HP 100 Steel Tanks - What am I missing?

[cool_hardware52]

Aluminum, 165 lbs / cuft, makes crappy ballast vs Steel, 495 lbs / cuft.

Doesn't matter if it's shaped like a tank or back plate, or blocks on a belt, you want high density materials for ballast.

The higher the density the less the required ballast will weigh *out* of the water. Lead makes pretty good ballast because of it's density ~710 lbs / cu ft.

DU, Silver and Gold would all work well, but have other disadvantages.

Tobin

 

[eelnoraa]

or if it happens on decent you could just grab the anchor line and pull yourself back up.....

There may not be an anchor line, depending on the dive.

Not exactly, remember that properly weighted means floating at eye level with a near-empty tank, so half your head is out of the water. Anyone diving with a single tank that's even close to 18lbs negative at the surface is severely overweighted. But I do agree that the reasoning behind having ditchable weight is to be able to quickly and immediately get positive on the surface. For me that's simply not a problem; I'm not overweighted, I'm a good swimmer, and I can easily doff my rig in an emergency.

It is a bit exergerated, but not too far. At the beginning of the dive, tank is full, so you are overweighted by the gas already. For HP100, that is 8lb. Average human head is 10-12lb. With your weighting, you will support half of it, so 6lb. Total is 14lb negative. How long can one tread water with this under stress?

---------- Post Merged at 11:39 AM ---------- Previous Post was at 11:36 AM ----------

DU, Silver and Gold would all work well, but have other disadvantages.

I have a block of Tungston at home, super heavy for its size. Instead of lead, I can use it as ballast, only it is not in the right shape. Is Tungsten an rare/expansive metal like gold and silver?

 

[cool_hardware52]

I have a block of Tungston at home, super heavy for its size. Instead of lead, I can use it as ballast, only it is not in the right shape. Is Tungsten an rare/expansive metal like gold and silver?

Tungsten is very dense. ~1200 lbs / cuft

Tungsten is not rare, but most of it is mined in China.

Good luck reshaping you hunk of "heavy stone"

Tobin

 

[eelnoraa]

Sorry for the hijack, I couldn't help. I am just so amazed with the piece of Tunsten I have. It is in ball shape, size of a softball. It is some "long last" ball bearing prototype. It doesn't look as good as SS or AL, not to mention gold or silver, just smooth dull and a bit yellowish. It caught my attention when I tried to pick it up. It is soooo heavy. My fingers almost didn't have enough strength to hold it.

Judging from the way it makes contact with other hard material, it is an extremely hard metal, so reshaping it will not be easy, definitely not a home DIY. Feels like it has a high melting point too, so melting and re-moding is probably not possible either.

 

[BEM]

Tungston is not maleable- so having a softball sized weight would be pretty awkward. The melting point is 3,422 deg C., compared to 327 deg C for lead - tough pouring into a weight mold.


But it's not toxic like lead, and would be a great conversation piece before and after dives! About the only place to keep it would be in the groin area (let the jokes begin.)