I'm having a go at my first scratch build. Being a big fan of the predator, and not having a glider type plane yet, I decided to give this one a go:
http://rcfoamfighters.com/blog/?p=950
The plans recommend 3mm foamboard, but that would involve buying it, eh?
In my quest to find decent foam, I noticed the recycle bin at a local whitegoods store and asked if I could help myself. Unfortunately the only stuff they had was a few long, right angled pieces of EPS and a 90x90cm square of lower density crap (the kind you can't really take a sander to). A refrigeration mechanic friend had a solution for me however: a nice big piece of good quality EPS with just enough flat, straight foam for the wings and a thick part for shaping the nose. The wing foam is/was 16mm thick and the lower density stuff is about 19mm.
The wings took shape pretty easily after drawing where the thickest part would be with a marker. The good quality EPS was happy to be sanded and I also used a scalpel to help shape it. The fuse is going to be quite thick but easily replaced if it affects performance too much.
Instead of buying carbon rods for the wings and stabs, I cut down a bargain carbon fibre fishing rod. The thinnest pieces went into the stabs and the thicker parts went into the wings, interlocking in the middle to keep the dihedral. The wing rods extend just beyond the ailerons.
And that's about where I'm up to. I've been using HK 4-6 minute epoxy to put it together and have run out. I don't buy the stuff from the local stores anymore, as it's literally ten times the price... I have to order the servos, pushrods and horns anyway, so the project might be on hold for a bit.
http://rcfoamfighters.com/blog/?p=950
The plans recommend 3mm foamboard, but that would involve buying it, eh?
In my quest to find decent foam, I noticed the recycle bin at a local whitegoods store and asked if I could help myself. Unfortunately the only stuff they had was a few long, right angled pieces of EPS and a 90x90cm square of lower density crap (the kind you can't really take a sander to). A refrigeration mechanic friend had a solution for me however: a nice big piece of good quality EPS with just enough flat, straight foam for the wings and a thick part for shaping the nose. The wing foam is/was 16mm thick and the lower density stuff is about 19mm.
The wings took shape pretty easily after drawing where the thickest part would be with a marker. The good quality EPS was happy to be sanded and I also used a scalpel to help shape it. The fuse is going to be quite thick but easily replaced if it affects performance too much.
Instead of buying carbon rods for the wings and stabs, I cut down a bargain carbon fibre fishing rod. The thinnest pieces went into the stabs and the thicker parts went into the wings, interlocking in the middle to keep the dihedral. The wing rods extend just beyond the ailerons.
And that's about where I'm up to. I've been using HK 4-6 minute epoxy to put it together and have run out. I don't buy the stuff from the local stores anymore, as it's literally ten times the price... I have to order the servos, pushrods and horns anyway, so the project might be on hold for a bit.