Foam covering

[jamal55]

I thought there would be another thread covering the topic but I couldn't find anything :/

Is it a good Idea to cover foamies (or at least some parts of them) with something other than tape (e.g. fiberglass) to make it more durable?
I was thinking that if you dont go too big you should be able to make it up for the extra weight with a bigger motor while making the model much stronger (and waterproof).

If people do actually cover their foamies what do they use? fiberglass, carbon, other?

Thanks

 

[Craftydan]

The average builders here don't bother with it . . . but who says you have to be average

Typically the paper is the weak link in these builds, durability wise. It adds a lot of strength, but even waterproofed foam (either by minwax or FT's WPFB) will delaminate with hangar rash and rough landings. If you want to go to a harder covering, the paper is the first thing to go.

As for what to replace it with, Glass is an obvious choice, which you'd apply using either resin for "hard and heavy" or polyacrylic for "light and refined". For these kinds of builds, Carbon tow or Kevlar strips become good reinforcements, but generally Kevlar or carbon fabric for the whole covering is overkill. cool, but overkill.

Here's a few builds/ threads that make use of it. There's more out there, but these are the first few I could pull off the stack of threads that look into this:

http://forum.flitetest.com/showthread.php?29203-Flite-Fest-2017-Bugatti-100P
http://forum.flitetest.com/showthread.php?23310-Bloody-Ripper-a-modified-Bloody-Wonder-for-composite-construction
http://forum.flitetest.com/showthread.php?29715-Flite-Fest-2017-Folkerts-Sk-4-no-compromises!
http://forum.flitetest.com/showthread.php?23228-Fiberglass-Foam-A-Tutorial-and-Discussion

 

[jamal55]

thanks for that one @Craftydan. Looks like the fiberglass makes a really good finish

 

[Hai-Lee]

My first line of covering especially on planes that still fly quite well but have the old lawn induced wrinkles in abundance is a little expensive but quite effective and strong.

I have a local supply of 1mm Balsa which after removing the paper from the foam, (as best as is possible),I use to plank the outer surface of the model. When finished and after a light sand I can finish the plane in a standard iron plastic film.

Whilst the weight does increase the strength goes through the roof and all of the off the shelf finishing decals and the like used on Basla models are suddenly easy to use on the model.

Just my 2 cents worth!

 

[jamal55]

sounds like loads of work and like it's gonna add loads of weight. You got any pictures of the final result?

 

[marc60]

Hi Jamal.
I use polypron for my builds. It's like depron. To reinforce I used two methods.
1/ Packing tape Like in this franckenstorch: http://forum.flitetest.com/showthread.php?19976-The-frankenstorch-plane.
I got the impression that the clear tape sticks better than the colored ones.
2/ Glass with polyacryllic paint (2 to 3 layers). like here in a P51: http://forum.flitetest.com/showthread.php?14781-Scratchbuild-polypron-P51-Mustang

Before glassing first time I did some tests to see what's the best way to degrease the foam and to see if there's a difference in sanding before or after degreasing: You can read it in the FT spitfire forum here: http://forum.flitetest.com/showthread.php?4288-FT-Spitfire-Build/page34

Advantage of glassing; Lighter than tape. You can use all available colours. Disadvantage; More work, more time drying in beteen layers of paint. More expensive.
Advantage of tape; quick, cheap, very strong. Disadvantage; slightly heavier than glassing. And it just doesn't have the looks of a beautifully painted plane

Greetz Marc

 

[jamal55]

Jesus mark.. went through you P51 build thread. You put so much work into that one! Even felt bad about the crash on the 3rd run
Yeah glassing seems more neat option. I can see that it sells for around £15 the half pint which is pretty expensive but it certainly looks a lot better and still way cheaper than fiberglass

 

[philgabanski]

I use the Hobby king wing tape. M ain readon being that a couple of layers heat treated will shrink tight around the foam.



I use a cheap heat gun to smooth the tape!