A speedy way to scratch build a wing

[stevegallacci]

I'm doing a 1/48 Hu211 right now as an evil experiment. I made a rough airfoil shape out of drafting film and put some bamboo squewers and casting resin in it, and a few minutes later, had a rough shape of a wing that only needed some quick attentions with a belt sander (a marvelious tool, no home should be without one).

A simular technique could be used to extend kit wings or streach fuselages. I'll have photos when I do some 1/24 and 1/18 Ta 152 wings, WEEE!

[Derek B]

Nice tip Steve, I look forward to seeing the photographic evidence...I have quite a few very large wings to scratch build, so this could be the answer!

 

Many thanks

 

Derek

[mattlow]

Hi Steve

 

What is drafting film?

 

Matt

[JCote]

Ditto that question for me.

[stevegallacci]

First, it doesn't have to be drafting film, any thin and flexible plastic, ideally thin enough to bend almost under its own weight, or for that matter, paper or thin card stock (though the resin may soak into that a bit, preventing an immediatly smooth surface).

"Drafting film" is ususally a matte finished mylar plastic sheet that draftsmen used in the long ago days before CAD, when pencil or ink was manually applied to drawings.

In any case, a sheet of material that will take a bend along its length and hold it long enough for an application of resin to cure on the cuved surface, creating an approximate half an airfoil.

If you want to get fancy, you could build up external formers to make the curved surface better represent the foil shape and or make up inserts to displace resin where you don't want it for wheel wells or some such.

And it doesn't have to be a solid mass of resin. Rolling the resin around in the mold as it cures can lay a layer of thinner resin over a wider area, so you can create thin shell halves or as the skin layer cures, fill the middle with resin with a lot of microbeads in it to reduce wieght on a solid wing.

With some of these urithane resins that kick in a minute or so then pretty much fully cure in about 20 to 30 minutes, you could have a rough wing made up in no time and not have to worry about warping wood or filling wood grain or foam holes. And if you need to add some mass to the basic shape, just lay some more resin on it, as it will ususally stick to itself okay.

[mattlow]

Thanks Steve

 

I've got some of this stuff. Never knew what it was actually called thought it was a sort of plasticised tracing paper. I assume from what you say that the resin doesn't stick to the drafting film?

 

Thanks

 

Matt