Wondering what most people have on their rings for rings. Small or large. And why you got that size (what's the benefit in your mind).
Timber
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Wondering what most people have on their rings for rings. Small or large. And why you got that size (what's the benefit in your mind).
Timber
I'm not sure if this is what you are looking for but here's my 2 cents.
We build our rigs, at Apex BASE, using the large rings. The reason is simple. The large rings have a better mechanical advantage. Now I'm not saying that the small ones don't work (they do). But when looking at the math the large rings make more sense.
The 3 ring is a level system. The bigger the lever the better the mechanical advantage.
The large 3 ring has a 100 to 1 ratio.
The small rings are half that, 50 to 1.
That means you place 100 pounds at the bottom and the small white loop receives 1 pound with large rings and 2 pounds with small.
Using a releasable riser on a single parachute system is already a fragile proposition. Why use the weaker of the two options?
We've measured slider down opening forces that exceed
6 Gs. Use a 200 lbs jumper and you've got 1200 lbs at opening. Sure this could be split between 2 riser reducing it to 600 lbs per side. But what if it's all taken on one side. The large rings provide a better buffer to a possible failure.
With small rings you also have a substainal compression of the riser material (Type 8 webbing) increasing the wear and decreasing the lever.
There's a couple more small issues but the reduced mechanical advantage is why we make large rings standard and keep small rings off the order form. We have built a few rigs with small rings but only after educating the buyer of the pros and cons. They usually go with the large rings.
If the reason behind going with a small ring is the bulk. Then get a non-detachable riser. No hardware, no handle, the risers are built in like a reserve riser. Again there are pros and cons but for low bulk and security it's hard to beat.
T
Todd,
Great reply! Exactly what I was looking for. Thanks!
Timber
Your post rocks, You do too. I hate mini harness rings.
Take care,
space
What about L-bars ? A popular euopean option.
>>Thanks for posting that Todd, that was interesting to read. Anything to decrease the force on the small white riser loop of life is good.
Didn't Vertigo and Basic Research come before Apex ?
As I understandi it, you're not going to generate a load for a ring to snap on a riser nor is the loop after 50:1. The mechanical advantage only is important when you need to cutaway under load like a spinning mal in skydiving where heavy G's are created and you're fighting the cutaway handle. In BASE you're never going to cutaway under load so it doesn't matter the extra 2x advantage on the handle pull or worrying about the cable sucking through a grommet. You will cutaway in a tree, in the water, or when cops are in pursuit.
To me the benefit is you can use any set of risers on big rings but only mini ring risers on mini harness rings.
both harness rings are rated to 2500lbs.
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Does that mean that I can't buy a new pair of Apex risers if my warlock has mini rings ?
Actually the small ring is failure rated to 3000#, and the large one 2500#. Not that any of that matters since the human body will fail at about one tenth of either single ring. At 255# I've always jumped the small rings and they work fine. Just like Abbie said, the mechanical advantage is only important if you intend to cut away under load, such as in skydiving. Besides, the smaller ones look cooler.![]()
When I was working as a full time rigger, I came across a type 8 (wide) risers with mini ring webbing that failed. Sandy Reid (Rigging Innovation and PIA tech Committee) was doing a study on mini-riser failure and changed the title of the study title to mini-ring after viewing the risers.
Take care,
space
Wow.
What exactly failed and where?
What was Sandy's conclusion?
Thanks space.
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