New Release?
Posted: 2012/01/26 16:01:21 UTC
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What, you didn't think that thread was long enough as it is? =)Tad Eareckson wrote:I'll have some more comments in the "Releases" thread regarding this two point primary release assembly and the bridle/release system Antoine posted on The Davis Show.
(From here)Tad Eareckson wrote:Joe was smart enough to take the most critical bend out of the equation.
virtually, it's clearly not an issue but.. as we are all quite obsessive here you just have to install a pulley on the corner downtube/basebar and you will pull the cable straight..it's going to have to bend.
I figured that one three hundred post Kite Strings releases thread that goes somewhere is better than ten thirty post Jack and/or Davis Show releases threads that don't.What, you didn't think that thread was long enough as it is? =)
Yeah, I meant the acute angle turn you hafta make if you follow the control frame corner and run the housing all the way to the basetube. Joe eliminated enough of it to make me happy.If you're running a cable vertically down a downtube and your pulling it horizontally on the basetube, it's going to have to bend.
So - like you're about to say - take up the slack before you need to.One thing I noticed in making this video is that my hand moves pretty far just taking up slack in the cable before the cable pulls on the release.
If whatever's clamping the cable to the downtube is narrow enough to allow the housing above to bend outwards while the housing below is being pulled inwards the bend will get softened a little bit - otherwise I'm not seeing that extending the housing is doing anything and I think, even if it is, that ten centimeters is excessive. I'd be inclined to experiment with one centimeter - but this is Joe's baby and you're the one flying it....but I'm not following that...
And only a portion of your hand movement is being translated to bar movement....and the only reason it's not sharper is I'm pulling it across the angled portion of the speed bar.
- There is no VG bearing on that side - just a spacer. But it's easy enough to swap one in.I thought maybe a better way to do this would be to run the cable on the outer side of the port downtube and run the lanyard around a VG bearing, but after looking at it I think the lanyard would contact the bottom of the downtube.
I think Steve's right on this and I'm not worried about Joe's release Tabering on you. The release will work and - even if you hafta move your hand a bit - you don't hafta execute the USHGA "easy reach" and go looking for something while your glider's rolling upside down. You'll be able to maintain bar pressure which is almost certainly gonna be back. (This might be confusing to some of the students who've survived Ryan's Instant Hands Free Release - which requires forward pressure.)You will see that the cable itself can and does work smoothly when the flexible housing is terminated before the small diameter turn is introduced.
That would be the best way to configure this release. BUT......as we are all quite obsessive here you just have to install a pulley on the corner downtube/basebar and you will pull the cable straight..
What makes you say that? I don't think it's slipping.Tad Eareckson wrote:Another biggie is that the housing isn't clamped tightly enough to the downtube and you're not just pulling cable - you're pulling housing.
I am using a hose clamp (as Joe suggested)...I just put the tape there to hold it while I clamped it and also to protect the downtube from any scratches from the clamp. The housing doesn't budge no matter how hard I pull it. If it was slipping, the length of cable from the end to the clamp would be increasing with use (it isn't).Tad Eareckson wrote:You can get a stainless steel hose clamp from the hardware store and form it to your faired tubing.
Yeah, I was looking for a compromise.Tad Eareckson wrote:A better way to do this is to drill a hole in the top of your downtube and run a lanyard inside down to a VG bearing and inboard to your hand.
Looking down at it from the camera on the right downtube (?) it looks like it's getting pulled through.What makes you say that?
Then it probably isn't. I'm probably just seeing it getting pulled more horizontal. (Really looks like it's getting pulled through though.)I don't think it's slipping.
I'm going to experiment some more and see if I can optimize things.
I don't think USHGA allows people to try to optimize things - just to die on releases that have been designed and extensively tested by the reputable manufacturers listed in Appendix IV of the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden who sell the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden.Towing Aloft - 1998/01
The towline release is a critically important piece of equipment. It is the device which frees you from the towline and it must be failure-proof. Numerous designs have evolved over the years--some very good and some not so good. Unfortunately, releases are items that many pilots feel they can make at home or adapt from something they have seen at the hardware store. Two fatalities have occurred in the past five years directly related to failures of very poorly constructed and maintained releases. For the sake of safety, only use releases that have been designed and extensively tested by reputable manufacturers. Listed below are various types of releases available with their attributes and applications.
Looking at my Sport 2, I can't see any reason you could not run a lanyard down the outside of the down tube and around a pulley installed in the corner bracket. (Same place as VG pulley but opposite.)I don't have a problem with the amount of force required to actuate the release, but I would like to minimize the distance my hand has to move.