ratindahat - 4-5-2007 at 02:54 PM
Hey all.
Here is a depower idea i was thinking about. I'm just curious if this would work. My goal here would be to change angle of attack, and try to keep the
shape the same. Do you think it would work at all? or has anyone tried something similar?
Later,
-Dusty-
Pablo - 4-5-2007 at 10:28 PM
Personally I'd start off with something proven like the Pegas Wing Warp or the UDS(universal depower system) to fit to an existing kite, then once
you've tinkered a bit with proven systems give it a go at playing around with new ideas.
I think you'll find though that those 2 systems are all you really need.
ratindahat - 4-5-2007 at 10:30 PM
I'm just spitballing ideas. I'll probably just buy new kite when i am really ready to buy a depower. Just coming up with some new ideas and was
curious if anyone had tried it.
-Dusty-
krumly - 5-5-2007 at 10:55 AM
Dusty -
Pablos's right, and both the UDS II and Wingwarp/Frenzy systems are common on depower kites. Wing warp/Frenzy uses one pulley, UDS II adds another
pulley or two for smoother camber and angle of attack variation. They basically have the A lines fixed, the brake (or D lines) getting full 1:1
travel, and the pulley stages getting 1:2 and 1:4 as they get closer to the nose. So you get both increased angle of attack and increased camber as
you sheet in.
Both are well explained at:
http://www.powerkite.me.uk/
I'm sure Pablo has mentioned this site in other posts. Looking at your sketch, I'm pretty sure you'll end up with a kinked, accordianed foil. The
much lower pressure near the front of the foil will pull in on the C and D's. Try it, but on a light wind day.
krumly
ratindahat - 5-5-2007 at 05:22 PM
I was thinking that too.. The wing warp idea looks pretty simple in concept, just have to tune it well.
-Dusty-
Pablo - 6-5-2007 at 03:15 PM
The Pegas WW will give you a little less smooth of a depower, but they don't tend to lose that much of the low wind ability of the kite. With the UDS,
they're way smoother, more like a regular depower kite, but they do lose a little more on the bottom end.
ratindahat - 7-5-2007 at 02:07 PM
Now with the WW do you need to run heavy lines for front and rear?
-Dusty-
Pablo - 7-5-2007 at 04:17 PM
When I tried switching my 9m Buster over I used the stock lines, didn't have any problem with the smaller rear lines, probably wouldn't hurt though.
The front lines should still be taking the brunt of the load, the kite will be sort of ballanced on them with the rear being used to tilt the kite.
ratindahat - 7-5-2007 at 04:20 PM
cool. just debating if i want to try it or buy a depower.
krumly - 7-5-2007 at 04:35 PM
Dusty -
If your kite doesn't have the A's grouped to one secondary bridle, B's to another, C's to another, and so on, setting up any kind of depower pulley
system will be pain.
Many fixed bridle kites, I believe ProFoils included, have groups of primary A's + B's +C's pulled to a single secondary. You have no way of
separating them easily without making additional secondary bridles, and determining the lengths of those secondaries is not a trivial task. Be
careful not to undo something without noting how to return it to it's original configuration - the experiment may fail, and you'll want the old kite
back...
krumly
ratindahat - 7-5-2007 at 04:46 PM
krumly, I agree with your advice.
I think i shoudl just buy a depower to start with. :-D
krumly - 7-5-2007 at 05:04 PM
Dusty-
I have an older Kitesurfer XXL that I'm going to try to convert to depower. I have measured all the bridles and the rib profiles, laid it out on the
computer and laid in a new rig. I have no clue if it'll work, but eberything will be reversible.
FWIW, try looking on http://www.ikitesurf.com/buysell/classifieds.pl for used depower kites if you don't find one on this forum. I've scored some good deals there in
the past.
krumly
ratindahat - 7-5-2007 at 05:15 PM
I'll check out the site. thanks