Gluing Paper back on foamboard

Matthewdupreez

Legendary member
I'm doing shaped wings (master series style) on my new plane but still wanted under camber on the wing tips. So I thought I'd see which glue worked best. I pealed the paper off one side of the FB, shaped the FB and then reapplied the paper. For each glue I spread a thin layer on the foam, let it get tacky and reapplied the paper. After waiting a couple of hours I tried pealing the paper off.


View attachment 212845

Rubber Cement: Didn't peal up on it's own but came off easily
Wood Glue: Strongest bond but couldn't keep it from wrinkling when I put the paper back on
Super 77: After an hour it had fair adhesion, after 2 hours was better
Gorilla Clear: Good adhesion but the messiest of the group
Beacon (from Dollar Tree): Excellent adhesion after an hour, no wrinkles and not messy - The Winner

View attachment 212846
You could also try wheat glue... It's what I use to make my foamboard...
White flour:water 1:4.... Stir until smooth, then boil for ~2 min...
 
Another great idea. If it's worth doing it's worth over-doing! (see "Still Up a Tree")
My scale only reads to the nearest gram. I trimmed the larger samples to 3" x 6" and weighed them.

Raw foam board with paper on both sides - 3g
Rubber cement - 3g
Wood glue - 3 g
Super 77 - 3g
Mode Podge - 3 g
Beacon (2" x 5") - 2g
Gorilla clear (2" x 5") - 2g

My totally semi-scientific conclusion: @Piotrosko and @Monte.C are right. If your plane is significantly overweight then you must be "doing other odd stuff that is heavy too".
Haha- like building a hot glue mess!!!
 

SSgt Duramax

Junior Member
I think the glue weight test would best be administered on a similar sized part to build.

My thought was to do sections of Armin wing since they are easy to build, and do hot glue, white GG, and maybe wood glue. Then extrapolate the results to what maybe a 30" wing would be. 10 inch sections should do right?

On a side note I stopped by the dollar tree today at lunch and picked up some foam board I didn't really need (but it was really straight and nice with no waves and not warped), but I guess you can't have too much, and some posterboard I did need, and I also took the plunge on the two bottles of Beacon glue they had available, so I will report back.
 

Piotrsko

Master member
Another great idea. If it's worth doing it's worth over-doing! (see "Still Up a Tree")
My scale only reads to the nearest gram. I trimmed the larger samples to 3" x 6" and weighed them.

Raw foam board with paper on both sides - 3g
Rubber cement - 3g
Wood glue - 3 g
Super 77 - 3g
Mode Podge - 3 g
Beacon (2" x 5") - 2g
Gorilla clear (2" x 5") - 2g

My totally semi-scientific conclusion: @Piotrosko and @Monte.C are right. If your plane is significantly overweight then you must be "doing other odd stuff that is heavy too".
THAT'S a good start, but I suspect that an accurate test would be expen$ive and time consuming mostly to standardize all the variables. My beer scale accurate to .01gram says DTFB densities vary. Those densities may or may not affect the results
 

Mr NCT

Site Moderator
Final result: Paper on both sides of the foam board on a shaped wing. Sure hope the 108 square inches of excess glue doesn't put my 36", 31", 28" wing span triplane over weight!! :unsure::eek::ROFLMAO:

IMG_3447.JPG IMG_3448.JPG
 
I saw that and I think you're right, the world might end but that hinge will still be here! Also just watched the build video for the new MM Corsair and saw John gluing paper back on the underside of the wing tips. Guess I was plowing old ground.
I wasn't aware of that happening in a video. Cool that you found it. (Funny how that happens. More often than just random.)

I added the 2nd layer of paper because I don't trust any tape on this brown FB surface for any length of time. Painting the thing would help a little, but do I want to rely on a coat of paint to hold my rudder on? Now the weak spot is the tape-to-tape connection in the middle, but I gave that a drop of CA where it won't affect the hinge swing.

In places where weight isn't as much of an issue, it allows for a little more creativity. I'm kind of amazed at this hinge.