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I`m just interested if anyone has experience with measured values of pull forces for terminal / subterminal jumps for base rigs? As regards to pull the ripcord pin(s) clear of the locking loop(s). (For reserves maximum allowable pull force is about 22 pounds)

A while back Yuri had posted an
Excel spreadsheet that had the
formulae necessary to calculate it.

When I got my 1st velcro rig I had
a friend drive my pick-up truck w/
me in the back at a given speed
so I can test the pull force of my
pilot chute.

Word is velcro takes 12 pounds
and pins rigs can be tweaked to
be more or less depending on
the type of loops, tension, and
if you lube them like a reserve.

I belief this is due to my school english. Reading this a picture is coming to my mind: some one is packing a reserve sitting on the rig with an oil can in his hand lubing the reserve loop...

What's the meaning of "to lube" in this context?

Ingo

The replies below are better than mine.

The "oil" or "lubricant" is officially Silicone.

My understanding is that, while some riggers swear by lubing their temp pin and reserve pin, Cypres manuals are very specific where the lube should be applied, and talk in terms of friction on the loop.

I gave up lubing my temp pin as I saw no added assistance.

Specifically, in a non-AAD fire activation, the loop has to travel thru 4-8 grommets and the cutter. There is a lot of friction. In an AAD fire, depending on where the cutter is installed, part of the loop still goes thru grommets with a suddenly slack end behind it.

Because the flaps are pulled sideways, the loop does not travel a straight line. Every time a rope has to round a corner (with out a pulley wheel), there is friction. Proof - look at rock climbing belay devices, one or two bends will hold a human. Look at a reserve and you will see that the forces applied are 90 degrees to the direction of loop travel.

The lube allows the loop to slide thru these bends, grommets and cutters.

I have never seen or heard people lubing their BASE rigs, and I would never do it without the manufacture or someone really knowledgeable telling me to do so. The closing loops are not cypres loops, they are not shiny smooth tightly braided round line... And, remember, lubrication also attracts dirt (causes dirt to bond). Dirt adds resistance.

So my learning question is - do people actually do this?

why would someone do this?
sticky liquids won't go near my rigs...
the attraction of dirt would also be my biggest concern.
you can use yo mammas shoelaces if you prime the pins properly.
maybe the green skydiver should keep the lubing stuff to his private life and start jumping. though i'm pretty sure he knows a lot about lubing up...

I have measured various rigs over the years. In my experience, velcro rigs (once broken in) typically take between 12 and 18 pounds of pressure to open. Pin rigs can vary a lot more (depending on loop tightness, body position, loop material, etc). I can get a pin rig down to about 3 pounds with the right loops, a relaxed pack job and an arched body position. With tighter loops (made from a different material), a sloppy pack job and curled into a tight ball, I can get the same rig upwards of 20 pounds.

@ tom: thanx for information

Your name fits you.

Is there data available for snatch force of different size pc's at different delay's?

Theoretical values can be calculated (I believe I've seen a good spreadsheet posted on several forums), but I am not aware of any experimental data being gathered in a methodical fashion.

Cypres lines is just one of many things you can fabricate closing loops from...