What risers have different rings and why?

[bootlegtrader 0]

I have seen risers where the middle ring is not a circle, instead it is oval shaped and has an extra piece of metal in the middle. (almost like a figure 8, but not indented in the middle) What are these for? What is their benefit? Thank you.

[likestojump 3]

from the horses mouth : http://www.flyaerodyne.com/download/miniforce.pdf

[g2gjump 0]

Quote

I have seen risers where the middle ring is not a circle, instead it is oval shaped and has an extra piece of metal in the middle. (almost like a figure 8, but not indented in the middle) What are these for? What is their benefit? Thank you.

The purpose is to increase the mechanical advantage of the middle ring to make cutaways "easier"

In all actuality if you increased the length of the white loop. The same effect will be achieved.

[RiggerLee 61]

There is no substitute for increasing the length of the lever arm. Ordinary mini risers really are not a good design. The tollerances are too tight. The mecanical advantage just isn't there. Booth actually had it right in the begining with the big rings. The aerodine riser is the smartest thing to come along in a long time. And frankly I don't know why it hasn't caught on. Pattent? If I was them I'd be selling rings to every manufatorer out there. If I was building rigs I'd be paying an extra $5.00 a rig to use them just like people used to do to Booth before his pattent ran out.

And by the way, no, I don't work for them. Not a dealer. No motive here. But I am a good enough engineer/rigger to actually know how the math on this works. And I'm not just talking theoretical shit out of my ass. I've actually seen risers break there in the real world. Eather snapping the tape on the small ring or tearing it lose.

Lee

Lee
[email protected]
www.velocitysportswear.com

[airtwardo 6]

I've actually seen risers break there in the real world. Eather snapping the tape on the small ring or tearing it lose.

Lee

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_attachment;postatt_id=88513;


...me too!

~ If you choke a Smurf, what color does it turn? ~

[g2gjump 0]

Quote

There is no substitute for increasing the length of the lever arm. Ordinary mini risers really are not a good design. The tollerances are too tight. The mecanical advantage just isn't there. Booth actually had it right in the begining with the big rings. The aerodine riser is the smartest thing to come along in a long time. And frankly I don't know why it hasn't caught on. Pattent? If I was them I'd be selling rings to every manufatorer out there. If I was building rigs I'd be paying an extra $5.00 a rig to use them just like people used to do to Booth before his pattent ran out.

And by the way, no, I don't work for them. Not a dealer. No motive here. But I am a good enough engineer/rigger to actually know how the math on this works. And I'm not just talking theoretical shit out of my ass. I've actually seen risers break there in the real world. Eather snapping the tape on the small ring or tearing it lose.

Lee

Very good point Lee.

Riggerrob was my examiner and told me about increasing the white loop. But yes the areodyne ring is a step in the right direction

[RiggerLee 61]

He's talking about a slightly diffrent issue. I don't think icon risers reduice pull forces on a cutaway that much. That's sales bull shit. What they do is reduice internal forces in the riser.

He is right in that hard cutaways can be caused by tension in the white loop pulling the cable into the grommet on the houseing. It acually doesn't take that much to kink it through but even before then you can have a very hard pull. The real issue here is the houseing comeing under tension. That should not happion and you'd be surprised how many rigs have a problem with it. There are ways to deal with it. Longer houseings. Building the houseings so they can float a bit. One solution is a longer white loop. Assuming that it's not so long that compromises the third ring it is one way to put a little more slop in the system and give a rig a chance to cut away when for what ever reason, streatching of the harness, torn stitching, etc the houseing tryes to come under load.

One other thought. Just putting icon risers on a rig actually lengthends that distance slightly. So in theory if the rig was margional to beguin with you might actually create this problem and cause a hard cutaway. Just one more thing to think about in terms of compatability.

Lee

Lee
[email protected]
www.velocitysportswear.com