cellkites5

Do you know how many people call Kite Studio and say: "I built this kite, (what they really mean is I sewed this skin), now what kind of sticks do I need?": And I say: "hmmm... well how big is this skin? How does it attach to the sticks? What is the aerodynamic shape?"

THEY DID IT BACKWARDS...START WITH:

A. STICKS FIRST:

So how do you know what size sticks to use?

Well, most people guess.

I also guess, but I try to guess intelligently...

Think back to your failures - if 2100’s broke here before as cross sticks, I guess you need to go to 22’s or 23’s or 24’s etc. etc.

Consider disassembly - after all it has to fit in the bag...

If you decide on longerons that are 2 times 32.5 or 65” long - that determines your skin in design step C. It only makes sense, it’s a lot easier to make the skin 1” shorter than it is to make the stick 1” longer.

Look at plans of similar kites and try to get a size starting point. Experience here will serve you well. As time goes on you will learn that cross sticks need to be a lot stronger than longerons.

Remember, double the size of the kite and you quadruple the size of the lift, so the sticks need to be more than twice as long, they got to be 4 times as strong.

I’m sort of paranoid, so here I would do some preliminary weight to lift ratio’s to see if I was in the right ball park, nothing too accurate, just estimate the total # of sticks required, take the total weight in ounces, and that is a number that should not exceed ½ the square feet of the projected lift. I realize this is a pain in the butt step, and most people just wing it, heh, that’s a kite joke. See Topic 3 in the Trilogy, Weight to Lift Ratio’s.

So, we have decided on stick sizes, now to the next design step

B: FITTINGS:

This is an easy step. Pick one from the available list we already discussed. See Topic 2 in the Trilogy, Fittings and How They Work. Just make sure the size fitting you chose matches the size stick you already choose, and that the size stick has a fitting available in that size.i.e.2200 adj. fittings are only available in all aluminum heads with a max. adjustment of ½”.

Once the fittings are selected you now make the next engineering/design step easier.

C. SKIN/GRAPHICS:

Designing the skin is now easier because now you know what you need on the end of the sail to connect it to the stick...

Here the engineering in me makes me create a, to scale 8 x 11 plan, of each piece of the kite. Use your engineering scale & pick the appropriate one that fits the paper - write down the scale you used, so later when you look at the sheet you can find it quickly (it drives me crazy when I forget that part and have to waste many minutes trying to figure it out by trial & error). This is where you add Gibian Loops, Pockets, Insignia corner re-enforcement’s, both under the hem or over the binding, dacron strips on the back side where sticks are going to be to reduce stretch, grosgrain tie down locations, cut outs for bridles, pushers, or cross sticks, rings for bridel attachments or bow lines etc. etc.

Cross check each view to make sure that if in the top view length A = 16”, then that same length A seen on the side view must also be 16”, And, the overlapping re-enforcement’s must be at the same location.

Last thing for design step C is to create an exact size pattern for each needed piece of skin out of oaktag.

Obviously, if the piece is symmetrical the pattern is only ½ size with the top being the right side and the bottom being the left side or visa versa.

I actually lightly spray my patterns with repositionable adhesive, #75 or the new Best Test stuff from Bestine, and then using a light touch with a utility knife, I cut directly on top of the pattern; of course this limits the number of times you can use the pattern, but if you are only building one or two kites, who cares. If this is still confusing you might want to take a look at the Tech Sheet, the Modified Bobby Stanfield Method (HK).

Only other thing that needs to be considered is the sew schedule. What that means is that if you are doing a complicated multi-cell piece you need to be sure the sew machine does not end up inside the center cell, unless it’s absolutely necessary. The key word is plan carefully.

I hope I have made cell kites less intimidating.

Give me some competition, I want to see more of you guys building cell kites.

Remember , anytime you need to discuss a problem, call Kite Studio / Steve / Tony, we are always at 610-395-3560, ready to help.

OK, then everybody have a good day and build lots of cell kites.