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PVD on stainless steel?

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PVD (Physical vapor deposition) is a metal coating technique used in the watch and tool industries. It doesn't change the structural capabilities of the material except its color, friction (it reduces) and wear (improves).

Question is, if I apply PVD to the metal parts of my rig, will I have problems when I send it out for packing? Will riggers refuse to do it? Do I need approval from the factory?
Una volta che avrete imparato a Volare, camminerete sulla terra guardando il cielo perchè è là che siete stati ed è là che vorrete tornare.

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the buckles on your chest and leg straps depend on friction to function properly. Reducing friction could mean athose things not working as designed.
"Where troubles melt like lemon drops, away above the chimney tops, that's where you'll find me" Dorothy

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Which parts?

How are you planning on coating them? By this, I mean do you plan on removing them, coating them and replacing or coating while in place?

Personally, I can't see it being done without voiding the TSO.

Kind of like recoloring or painting a container, if someone brought me a rig with this sort of modification, if they didn't have some sort of approval, I'd refuse to pack it.
But that's just me.
"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

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If you add a coating you will change the dimensions of the parts. The inside diameter of rings will become smaller with unknown consequences. I would not pack it. But the ultimate authority is the manufacturer. Check with them.

I am curious about how you apply this coating. Are you planning to take the harness apart to remove the hardware and then sew it together again?

Ken
Always remember the brave children who died defending your right to bear arms. Freedom is not free.

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Aside from how to do it without removing from harness, the reduction in friction could kill you.

When hardware went from cadmium plated to stainless it had to be redesigned. The 'teeth' on the stainless leg strap friction adapter bit too hard, didn't allow the hardware to slip a little and resulted in damage and harder perceived openings. The cadmium plated dulled the teeth somewhat. The stainless had to be redesigned with less aggressive teeth. We already have problems with hardware slipping. Type 12 webbing has a thickness spec of 0.08 to 0.120 inches. It used to run on the thick side. Depending on the dying process it's now running on the thin side and aiding in hardware slipping.

(Before John chimes in yes most of the hardware was designed for type 13 webbing and Parachute Labs uses type 13. But most of the world has been happy with type 12 in the hardware for decades.)

You do NOT want to do anything that will change the friction of the hardware. How will it kill you? It could cause the legstraps to go to the stops on opening and break your neck with the chest strap. Just one scenario.

Don't mess with a design you didn't create and the hardware design is part of it.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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Not to be nit picky but I think you mean type 7 and type 8. 12 is some times used as a buffer strip and contacts one side of the hardware. I'm not sure if it's a variation in the thickness that has caused more slipping. There is a lot of variation in the resin coating of condition R webbing and I think it may be a product of the difference if stiffness rather then actual thickness.

I actually wouldn't mind seeing other plating options explored. There are some really cool technologies that have come around that we are just ignoring. I think it would be a really cool project. Now having said that I think it's a project that should be taken on by some of they foundries that make the hard ware. I don't think takeing a set of condition three down to a shop and having some thing exotic done and testing it by sewing it into your harness is the way to do it.

Why explore these things? Some of the things we are doing right now are or potentially can be problematic. Example. We were really pushing the limits on a release and we started doing some destructive testing. We were breaking the RW-9, big ass heavy three ring, at around 16,000 pounds. Then one of them broke at 7,000 lb. What the fuck. I was talking to the guys from Borden about it and they got all excited. Although this peace was made by Forge Craft they make the same peace of hard ware. When I showed it to them they were able to identify obvious signs of hydrogen embritalment. The point is that this is some thing that made it through the QC process of a major manufacturer. You can have some real issues with this stuff. We need some better, less invasive, options.

Lee
Lee
lee@velocitysportswear.com
www.velocitysportswear.com

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The only way would be to get ahold of the parts before the manufacturer assemblies it or get a rigger to undo the webbing. You can't put fabric on the PVD chamber.

Now, reading the other posts here I started thinking about TSO. Would a change like that require a new TSO approval?
Una volta che avrete imparato a Volare, camminerete sulla terra guardando il cielo perchè è là che siete stati ed è là che vorrete tornare.

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PVD is not like anodizing. While anodizing will add around 2 microns, decorative PVD won't add another 300 nanometers. The tolerances of the parachute metal parts are at least one order of magnitude larger than that.
Una volta che avrete imparato a Volare, camminerete sulla terra guardando il cielo perchè è là che siete stati ed è là che vorrete tornare.

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The metal parts you consider are the three rings (base ring + risers) and the articulation rings. You don't want reduced friction reserve handle or friction adapters.

Want to know if it's a good idea?

Communicate with and identify a mfgr willing to experiment and provide some PVD'd hardware. Bring your checkbook.

Best case? You contribute to the sport. Worst case? You contribute to the sport (negative results are still results!)

Remember $ is the lifeblood of R&D.

Cheers

.02
"Even in a world where perfection is unattainable, there's still a difference between excellence and mediocrity." Gary73

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I knew 12 wasn't right when I wrote it but too lazy to look it up. Type 7 common use for harnesses. Type 13 (7000lb) is what it was designed for and Sherman uses.

The difference in thickness comes from the dying process. I'm going to get it wrong but here's the laymans version as discovered during meetings on slipping led by Ted Strong at PIA business meetings. Large lots (like black) are dying continuously under tension. Don't remember the name of the process. Smaller lots (like pink) are dyed in a batch process that allows the webbing to swell more. Both are in spec but newer continuous process produces thinner webbing. And yes the resin coating has varied just as much over the years and contributes probably as much.

Booth tells the story about the first stainless hardware.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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