Why not bronze?

[grouchyturtle]

The most common metals for marine applications seem to be stainless steel, aluminum, and bronze (especially for below the water line) Perfect example, bronze thru-hulls. The stuff just seems to last forever. Brass on the other hand is less common, because it seems to rust very quickly in a marine environment.

So, why is it that with dive gear you see stainless and aluminum, but the other common metal used at least for hardware is brass, and bronze isn't really used?

Maybe comparing dive gear to boats is apples to oranges, but really the only major difference is dive gear is always going to be submerged, but only for short periods, whereas on a boat, it's either not going to be submerged at all...or submerged permanently except during haul outs.

 

[cmburch]

Wiki Bronze

It looks like it is harder and more corrosion resistent. Perhaps it may be more costly due to higher copper content. Interesting post.

 

[grouchyturtle]

...and what am I looking for?

Is it because it's a softer metal? I already knew that.

Yet not so soft that it's not still used for marine hardware.
Also softer than steel, but is it softer then brass or aluminum.

 

[Mr Carcharodon]

I think this is an artifact of the machining technology that was available up into the early 1990's. Which was several generations into regulator design. It was easy to make machined parts in brass and chrome plate them for corrosion resistance. If the chrome plating is good, which is a big if, they are pretty durable. Now we have better cutting tools and can make titanium parts pretty readily with only a marginal difference in cost. Personally I think it makes sense to make all the parts with threads out of titanium since the radii in those parts typically plate poorly. Of course the marginal difference in cost is only for the manufacturer. The consumer usually pays a significant premium.

 

[scubafanatic]

...well, the Bronze Age ended several thousand years ago, be modern and embrace the Plastic Age !

 

[grouchyturtle]

Yeah even just a titanium screw costs 100x as much as bronze or stainless.

scubafanatic - plastic regulators? plastic bolt snaps? plastic D-rings? plastic valves?

 

[cmburch]

Well harder, more corrosion resistent than brass. More costly? Harder to tool?

 

[Walter]

Brass rusts?

 

[grouchyturtle]

Brass rusts?

I know, I know, in scuba applications, like bolt snaps where it's getting limited exposure it doesn't.

But on a boat...HELL YEAH! And especially never used for anything below the waterline.

 

[scubafanatic]

Yeah even just a titanium screw costs 100x as much as bronze or stainless.

scubafanatic - plastic regulators? plastic bolt snaps? plastic D-rings? plastic valves?

.....it was meant as a joke, but now that you mention it, all the things you mention ARE commonly manufacturered in plastic for scuba gear. Plastic 2nd stages have become the norm, Apeks recently came out with plastic 1st-stages.....recreational BC's are chock full of plastic D-rings (especially the new lite-weight 'travel' BC category).....plastic bolt snaps are available......and plastic valves are widespread in dry-suits abd BC bladders/wings, for example.....come to think of it, I've never heard of a metal BC dump valve, for example.