Hi guys, first scratch building project here.

I've been trawling through the forums for a while now building up my references for different foam shaping techniques and I'm pretty well sold on heat shaping of thin foam with a inside & outside coat of fiberglass to give it structural integrity.

My ideas at the moment are to create an internal skeleton of bulkheads for the main body then to shape foam around it.

I've gotten my hands dirty with Sketchup and it's been immensely useful to get the scale cross sections needed for the overall shape.

The only question I have at this point is.. using the foam shaping technique that I am, how important is the internal "skeleton" of the plane?

At the moment i'm creating plans for a 1/20th scale F-18, and i've created internal cross sections for every 70mm of the craft (14 in total). Is that too close together or too far apart?

Thanks in advance, i'll post pics as soon as i'm far enough in that i'm confident that the technique will work out.

Hi !

If you want to build a shitting with 3mm depron i think you can add space between your bulkheads or, better, if you can build your fuselage as 2 half parts, use all your bulkheads and once the shitting will be done try to remove some bulkheads (may be half of them) where they are not important for the solidity of the fuselage.

Even with foam, keep in mind that lightest is the weight, better your plane will fly.

You can also visit the "Pusher Prop jets" sub-forum you can find a lot of interesting things about F-18.

Best regards

Thanks Dreamcatcher, that's a good idea! I'll increase the number of "ribs" to use as a guide during the initial construction then remove a heap after i've got the shape and i'm happy with the strength of the structure.

I've just printed out the length ways cross section so i'll see if i can start construction tonight.. pics up soon!