Frame Stress From High Winds

[kairusan]

I'm curious as to what parts of a 1.5's frame — the verticals or the leading edge — receive the greatest amounts of stress from high winds. I've done some searches on the board and have found some conflicting opinions; most people seem to say that the leading edge takes most of the stress and the verticals absorb very little, but there are a few contrary opinions (including one from the Great Barresi himself, if I am not mistaken). Perhaps a bit of informal internet democracy (with commentary) is in order, so that this eternally vexing question might at last be resolved once and for all? Perhaps not? You decide.

[portlandflyer]

Reef - I'm in that same boat!! No "greenies"!!

[Reef Runner]

Reef - I'm in that same boat!! No "greenies"!!

Is there suppose to be a difference I haven't really seen anything on the Rev website about them

[portlandflyer]

The site hasn't been updated in a while from what I can see!! The "greenies" are supposed to be "stronger"?? Kent has a post about them (AWOC), and some pics taken!! I'm going by the comments on this forum, myself!!

[Reef Runner]

The site hasn't been updated in a while from what I can see!! The "greenies" are supposed to be "stronger"?? Kent has a post about them (AWOC), and some pics taken!! I'm going by the comments on this forum, myself!!

I'll check it out.................though, I think it's going to take more than a set of rods, to help me !!

[portlandflyer]

More practice!!!!!!

[flt101]

I have a nice, accurate digital scale that covers this range of weights. Now, if anyone would like to send me a set of each, I would certainly be glad to weigh them and let you know...

Pete, I mailed them out this morning overnight express for accurate weighing, it's getting to be that time of the year so upon returning them, don't get them confused with pussy willows.

[Felix]

Hey, how about me ? Just kidding Pete. Why does "Felix" want the weights of the race rods? Is it just because he sees a difference in their performance, or is it a weight thing?

I am merely curious about any weight difference between Race and Green Race rods as I do find an apparent 'visible' and tactile difference in the flex when the frames are flown in similar sails in close proximity as was the case yesterday. I switched frames in the kite that I was flying and sensed that the LE stayed straighter with the green rods. Now this may not be so good for directional stability and the probably small keel effect of the upright spars but somehow the quicker snap back to an 'apparently' not stressed frame/sail combo felt better.

Slack sails and bendy spars just do not feel good to me but I am not keen on heavier spars! <grins>

Fighter kites with bamboo spars are sheer magic, of course, as it is possible, for those that know how, to adjust the flex of the bamboo on either side of the kite in order to ensure that it will fly in a straight line...

Felix

[flt101]

I have some green rods at 14 grams some at 16 grams, most of my black race rods run around 14 grams, I have some 2-wrap rods at 12 grams and some as high as 16 grams, those are all without ferrals, the lightest frame I have for 5 rods is a 2-wrap frame with a total weight of 72 grams. So I'm thinking the weight of rods depends on who's running the machine and the time of day, or day of the week type stuff.

[Reef Runner]

I have some green rods at 14 grams some at 16 grams, most of my black race rods run around 14 grams, I have some 2-wrap rods at 12 grams and some as high as 16 grams, those are all without ferrals, the lightest frame I have for 5 rods is a 2-wrap frame with a total weight of 72 grams. So I'm thinking the weight of rods depends on who's running the machine and the time of day, or day of the week type stuff.

That's exactly the point that I was trying to get across, in my earlier post >>> " P R O C E S S ~ V A R I A T I O N "

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Couldn't Revolution supply you with the actual weight, of the different rod types? Weighing one individual set of rods, really isn't very accurate, as I am sure there is a bit of variation, within individual rods, as well as from rod to rod. The best case scenario, would be for someone, with access to lots and lots of rods, to weight at least a 25, or 50, or even 100 rods, all at one time, and then do the math to come up with a realistic average weight per rod. Then you need to do the same thing with the ferrules, which are used in the center sections, so that two of those weights, could be added to 5 of the rod weights, to come up with an accurate weight for a set (whatever set you may be interested in)..............

Seems like some information, that the quality control area, at Revolution Kites, should have privy to, (or Ben), if that isn't proprietary information...........

Just a suggestion.............

~~~~~~~~~~~~~~~~

So what's going on here? Is the manufacturer actually making the correct product, as the specs call for ? I know for a fact, that 14 to 16 grams difference (2 grams or 14.3% variation) in one product, and 12 to 16 grams difference (4 grams or 33.3% variation), would NOT be acceptable, in most manufacturing situations. So what's the point in having specs, and labeling rods, with this kind of variation ? I'm just curious if anyone really knows, what we are getting? Surely, someone has got to have their eye on the "ball", here, or at least be aware of what is being manufactured.

I'm not trying to be critical, here, but assuming that "hyzakite's" weights are correct, something is bad wrong, (IMHO) !!

[johnnmitchell]

For me, being one of the most experience REV fliers out there, it really does not matter to me if the rod varies 2 grams either side of 14 grams.

Can I notice the difference in how the REV flies? No!

[pwmeek]

I'm beginning to suspect that for "flyability" it would be the flex-under-load that makes the most difference (within a given rod category). Let me play with my 3-wrap and 4-wrap rods and come up with a "standard" for distance and weight that deflects rods of different classes without over-stressing them. I'll get back tomorrow with some ideas and photos.

[Reef Runner]

For me, being one of the most experience REV fliers out there, it really does not matter to me if the rod varies 2 grams either side of 14 grams.

Can I notice the difference in how the REV flies? No!

Hi John,

I couldn't agree with you more, and I surely can't claim, any where near the experience, that you have. I was really just commenting on the level of variation, which I really don't understand, nor do I think it should exist, to that extent, anyway. But, as long as no one has a problem, I suppose, you get what you get !! It still doesn't seem right, though !!

[Felix]

For me, being one of the most experience REV fliers out there, it really does not matter to me if the rod varies 2 grams either side of 14 grams.

Can I notice the difference in how the REV flies? No!

Hi John,

As I said, I was curious about the relative weight whether it has an impact or not. The different flex characteristics are much more important and can, in my experience, be clearly 'felt' and seen in the curvature of the LE.

I would note also that experienced fliers may have the ability to compensate for all sorts of 'differences' in configurations of lines and spars. <grins>

Felix

[katrina]

I have some green rods at 14 grams some at 16 grams, most of my black race rods run around 14 grams

I had to go weigh my black race rods after reading this. They are 13 g each, using a digital scale which measures to the nearest gram. All four together weigh 52 grams, which supports the individual measurements.

2 wraps: 14.6 g (averaged; weighed all 8 and divided), mostly 14g individually, but one 15, and 2 were 16 (no, not the centers!) And here I'd thought my 2 wraps were lighter than the race. Not so.

3 wraps: 18.3 averaged.

I also weighed complete sets, and found that sets of 2 wraps and black race rods weigh the same! 77g. The race center is 4 g heavier than the 2 wrap ctr, which makes up the difference. A set of 3 wraps weighs 103g. Now I know the whole point was to compare green to black race, but I'm sorry I don't have greens.

[Felix]

I had to go weigh my black race rods after reading this. They are 13 g each, using a digital scale which measures to the nearest gram. All four together weigh 52 grams, which supports the individual measurements.

2 wraps: 14.6 g (averaged; weighed all 8 and divided), mostly 14g individually, but one 15, and 2 were 16 (no, not the centers!) And here I'd thought my 2 wraps were lighter than the race. Not so.

3 wraps: 18.3 averaged.

I also weighed complete sets, and found that sets of 2 wraps and black race rods weigh the same! 77g. The race center is 4 g heavier than the 2 wrap ctr, which makes up the difference. A set of 3 wraps weighs 103g. Now I know the whole point was to compare green to black race, but I'm sorry I don't have greens.

Thanks for the information anyway. Maybe someone will come by soon with the weight of a set of green rods. As I said, it seems to me that the flex of the rods is important! [EDIT actually the weight of green rods is pointed out up-thread as being variable as with other rods so 'flex' is the concern...]

Felix

[Felix]

I'm beginning to suspect that for "flyability" it would be the flex-under-load that makes the most difference (within a given rod category). Let me play with my 3-wrap and 4-wrap rods and come up with a "standard" for distance and weight that deflects rods of different classes without over-stressing them. I'll get back tomorrow with some ideas and photos.

Hi Pete,

Did you post your results? I seem to have missed them...

Thanks

Felix

[pwmeek]

I only have 3- and 4-wrap sets (plus an elderly Rev I set; dunno how age affects rods) so I hadn't gone beyond designing a repeatable/specifiable test for flex under load.

I can run some tests, and post the distance between supports, a suitable load weight, and a method of measurement.

Sorry for not getting with this, but I've been fairly seriously distracted: I'm going in for surgery in a couple of weeks to remove a small cancer from a kidney. Doctors say it is easy surgery, generally successful, and short recovery (with no chemo or radiation needed), so I am treating it mostly as a nuisance. However, the number of required pre-op conferences, meetings, consultations and tests are quite time-consuming. I expect to make it to Grand Haven on May 20-22, so you can see that I'm not worried.

[fungus]

Hi Pete

good luck with the surgery

Hi All

a very interesting thread, i'm a simpleton ie exp frame is too bendy SLE is too stiff, anything else i trust REV,

SUL - 2 wrap , STD - 3 wrap, VENT 4 wrap or black race, i want to be able to grab a kite from the bag and fly

fungus

[ahofer]

Best wishes for a speedy recovery, Pete.

[Felix]

I only have 3- and 4-wrap sets (plus an elderly Rev I set; dunno how age affects rods) so I hadn't gone beyond designing a repeatable/specifiable test for flex under load.

I can run some tests, and post the distance between supports, a suitable load weight, and a method of measurement.

Sorry for not getting with this, but I've been fairly seriously distracted: I'm going in for surgery in a couple of weeks to remove a small cancer from a kidney. Doctors say it is easy surgery, generally successful, and short recovery (with no chemo or radiation needed), so I am treating it mostly as a nuisance. However, the number of required pre-op conferences, meetings, consultations and tests are quite time-consuming. I expect to make it to Grand Haven on May 20-22, so you can see that I'm not worried.

Best wishes for a speedy recovery.

Felix

[portlandflyer]

My wishes go with you!!