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flighty

Curved closing pin material

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Is there anywhere that I could look up the type of alloy that a typical curved closing pin is made of? I am specifically interested in the nickel content trying to track down if I have a nickel allergy. My closing pin necklace (from my old pilot chute) and a gold wedding band have been causing contact dermatitis.

~Cindy~
Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?
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Ya, looking into it a little more, I think I was confusing surgical steel with stainless steel. Bummer, but at least the allergy thing makes sense and I can go from there.

~Cindy~
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They call it stainless steel, you basically have that in 3 large groups.

The most commonly used kind is "300" series stainless steel. generally they become austenitic by addition of enough nickel. ( the base type 304, contains ± 18% chrome and 10% nickel roughly) The nickel gives the material an austenitic structure and it loses it magnetic abilities if it is fully done right.

I just held a magnet against mine. They are magnetic. Witch generally means it isn't a 300 series.

Given the function of the thing it would be a fairly logical guess they use a 420 or 431 type or similar... ( Martensitic : wear resistant and not overly sensitive to atmospheric pollutants and saltwater for short periods) These types generally have a nickel content of 1-3%( 431) or even no nickel at all(420) and naturally form a chrome-oxide coating... I think the amount of nickel you'd be in contact with would be fairly minimal.

As a disclaimer : i have no idea how severe a nickel-allergy reaction can be... my father also has had problems with chrome plated watches so there could be more evil doers for you...

Another disclaimer : there are a few thousands of specific kinds of stainless steel, i am doing some educated guesswork here. I haven't analysed the things although i could determine a general composition at work if wanted.
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Interesting... My pin is magnetic but just slightly. I have a really strong magnet here at my desk and it barely pulls on the pin.

The other metal that is causing the blisters is 10k gold which wouldn't have much nickel either I think.

From what I'm reading, once you are sensitized, jewelry with small amounts of it can set you off.

~Cindy~
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10 karat gold is roughly 40% gold with 60% other metals to create a more wear resistant item...

Usually silver, copper, nickel and tin if i am correct... i believe they aren't obliged to mention the exact composition.

Interesting to know : Nickel is in the same metal group as platinum, so it could biochemically give a similar irritation.

Although i strongly doubt they would use platinum in closing pins and if it was in your jewelry they would make a big deal out of it so you'd probably know..

Could really be worth finding those specifics out... Good luck!
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10 karat gold is roughly 40% gold with 60% other metals to create a more wear resistant item...

Usually silver, copper, nickel and tin if i am correct... i believe they aren't obliged to mention the exact composition.

Interesting to know : Nickel is in the same metal group as platinum, so it could biochemically give a similar irritation.

Although i strongly doubt they would use platinum in closing pins and if it was in your jewelry they would make a big deal out of it so you'd probably know..

Could really be worth finding those specifics out... Good luck!

My rings are yellow 10k gold (for wear resistance) and a platinum diamond setting(to make the diamond look sparkly and for strength) . The platinum does touch my finger.
Would there be more than one type of curved closing pin material? Would that be a TSOed part that would have to be made of something specific? I guess not seeing as it is not part of the reserve system.

~Cindy~
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If you want to keep wearing your closing pin as jewelry, just have it coated. You could get it professionally done, but I'm not sure where. Or just take the cheaper route & coat it in clear nail polish or a clear varnish from a craft store.

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I doubt the specific material grade would void any TSO'd system as long as it is a proper choice that doesn't corrode, break, bend or whatever in "normal" use conditions. I guess a decent quality control wil cover this.

I have put my old closing pin necklace in my wallet. If i get a chance at work i will try to get a general composition of mine for you.

But it is not unlikely different producers use different alloys.

On the other hand it is also quite likely one producer makes these things and because there isn't a really huge market for it or it is patented all gear manufacturers end up buying the same thing from one supplier and will last several months/years with one production batch.

Maybe some riggers or manufacturers can shine some light on this.
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Hi, I got around to determine the composition of my closing pin.

Most notable :
16% Chrome
4% Nickel
4% Copper
0.5% Silicium and about the same amount of Manganese

If you want to know more of this material try a search for "17-4 PH".
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I doubt the specific material grade would void any TSO'd system as long as it is a proper choice that doesn't corrode, break, bend or whatever in "normal" use conditions. I guess a decent quality control wil cover this.




The curved pin is for closing the main container, has nothing to do with TSO.

Sparky
My idea of a fair fight is clubbing baby seals

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Two companies make the bulk of the reserve ripcords pins sold in the USA: Capewell and JCO Metals.
JCO is a subsidiary of a Jump Shack/Parachute Labs/etc/ located in the same building as Jump Shack in DeLand, Florida.
If you want an earful about parachute hardware metalurgy, get John Sherman on the forum.

However, curved (number 6) pins used on Sigma reserves have gone through at least three different iterations. The first batch were cold-stamped from sheet stainless steel, but tended to bend. The second batch of Sigma reserve pins were cold-stamped from thicker stainless steel, while the third batch were hot-forged.
Hot-forging requires more expensive tools, but produces parts 15 percent stronger - for the same weight.

The Aerolite A(?) subsidiary of Square One also cold-stamps various parachute pins out of sheet stainless steel. See page 180 of the 2009 Square One catalog.

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Hi Rob,

Quote

If you want an earful about parachute(s), get with John Sherman on the TSO committee.



I spent 20 yrs with John on that committee.

I have a lot of respect for John Sherman.

:P

Put that does still not answer my question regarding any TSO certification regarding straight or curved pins.

JerryBaumchen

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However, curved (number 6) pins used on Sigma reserves have gone through at least three different iterations. The first batch were cold-stamped from sheet stainless steel, but tended to bend. The second batch of Sigma reserve pins were cold-stamped from thicker stainless steel, while the third batch were hot-forged.
Hot-forging requires more expensive tools, but produces parts 15 percent stronger - for the same weight.



What about the wire version that was bent and brazed?
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
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"
Quote

...



What about the wire version that was bent and brazed?

"

..........................................................................

We try to forget about the wire version.

If any of your clients still have wire pins(GASP!!! SHOCK !!! HORROR!!! ???), give them the sales pitch on Sigma pins.

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The only tandem gear I have any interest in packing is my personal Micro Sigma, and it has the newest version of the pin.

I don't think I'd even entertain the thought of packing one of the brazed wire 6 pins on a rig.
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

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Quote

Yes, the straight pin and the rest of the reserve ripcord assembly are all TSO'd parts.

Ken



I think he may have been talking about the straight pin used in a pull out system. It is not TSO’d.

Sparky

http://i397.photobucket.com/albums/pp55/mjosparky/Skydiving/IMG-1.jpg




I did not even know there was two kinds of straight pins.
I know you can have a straight pin on the main setup as your picture but I did not know it was a "different" pin.

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