DIY onestrut kite

[kjorn]

Open source older designs? Like Nitro 5 etc? Will thankfully be embraced by the Chinese... especially if they can be marketed as such.

Like they couldn't just unpick a Nitro 6 and take measurements of all the panels? It's called reverse engineering and happens all the time.

[downunder]

Who are "they"?

I can't do that, can you? If you know how, do share...

[Hansen Design]

While conceptually possible, picking apart a kite and duplicating the components is practically impossible, especially the canopy which is to some extent elastic. It would require a sophisticated workshop and a very time consuming and precise process. And, copies can never be better than the original, even when accurately done. At best, one would be at a starting point to embark on further development without knowing how the kite got to it's present state and what was done to get there. Though the Nitro6 looks essentially the same as the Nitro5, it is entirely different and nearly every seam was modified to reshape the canopy and revise the LE tube. This work was all done outside of a CAD environment using hard-earned experience with traditional sailmaking techniques and previous testing to achieve the desired improvements. Unless an entirely new design was generated with CAD software, a Nitro7 would require a similar effort.

[BWD]

so would a better development path be:
1) have a proto/sample made, test, tweak and record changes, mod CAD to equal/approximate your changes, send file for next proto,
or
2) create 2 or more CAD files for protos, ID the best proto by testing, tweak its CAD file a couple of ways, get 2 more protos, A/B test, repeat...

I'd guess (2), especially if you have a production commitment/schedule or established relationship with factory, but maybe (1) for a blue sky design/new project....

Curious if you have any comments, Mr. H.

[Hansen Design]

Hello BWD:
My approach is your #1. Occasionally, several identical protos with one variable change. This was used on the Legacy to optimize slack. I see in promos for some brands about dozens or even hundreds of samples being made. Pick the best and bin the rest. Expensive since most wind up in the dumpster. And, with a little 'tweaking' one might have been better than the originally chosen one. It is surprising what a little time behind a sewing machine can do. Years of re-cutting racing sails and kites has convinced me that 'hands-on' involvement is cost effective and more informative than drop-down menus, mouse clicks and waiting for a new sample.

[BWD]

Certainly makes sense.
I have a lot of respect for people who can take ideas straight from digital to physical, but having a feel for the process and connecting the dots by hand, so to speak, seems still very important to many of the best designers/shapers. Reassuring to a weekend hacker.
I keep my sewing misadventures to the minimum but when building boards (and other things) I start on paper, try to nail the important numbers in CAD, output offsets or templates, then fair and build the old way. Wish I had time/space money to change single or paired parameters, but economy forces one to get good at guessing. Sorry if I'm rambling, best wishes with the new projects/ventures.

[downunder]

While conceptually possible, picking apart a kite and duplicating the components is practically impossible, especially the canopy which is to some extent elastic. It would require a sophisticated workshop and a very time consuming and precise process. And, copies can never be better than the original, even when accurately done. At best, one would be at a starting point to embark on further development without knowing how the kite got to it's present state and what was done to get there. Though the Nitro6 looks essentially the same as the Nitro5, it is entirely different and nearly every seam was modified to reshape the canopy and revise the LE tube. This work was all done outside of a CAD environment using hard-earned experience with traditional sailmaking techniques and previous testing to achieve the desired improvements. Unless an entirely new design was generated with CAD software, a Nitro7 would require a similar effort.

Why is it impossible?

Put it this way, what are the canopy tolerances for any kite out of the factory? Are the tolerances in 1/10 of mm? 1mm?

If the tolerances are not that strict, and I can't see it as that strict, a few mm (cm?) would not matter that much.

Also, when I think of the kite, the black fabric is probably expanding due to a heat much more than bright fabric.

Do we know how much is expanding (due to tension as well), and how much are the tolerances relevant in this scenario? The Flysurfer is claiming that the kite is based on pre-stretched calculations somehow, so maybe that is 'built in' the kite.

I think for an DIY it is possible to make 'exact' copy, providing the expectations for such kite are adjusted.

D.

[Hansen Design]

practically impossible

Meaning: very difficult

While conceptually possible ... It would require a sophisticated workshop and a very time consuming and precise process

Even if able to pull apart glued and sewn seams without stretching the pieces, holding them dimensionally secure in place and digitizing them or creating hard patterns by copying them by hand is IMHO very difficult, or 'practically impossible.'

[downunder]

Ok

If using a vacuum table, with led light underneath, do I need to take apart the canopy? Providing the struts are removed, it is a see through I think. That is how I would do it.

Was this ever attempted?

[kitexpert]

Canopy of a kite is 3-D object, it has double curvature. If you try project it to 2D you get some projection which is anything but accurate.

Tolerances in a kite are not extremely critical. But if you have a small error on each part it adds up resulting very different shape than what was designed. Also symmetry is quite important, also for cutting (fabric orientation).

I don't think to copy an existing kite is a very good idea. But it is possible to try to learn some basic parameters like strut diameters, AR, how flat/cambered canopy is etc., and then try to design a kite which might fulfill your expectations/idea of a kite you would like to have. However you can't find any "correct" value for anything.

And if you had kite copied, how would you make it matching CAD model to alter the size and perhaps trying to develop it further?