Quality Plastic Buckles? Want to Switch from SS to Something Lightweight

[eelnoraa]

Gee, I thought I had made a wisecrack when I mentioned something along the lines of "then why not titanium?" Sure, I suppose a relatively thin Ti backplate would be lighter than an equivalently rigid and thicker Al one. But with the difficulty of bending and machining the stuff factored into the retail price, I think it would be way less economical than an Al one. To me, part of the beauty of the BP/W configuration as opposed to a jacket-style BC is that it can be economical. A metal plate--it doesn't get cheaper than that ... unless you start making them out of exotic metals. If you are such a spendthrift gearhead that you'd buy a titanium plate with the idea of using it for airline travel, you probably aren't the type who would balk at the airline's fee for a second bag or could not qualify for the airline's credit card that gets you "free second checked bag."

Me wasn't all that serious either. It is a very stressful life if everything needs to be so precise and serious.

My only experience working with Ti was a home project of making a selfie pole with Ti. It was for fun because I have some Ti tube available. What I found was Ti isn't very good when it is very thin (in diameter). In particular, they are NOT very stiff at all. While Ti may be 2-3x the "strength" to ratio of SS, it is about 1:1 in terms of stiffness. In making a selfie pole, stiffness is important, having a Ti tube needs to be thicker than SS. I ended up with the same weight or maybe even slightly heavier.

BTW, my selfie pole was intended for a DSLR. It wasn't a go at all. The tube is too thick in diameter than I like in order to take the weight. and I had no control on the wall thickness of the tube, so can't experiment there.

 

[stuartv]

Wrong. What difference does it make if the plate flexes a little? It's only going to do so out of the water anyway.

What alloy of Ti would you be using that can handle repeated flexing without cracking or getting a permanent bend eventually?

Wrong again. Ti is about 1/2 the density of Stainless Steel. To be lighter you need less than 1/2 the thickness. Open a Steel manual and learn what happens when you decrease the distance from the neutral axis..........

With a ~18 gauge Ti plate the risk of permanent bend is high.

18 gauge (~.049 thick vs 11 gauge ~.118 thick) is going to do bad things to the webbing at the harness slots.

Ti plates are silly.

Tobin

Wrong again. A Ti plate of the same thickness will weigh about half what the SS plate weighs. To be lighter, you just need less than DOUBLE the thickness (roughly).

---------- Post added September 16th, 2015 at 03:55 PM ----------

I am with NetDoc. The importance is never the strength for backplate, otherwise, Kydex will never exist. Soft fabric plate will never exist either.

The strength is important for metal plates, which is what we were talking about. Metal plates that flex frequently are going to get metal fatigue and crack before long (generally speaking).

 

[cool_hardware52]

What alloy of Ti would you be using that can handle repeated flexing without cracking or getting a permanent bend eventually?

Ti plates are silly. Your point was plate flex was a problem. It's not. Our Kydex plates flex quite a bit.

Wrong again. A Ti plate of the same thickness will weigh about half what the SS plate weighs. To be lighter, you just need less than DOUBLE the thickness (roughly).

Forgive me I meant aluminum. Ti is ~285 lbs / cuft and al is ~160. You would need a ti plate to be about 1/2 the thickness of the current 1/8" thick aluminum plates to have half the mass.

The strength is important for metal plates, which is what we were talking about. Metal plates that flex frequently are going to get metal fatigue and crack before long (generally speaking).

LOL. Do tell. Any idea how many cycles are required for even aluminum to fatigue? at least 10K and probably more like a million at the extremely low stress seen in scuba back plates.

Tobin

 

[annasea]

Regional airlines in Asia are the main culprits in thwarting divers' attempts to take an overweight carry-on bag. Air Asia is reported to weigh carry-on bags in Singapore, which is a popular transit airport to Indonesian destinations. Probably some European carriers like Ryanair, too. In the US it is never an issue.

Air Canada is getting tough on carry-on, too, now. Personally, I don't care too much about the weight; it's the size and quantity that gets me, so I'm overjoyed that AC is now making an effort to enforce their policies re: size and quantity.

 

[Nemrod]

I love my OxyCheq fabric plate! I dived a SS plate previously, then a kydex plate that I'm now trying to sell, and of the 3, the fabric one is by far my favourite. If/when it starts fraying, I can always buy another.

On a vaguely related note, someone once told me that a BP/W would be sorely lacking w/out an STA. And that I'd be pushed face forward at the surface if my wing was inflated. I found neither to be true.

I have no problems with my Oxy plate for the purpose it was designed, minimalist warm water diving with aluminum tanks. Mine has a bunch of dives on it and it is still in fine shape. I do not use an STA as it is built into the Oxy 18 Mach V wing and an 18 pound wing filled to pop hardly has enough lift to push me over.

N

 

[annasea]

Nemrod, are you using one or two cambands with the VDH plate? I'm currently using two with my OxyCheq rig as only one 'seems' like it'd be less stable as I see it as being integral to holding the wing to the fabric plate...

 

[The Chairman]

It needs to be strong enough not to bend or flex when you put on your steel doubles and don your rig, right?

Flex is good when diving, not bad.

To me, one of the advantages of a BP is the weight itself,

Steel tanks are all the weight I need, but the point of this thread was about plastic buckles over steel ones.

What alloy of Ti would you be using that can handle repeated flexing without cracking or getting a permanent bend eventually?

How much flexing could a diver create? Certainly, not enough to cause any problems.

Wrong again.

Read again what Tobin wrote. Until I tried a DSS plate, I always had the harness fray where it passed through plate. DSS (Tobin) was the first to come out with a composite back plate, putting in rubber inserts to protect the webbing. Thick or thin plate, it was an awesome solution. Tobin's point was that having such a thin back plate would result in creating a titanium knife for your webbing. The plate would be strong enough to carry the weight, but the thinness would wreak havoc on the webbing unless you used Tobin's rubber insert solution. Considering the cost of such an item, I agree with Tobin's assessment of using titanium as being silly. It would be as silly as oxygen cleaning your BC.

The strength is important for metal plates, which is what we were talking about. Metal plates that flex frequently are going to get metal fatigue and crack before long (generally speaking).

"Generally speaking", you're completely wrong here. When it comes to plates, steel, aluminum, plastic and/or Kydex, they are all well over-engineered when it comes to strength. I have thousands of dives and I have yet to have the first piece of gear work harden to the point of fatiguing, much less cracking. I can't recall anyone bitching about that here on SB either.

Finally, since you brought it up, we're not talking about plates in this thread: we're talking about buckles.

 

[buddhasummer]

And you can bet your life if this did ever occur a lot bitching would ensue.

 

[RJP]

What alloy of Ti would you be using that can handle repeated flexing without cracking or getting a permanent bend eventually?

He wouldn't be using ANY titanium... that's kind of the point.

Finally, since you brought it up, we're not talking about plates in this thread: we're talking about buckles.

I understand that he calls his keyboard "Threadslayer" - with it he can wade into any discussion and completely derail it with just a few (thousand) keystrokes.

 

[rhwestfall]

Non-Metallic Buckles - generally speaking, materials development has been successful, but the stigma hasn't changed....