Foam Board Paint Test

lazermule

Member
I'm building an Old Fogey with my son and we decided to make the color scheme resemble that of a yellow Piper Cub so I went to Menard's and picked out a kitchen and bath interior enamel ($9/qt) to test out on some DTFB. I slapped a coat (brushed) on one side of a test piece of foam board and the ends and let it dry. When that coat dried, it looked good but had a slight warp toward the side that was painted. I then slapped a coat on the other side and let it dry and the warp was gone. The paint did not appear to have any ill effects on the foam board. Here are some pictures of the paint and it on the test piece:

The paint:
paint.jpg

Applied:
coat.jpg

Edge view showing no warp:
no warp.jpg

Hope this helps others that are looking for paint options on the foam board planes. Probably not the best finish with a brush, but with a light coat or two I think it'll look pretty good in the air.

LM
 
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If you apply oil-based Minwax polyurethane first, it significantly increases your paint options, and you don't have to worry about warping.

http://flitetest.com/articles/minwax-on-your-plane

http://forum.flitetest.com/showthread.php?4556-Painting-Foam-Board&highlight=minwax

I was a little skeptical about the minwax but couldn't be happier on the turnout. Got a tip to do a very fine light sand after the minwax has cured (before you paint) and the finish is even better. I had been using an airbrush for the smaller sections, but I was able to rattle can my Mustang with some rustoleum metallic finish paint and it came out great!

-Jes

P6030007.JPG
 

Jaxx

Posted a thousand or more times
Jes,

I second that. It really did come out great! I just Minwaxed my Mustang and one of my Spitfires today. I have another Spitfire, Bloody Wonder and FT-22 to Minwax tonight or tomorrow. I used a 2 inch foam brush, and it worked really well. I buy the cheap set from Harbor Freight. I love how rigid the Minwax makes the paper on the foam

http://www.harborfreight.com/10-piece-foam-brush-kit-95031.html
 

Foam Addict

Squirrel member
I was a little skeptical about the minwax but couldn't be happier on the turnout. Got a tip to do a very fine light sand after the minwax has cured (before you paint) and the finish is even better. I had been using an airbrush for the smaller sections, but I was able to rattle can my Mustang with some rustoleum metallic finish paint and it came out great!

-Jes

View attachment 25032

How strong is the plane compared to pre paint and minwax?

My Cessna 180 lost its empennage in mid air after I painted it,(with the exact same paint) as the paint weakened the paper's bond with the foam so I'd like to compare them.:D
 

Jaxx

Posted a thousand or more times
How strong is the plane compared to pre paint and minwax?

My Cessna 180 lost its empennage in mid air after I painted it,(with the exact same paint) as the paint weakened the paper's bond with the foam so I'd like to compare them.:D

Did you Minwax the Cessna before applying paint?
 

Jaxx

Posted a thousand or more times
No, but the foam was undamaged, it just felt...brittle.
I'm in the process of finishing up my Mustang. Now that the Minwax has cured, the airplane feels much stronger. It creates a nice outer shell that hardens the paper, and stiffens up the entire airframe. I would like to maiden this week/weekend, but can't decide which motor to use on this build. Decisions decisions :confused:.
 
Jes,

I second that. It really did come out great! I just Minwaxed my Mustang and one of my Spitfires today. I have another Spitfire, Bloody Wonder and FT-22 to Minwax tonight or tomorrow. I used a 2 inch foam brush, and it worked really well. I buy the cheap set from Harbor Freight. I love how rigid the Minwax makes the paper on the foam

http://www.harborfreight.com/10-piece-foam-brush-kit-95031.html

@Jaxx - Thanks! it's the nicest one I've made I'm actually afraid to do tricks with it as I am still too attached to turn it in to a pile of foam just yet, I'll be picking up those foam brushes in the morning! thanks for the tip! I wasn't looking forward to repeating the paper towel experiment. FYI I'm using a 2220 Exceed RC 1380kv motor with an 8x6 prop on my mustang. It flies pretty good but I can see myself wanting more speed once I get a better feel for it. I think an NTM 28-26 1350kv might do just as well and IMO better quality than the exceed motor, I'm flying an NTM 1200kv on my spitfire, and having fun. Also I've used a turnigy 2826 1400kv, it does pretty well with an 8x4 prop. I think my motors do all right on the FT 4ch planes but I think they are also on the low end of "the beef" range of things. I've only just begun to research my next step up and I've been looking at the emax 2215 motor (what I hoped my 2220 would match) and the NTM 3530 1400kv motor, if that doesn't get me full vertical I must be doing it wrong.

@Bladerunner - I'm a little too gutless to fly as far as they say my radio will go, I pretty much keep in line of sight where I can still tell orientation, I haven't noticed any signal issues (nor did I even think about that being a problem) If anything changes I'll post an update.

@ Foam Addict - I think the plane is definitely stronger since minwaxing it. I lightly airbrushed my spitfire with some color and it's starting to look pretty ratty, though it has many more flights, and some less than desirable 'landings' on it than the mustang there are several places on the spit where the paper is peeling. The minwax did create a sort of "shell" or at the least hardened the surface some, I did it mostly to improve the quality of paint and prevent the waving of the paper that I had with the spitfire. I can also say it added some weight I had to make a reasonable adjustment to my battery position after painting, this however was a positive thing cause now I can use my 2200mah batteries where as before i limited to 1500mah due to the heavy motor and awkward CG. I have an SU-37 I built from frcfoamies (thanks FT for the skills to do so) it looks sweet!! I wanna paint it up after I add the ailerons to it. I'll be minwaxing that for sure, it made it so much easier to paint, BTW I read on a post that if you give a light high grit (2000 was suggested) sand after the mix wax cures it makes for a smoother finish, I haven't tried this but I will on my next one.

-Jes
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
OS,

I picked up an Emax 2215 at Nall after my Turnigy motor's X-mount tore off the motor(!). Swinging an 11x6, it's a HAPPY motor on my P-51 and Spitfire. The P-51 (wiht LG) Cruises just fine at 1/2 throttle and settles to a nice greased landing at about 1/3-1/4. climbs out happy at 3/4. Been very pleased with fit and finish, and the power is plenty for the task.
 

SP0NZ

FT CAD Gremlin
Staff member
Admin
Moderator
Mentor
Crafty Dan, do you have unlimited vertical with the Emax 2215 on the FT Mustang?
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
With the landing gear on, I do not. Great big airbreaks, they are :(

Haven't tried it with the LG off, but my spitfire can accelerate in a near vertical climb
 

gailenjensen

Junior Member
Poly Plane

From personal experience, Don't use the aerosol polyurethane. I tested it on some scrap pieces first and I'm glad I did. Whatever they use for the propellant, it peels the paper off. I used regular poly in a regular spray gun with no problems. Then the Krylon H2O rattle can would come out with globs with the spray. It did smooth out ok.

If you apply oil-based Minwax polyurethane first, it significantly increases your paint options, and you don't have to worry about warping.

http://flitetest.com/articles/minwax-on-your-plane

http://forum.flitetest.com/showthread.php?4556-Painting-Foam-Board&highlight=minwax