Absolutely love the gismo! The vertical on it is what I was thinking of for the design of my tail. Something that can be taped on or possibly use magnets. Peter wick uses magnets on one of his planks and says it works great. He even has one that uses LEGOs to attach the tail.
I actually like the planform Jeremy came up with a lot. It's a bit foamwirecuttery but It's cool. The lofts on the wingtips for the Echo require using guide lines. at first they were somewhat tricky but only because of how the radius is made to form the tip. It didn't want to loft when you tried to attach it to the guide. Fun learning how though.
I watched some videos on the PPS-Cf filament and wow is it pricey! But awesome! Maybe the PETG or PETG CF is the way to go.
I have had a laser for a while but had limited use of it because i didn't know anything about using CAD. Maybe I'll try to laser cut some spars myself .
With Onshape you can add an airfoil very easily but you can't scale it in the free version if it's a DXF. The nice thing about the generators is that they scale between 2 points so anywhere along a planform you can position them and automatically scale them. Probably the same for other programs.
Thanks for the suggestions
Watching wth interest. Always good to see the logic people apply to new designs.
My two cents' worth.
IMHO The rearward central fin is the way to go, Kelly and it looks like all are headed that way. I have used this layout many times on early designs (many) in the late 80's, and basically the further you can get it back the better - within reason - and that's why I used a single detachable 'stinger'. Further back also allows you to reduce the fin area. But as that method also leaves the vertical fin liable to damage, I used a mechanical fuse - in my case, the fin 'boom' was taped on with an internal balsa wood rod which would break in the event of a bad landing. But having said that, if I had had rare-earth magnets, no doubt I would have used them. Dayum, those things are strong these days!
Oddly enough, I don't think I ever broke one of my 'balsa fuses' except for one time while mishandling the model getting it out of the car. Dooohhh! I found that in use, the flying wings are really rugged. Apart from the fin, they are monolithic and pretty hard to damage.
I think the designs here are all pretty good, though there is a lot to be said for guiding the isobars over the centre of the wing - i.e. inceasing the chord at the centre to keep the spanwise flow down a bit, and the pressure up on the flaperons like Tim and Peter's
Gizmo design. By the way, the larger 2M versions of the same design that Tim made were really good too.
As an aside, I was with Tim in the Brisbane area of Australia, when he was bungee launching his Gizmo with a REALLY powerful medical rubber tube that gave almost supersonic speed launches to a couple of hundred feet. One time, just as he was going to let go of the model, the bungee anchor failed, and the whole caboosh shot back and hit him in the chest with an almighty thwack - he was black and blue for days!
It's never been categorically proved, but it's really easy to see that, technically, the flying wing, if correctly designed, should be the fastest of all slope planes. I always hoped to make a really quick wing for MoM or F3F - they are a bit hard to see at times when flying, and would probably take quite a bit of getting used to and maybe need some new flying techniques, but with a bit of brain bashing on the design side and practice on the flying side, it should be unbeatable.
Carry on the good work!
Cheers,
Doc
