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Perhaps this is a stupid assumption, but would having a smaller diameter pin create less surface area, which would lead to less friction, thereby reducing the chances of a pin-lock with regard to high tension/friction? Also would a more pliable pin material be a step towards improving the pin-lock gremlin?

I've seen a lot of discussion on pin orientation and shape but not so much on pin material and diameter. Is there a reason that the current standard pin shape/material/diameter is used? Also can the same be said for closing loop material? I've heard of guys and gals using cypress closing loop material instead of the standard hollowed out 550 cord.

Just curious as to see what discussion can come of this.

Why would you want less pin tention? I keep my closing loops as tight as I can to increase pin tention as long as there is not lock witch does not happen because of pin tention I want the pins tight incase the cover flap comes open at least for slider up.

Solid point. I should have mentioned that I was thinking more along the lines of low slider down objects.

Got it but my point being that pin tention does not cause hesitation I keep my pin tention the same on the lowest of jumps. You ever felt the power of a 42 at even 20 mph if not hold it out of your window that will Pop any pin tention you have unless something else is locking it.

Smaller diameter? More pliable? Haha! Pitching a 42" PC at 3 seconds and having the pin kink and lock would be my concern. As stated above, pin tension has little to do with locking containers. As stated above, I'm looking for more pin tension for security.

At least in theory, frictional force is not a function of area. Not entirely true, for things like car tires, but for solid objects it more or less holds true.

There has been discussion (and research) on other materials for closing pins. Specifically that yellow Lolon cable that we use for our three ring systems. IIRC, the biggest problem was the threat of kinking/breaking, and the second biggest problem was that it wore out closing loops way too fast. Also, before the pin we use was around, the guy who invented the pin was taking bites of bridle and sticking that through his closing loops (which I think we're some elastic material).

I think the "standard" material for closing loops is not 550, but rather the same material for the white loops on our cutaway system. I'm not sure what the name is. Obviously a lot of people will replace it with 550 though, which works fine provided it is properly constructed.

The theory behind the frictional force, as mentioned above, doesn't strictly deal with surface area. It relies on two factors, the frictional coefficient and the normal force. The frictional coefficient is the interaction between two specfic materials, which we already acknowledged above in the form of the yellow cable, and changing this makes more problems to solve for now. The normal force in this case would be your pin tension, which is the simple fix for what you are looking for. If you want to decrease it, just lengthen your closing loops, and you've solved your problem without creating any more problems to solve.

All that said, I think this kind of out of the box thinking is what drives advancements in our gear, and discussion like this is positive for everyone. As our technology increases, there will be less room for innovation, but we will always have things to improve upon.

If one DID want lower pin tension:
- pack tighter/cleaner canopy
- install longer closing loops
- make loops out cypress line
- lubricate loops with silicone

All of these would be safer and cheaper for
any novice to experiment with than designing,
making, and then test jumping two new pins.

I personally like my pins to be tight; can't find a failure mode with high pin tension. I still do not really understand the scare about pin tension. Only exception would be uber low free falls; however, if I am so low that I am concerned my pins are too tight for a free fall I just static line the object.

Type 2A. Essentially gutted 400lb. Paracord/550LB being Type 3.

Spectra is another option for loops. Significantly lowers friction but lasts way longer than Cypres cord.

Why not use Velcro?

I love my spectra closing loops, but they wear/fray really quickly comparatively and can be a pain in the ass to get my ribbon through. But the pin tension is perfect for me.

I would if I had a Velcro rig. But unfortunately I don't have one....yet.

How tall are you, and how much do you weigh?

What size Spectra? I use 1000lb seems to last fine. Will start fraying if you tear it up with your pull cord though.

5'10" 220 and have a BJ 280.

Ya, I think I'm using 725lb

Also using a length of Spectra as a pull cord will result in less wear to the closing loop.

Much gracias I'll give that a shot

The challenge of pin diameter and radius is that one doesnt want the pin sucked in to the grommet.
take care,
space

I disagree. Using type IIa yith a fingertrapped inserted in the center to fillout opening the closing loop a bit more to insert the pin.
Less wear on trying to.
If one doesnt know how to minimize pull up cord friction I cant help.
I can burn thru a riser with type IIa in less than 3 seonds I think. A half of second through 1000lbs dacron at human speed (much slower than deployment speeds)
Take care.
space