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After having a talk with a friend of mine I decided to make a bridle that has a floating pin on the bottom. The idea behind this is that if the bottom pin locks for any reason the pull force will be passed on to the top pin and the top pin will get pulled. Once the top pin is out the pack tray will separate at the top and close at the bottom making it easier for the pin lock to clear. I have been using this method for the past 20 or so jumps and I have had good results so far. 2 jumps ago on a 450 foot B I was using a 42 toxic, 280 blackjack with a gargoyle. I took about a 1/2 second delay (yea yea yea I know stop being a pussy) I had had about a second and a half hessataion. I am 50/50 on this next part but I'm sure I felt the top pin pop first and then the bottom. I had 30 right and landed fine.

Other jumpers that have seen this bridle think it's fucked/I'm fucked. I feel really comfortable jumping this set up but that doesn't mean I'm not missing something. Does anyone jump this type of bridle or know someone that does? I would love to hear some more plus/minus augments as to why I should/shouldn't use it. Maybe I'll learn something I don't know.

Vertex containers used to come with a floating lower pin. I have a friend who jumped a Vertex for years and was very happy. Also I did a few jumps with a Vertex with floating pin and worked beautifully every time. Sometimes you can see that the bridle ran through the pin a little. It is true that it looks strange the first time you see it but has been thouroughly tested in the field. Maybe somebody with more experience can explain if there are some cons. If you made the bridle yourself and you are not a rigger it would be advisable to have it inspected by one just to make sure everything is OK.

Good to know they have been tested out lots before. Yes I made it myself. I copied the design on the bridle I had but I just left one pin floating. Everything is fine with the build quality and it gets inspected after every jump.

A few of Tom's student rigs have floating bottom pins. Maybe he has some feedback here, but my experience and intuition lead me to believe they are actually a pretty clever idea.

Tom is the one that have me the idea and I made it in his classroom when we were on weather hold. From what I can see there are no clear draw backs. If I remember right Tom said more people don't use them because the idea/look of it freaks them out. That has been the reaction of everyone that has seen it so far.

I was just wondering if there were any good reasons why not to have it aside from gear fear.

Pics please! Those that wish to gain knowledge from these threads would love to see this configuration!

Yeah I'd have jumped one of those floating pin rigs there too, and I didn't go in.

Maybe something here?

http://www.blincmagazine.com/...owthread.php?t=22294

Darcy, I made mine at the same time and I've put around 75 jumps on it. While packing I've found the floating pin just an inch or two from the fixed pin a number of times. If I jumped one of the rigs that allows for a pretty serious bottom pin lock, I'd definitely want one of these.

Only real downside I can see is it wears out the bridle faster right where the pin twists and rubs as it moves through the bridle on opening.

That's because jumpers these days don't know their history. As for the floating pin I believe it existed while the Prism was in production - take a Prism bridle, loop on a 2nd pin and voila you have a Vertex bridle (some old fucker may know more).

Edit: I believe the floating pin made an appearance in skydiving too.

We where a couple here jumping vertex with a floating pin bridle.
Many of us (included me) had some weird hesitations on opening, so we all (except Frank who was still jumping it in 2010 http://www.base-jump.com/...msg8572.html#msg8572) decided to sew the floating bastard

I can't say that these hesitation on opening were due to the floating bitch, but in doubt we sew it, and after that no more trouble ...

I saw Ulrik make a floating pin bridle on your course Tom, but i never got to ask about it. I can think of two positive sides of this,

1) tension on pin is to great to pop 2) second pin is stuck somehow. Am i correct?

But would this not affect the delay of opening? And greater the risk of pin lock (if fabric wraps around the second pin e.g?).

It looks really interesting but i can find so little information about it.

I doubt that would work, because it would be very difficult to get the sewn end of the finished 1 pin bridle through the eye of the pin. It should be easy to grab a bridle and try it though.

If you measure the force required to extract the pins with the rig packed and sitting on a floor, and then re-measure them with the same rig on a jumper curled into a ball (with the harness tightened down), the force required to extract the bottom pin can change dramatically. The force required to extract the top pin varies much less. Given this, it would make sense to stage the pins such that the top pin always extracted first, thereby loosening the pack tray and making it easier for the bottom pin to extract. Better yet would be if there was a way to make the top pin extract first if the bottom pin was overly tight, the extraction would occur in the optimum order (looser pin first, then tighter pin second after the tray has loosened a bit).

The floating pin basically achieves this goal of staging the extraction to reduce issues with pin over tightening due to body position during deployment.

That said, issues caused by this are extremely rare. The biggest reason we've ended up with floating pins on some bridles here is that we had a couple of them and students would freak out when they saw them, so we started floating a pin when we replaced bridles, so that students would be exposed to this alternative system (and therefore learn about it).

Thanks for the insight Tom!
I see your point there regarding tension on the pin while geared up. But wouldn't it be more practical to just make a longer loop?

That depends on the length of the loop.

Usually the issue isn't the length of the closing loop, but rather the tension created by the distribution of the pack job (and the tightening of the harness).

No shit. The finished measurement would have to differ also. But if the bridle was 95% complete then they could simply add the pin (or not) and finish to the appropriate 9ft measurement. That way you don't have to stock 2 different bridles, just 1 pile of blanks that get finished off according to orders.

I can't see it saving more than a few minutes. And the materials cost is negligible, so building specific bridles for each rig doesn't seem like it would save time or expense very much.

Sewing the pin onto the bridle and sewing the end loop would take, what, maybe 5 minutes? And just sliding the pin on and sewing the end loop would probably take 3 minutes? I'm not sure the time savings would be worth the hassle of completing bridles for each rig type separately at the time of order. It would probably make more sense to just sew up a big stack of each type to keep on hand.

I build bridles pretty regularly here, and even doing each one individually is very fast. A proper gear manufacturer would probably have the time down so far that it would be a negligible consideration.

pics? anyone? that blinc link had nothing

Yes, pics would be good. The way I'm reading this thread, including this...


...reminds me of the mechanics of the shrivel flap on a velcro rig. The mechanics are similar even though the reasons for them are different.

Here's my floating pin bridle.

Under normal conditions how much does the floating pin slide on opening? Or does it not at all?

SD it seems to only get pulled an inch or two. SU it gets pulled quite a bit more, sometimes just a couple inches from the fixed pin. Not sure if that's due to the pull direction (in a track) or increased pull force.

It depends a lot on body position.

Has the difference in pull force of the bottom pin been measured before and after top pin extraction?
I would also assume that the bottom pin extraction force would be reduced after top pin extraction... but is it significant?

Bump.

I asked myself the same question when I saw the setup.

Also, could the the top pin, after extraction, somehow be thrown towards the bottom pin and cause a lock (or resistance to the extraction) by getting somewhere in between the pin, closing loop or flap holes?

Sad news this week. Sad days. :(