Sorry, KFm2 as it only has a single step on top.
Bought a few sheets of 8mm EPP foam and built a SuperFly clone (only about 2/3s sheet) based on 24 inch one here: https://www.rcgroups.com/forums/show...light=superfli Go there for dimensions - very nicely laid out.

Ready to maiden, maybe this afternoon. Built one of these years ago and really loved its controllability and fun factor. Also, I have less space to fly in here in my newer location so needed a baseball field size flyer. 230 grams AUW and using a tiny 1806/2400kv motor that I salvaged from a totally useless 800mm wing I finally decided to quite playing with. 800mah 3S lipo. Bamboo spit and a couple of CF spars. Also made control rods out of paper clips and bamboo spits because that's all I had around. Fins are super small but I often fly my wings without any fins at all so used to a little waggle. Cut prop slot too big but oh well, its a throwaway plane. Couple hours work. Maybe laminate it later.

Update Jan 29: would not fly, too tail heavy and too flexible in rear and elevons. So, laminated it front and back and elevons. Now really too tail heavy and took it out on windy day and nothing but crashes. So, moved motor forward and took it out again and it flew but mostly harrier so only would fly when at altitude and got some speed up. Motor spins fast with small prop and no torque so need speed. So, now am waiting on some long control rods and will move servos as far forward as possible and that should solve the problem. At least it is pretty indestructible now with the lamination.

Update Feb 1: flew this morning after moving motor closer to leading edge. Flys ok but tricky to control. Incredible rolls. But 1806/2400kv with a 4.5 prop doesnt have enough torque for a 260 gram wing. Could go to 5 or 6 inch prop to help but I have 2206/1500kv motor which with a 7 or 8 inch prop has massive torque (400 to 600grams) so cut hole for prop but now frame is a little flimsy so need to beef it up a bit, switch motor out and try it. It should harrier no problem.
Update Feb 3: Slightly larger motor, 7 inch prop and motor in front now. Concerned about noise of prop in slot. Will test tomorrow maybe.
Update Feb 6: When I build my own wings it seems I make the same old mistakes. The delta would take off beautifully then do a snap roll into the dirt. Every time. I tried strengthening the leading edges with carbon rods., thinking the wing was warping on takeoff, which it was but no change, rolls into the dirt every time as soon as it got a little speed. Took it home and after inspecting it a bit, saw the horns were loose and pulling out of the elevons. Glued a couple pieces of wood to the horns and now they are rock steady. Ready to try again. But then I got a gout attack and so will be sidelined for a week or so.

would like to see more interested in a cheap flyer for my back yard

Thanks but it is looking like a frankenstein plane now and it is too fast. Laminated thick EPP gets heavy fast. So the original depron plane in the link is probably the way to go. I am just experimenting now with a bigger motor and prop but it won't be pretty. I should just chuck it but I hate to give up and every mod seems to get it flying better so want to see how far I can take it.