of gray, charcoal or similar.

billbyles · « **Reply #16 on:** December 21, 2011, 04:04:40 PM »

Quote from: Randy Powell on December 21, 2011, 12:44:45 PM

Yea, you can either pic out a white color chip (and there are hundreds of different whites) or just start putting in other colors a drop at a time. Blue into pure white will usually increase the brilliance, red or black will tone it down.

There is only one "black", but there are hundreds of "off blacks". Usually some form of gray, charcoal or similar.

Hi Randy,

With my Sikkens polyurethane mixing system three blacks are supplied: 1. Jet Black (pure black) 2. Black to the blue 3. Black to the yellow. Looking at them in the can you can't tell the difference, but sprayed out you can. If you mix a formula color using the wrong black the color will not be correct at all. Before I bought the Sikkens system & went to their color matching class I thought "black is just black"...well, as you stated above it does make a difference.

Tim Wescott · « **Reply #17 on:** December 21, 2011, 04:30:16 PM »

Quote from: billbyles on December 21, 2011, 04:04:40 PM

Before I bought the Sikkens system & went to their color matching class I thought "black is just black"...well, as you stated above it does make a difference.

Worse than that, some colors are just not achievable with current pigments. I remember reading an article in a science magazine a few years ago "Scientists create a whiter white". Say what??? It turns out that pure neutral white pigments don't reflect all the light that hits them -- this article was about pushing the reflected light up to 99%, or 99.5%, or some other "not quite 100%" figure.

They announce "really black blacks", too. And I'm sure that the same applies for blue, red, yellow, etc., etc., etc.

Dan Bregar · « **Reply #18 on:** December 21, 2011, 05:49:36 PM »

Holy Mackerel Andy !!! Amazing that I've been building toy airplanes for over 50 years and don't know all this information you guys are posting. I thought white was white and black was black. I gotta keep things simple though.

Randy Powell · « **Reply #19 on:** December 22, 2011, 02:31:53 PM »

Bill,

Yea, most car paint manufacturers have some form of "pure black". Just black. The a variety of not quite blacks. As you say, you have to use the right one but that is mostly for mixing other colors. Just as most of them have what they term "pure white" or something like that then a million different not quite whites. I was looking at an Omni color mixing chart and they list 2724 different colors not counting special non-standard mixes. Of those, something like 600 of them are either some form of white or black. Fun stuff.

I will be driving home and see some car and take note of the model, probably year and apparent color. Then I go to autocolorlibrary.com and see if I can look up the color number. Then I call my guy at the local paint shop and ask if they can mix the color without binder and if any of the ingredients use elements with a urethane carrier. If the answer is yes and no, the I drop by the shop and have a pint mixed up. Probably why I have 40 paint colors under my bench.

Bill Little · « **Reply #20 on:** December 22, 2011, 03:20:49 PM »

I know y'all realize the various "shades" of color. I remember being at Ronnie Silver's shop (NASCAR and BUSCH) plus he does "customer cars". The painter grabbed a can of "Black" (PPG IIRC) and started shooting a 1/4 panel. Looked absolutely fabulous, but didn't match the "black" on the car (and it wasn't a "Blending problem")...... best to stick with the same brand as Mark and Randy say! LOL!!

BIG Bear
AMM

Avaiojet · « **Reply #21 on:** December 22, 2011, 03:27:29 PM »

Quote from: Ty Marcucci on December 19, 2011, 09:47:59 PM

What Bill Little says about NOT using silver as a base, is pure gospel. I did it once and ever see an egg yoke from an over cooked hard boiled egg. Yep, that color green/yellow or more like zinc chromate. I guess it depends on the hen that laid the egg. But such an UGLY color. Made me quit using both silver and yellow.

Silver can be added to white. If done correctly, it will cover easier with less coats. From two feet, can't tell the difference.

CB

John Leidle · « **Reply #22 on:** December 23, 2011, 11:11:06 PM »

Hey Randy,,, how bout Metalic Black?
John

Tim Wescott · « **Reply #23 on:** December 23, 2011, 11:30:42 PM »

I've seen car colors that do that. Presumably it's metal in a base that's translucent gray.

You could probably also do a "candy black", with a translucent gray over metallic.

I remember seeing a street rod that was translucent red over jet black -- the effect was very striking, it was a black car with red highlights that danced around depending on the angle that you looked at it.

Mark Scarborough · « **Reply #24 on:** December 24, 2011, 11:57:25 AM »

While black is the most opaque color of the bunch, it is to a degree translucent. I have sprayed out a car black, then do a let down with blending clear 50/50, and add pearls to it. In bright light, or directional lights like streetlights, or inside a showroom, it has miles of depth. You can continue to do let downs until you are virtually spraying a black candy with pearl. You can see about 12 miles into this, its really awesome.
Black used to be black, but with the different paint process, and manufactures going for "just the right look" you now have lots of blacks. IMHO the most difficult color to match is white. It takes literally one drop of a color into a quart to shift it one direction or another. Though I have not had to match the new Off blacks yet so they could be as bad.
Anymore when you go to repair a car, you get the paint formula, and look it up. then you get out your varience chip book and compare it to the car. some colors, maroons and golds particularly, may have 6 or 8 different variences for the same exact color. Its really a freakin nightmare..

Randy Powell · « **Reply #25 on:** December 24, 2011, 01:47:56 PM »

Mark,

I agree completely. It's basically get the number and hope the components work. Nice thing about painting planes as you don't usually have to match anything, just find what you want.

L0U CRANE · « **Reply #26 on:** January 04, 2012, 11:18:46 AM »

Life was much simpler some time ago...

The CG Shoestring profile had the formula for mixing the recommended ?green/?chartreuse? as simply so-much AeroGloss Cub Yellow in so-much (?) Green*

* - I don't remember which of the 'stock' A-G greens it was...

Also, among errors made, I tried a Candy Apple finish with A-G Metallic Red over a silver base. Nope! Looked like someone's stomach's response to that rotten, overboiled egg yolk mentioned above.

"Warm" colors go over "warm" base coats (red, orange, yellow of whatever formula) if you're trying for a healthy-looking "metallic." "Cold" over "cold" too. Blue, green etc.

For a transparent-type finish the base shouldn't be a full, pure color, as also mentioned above, just off white (to keep the brilliance of the upper color) in the directionof that color's "temperature" range.

Just some simple, crude basic ideas that should still be of value to keep in mind as you delve into the huge tomes of color chips and formulas...

Geoff Goodworth · « **Reply #27 on:** January 04, 2012, 04:45:17 PM »

Lou, the green mentioned on the Goldberg Shoestring building instructions is Cessna Green. The original colour was The 1949 Cadillac Chartreuse, (Colour Code 21 for the convertible only) nad it is nothing like the apple green that the airplane now carries in the Planes of Fame Museum which I believe is Sherwin Williams Chartreuse.

jim ivey · « **Reply #28 on:** January 08, 2012, 03:48:31 PM »

I like pink and black, or chartruse and heliotrope, strictly 50s stuff

Author Topic: Lemon Yellow base coat (Read 1707 times)

larry borden

John Leidle