steel vs alum

[nwfellah]

two things;

1. I dive in the northwest and I have heard from several people that steel tanks are better up here (I dive wetsuit). Why?

2. When I go to dive shops, I very rarely get a fill to 3000. Usually it is closer to 2800:wacko:. Is this enough of a difference to complain or am I just being picky? Is there any way to help, um, encourage a fill monkey to kick it up to 3000 without being rude?

 

[dlndavid]

Aluminum tanks are positively buoyant at the end of the dive (near empty). Steels are negatively buoyant at the end. True some shops can't do good high pressure fills, and some even charge more, shop around. I get full HP fills at regular price, so I'm happy.

 

[HowardE]

Additionally to what david said. Most Alum tanks are only rated to 3000 psi. Steel HP tanks can be filled to 3400+ PSI safely, and many places will even fill you to more. Also, a steel 100, which is generally about the same size as an aluminum 80 on the outside... but a steel 100 filled to 3400 psi gives you a lot more gas and bottom time than the al 80.

Also with steel tanks, you'll need less weight in your belt and/or bc whatever your weighting situation is.

 

[LI Diver]

Does anybody know just how much more a steel 100 weighs?

 

[HowardE]

Does anybody know just how much more a steel 100 weighs?

There's no general # for this. Each tank mfg is different.

 

[dlndavid]

Check out this link, it's not my favorite, but can't find that one right now.
http://www.diverdiscount.com/tankspecifications.html

 

[joeabroad]

Does anybody know just how much more a steel 100 weighs?

My new Worthington 100s weigh 34 lbs. empty. I haven't been in the water yet with them (and won't until next summer, alas), but I figure that in terms of removing weight it will be a wash--taking 4 pounds off the belt, but adding 4 pounds to the tank (assuming that the average weight of an aluminum 80 is 30 lbs.) The real plus is the extra air--even if I only fill them to 3000 psi I'll be getting at least 10 percent more air than I would with aluminum 80s.

 

[LI Diver]

David it seems that the hp 100's weigh about 4 lbs more than the al 80's but empty the bouyancy of the steel is 9lbs and the alum is -2.5 so does that mean I can eliminate 11.5 lbs of lead or 4lbs of lead??

 

[LI Diver]

or can I eliminate 6lbs because I'm already 2lbs neg to make up for the alum tank at the end of the dive but since the steel is 9lbs neg empty then I can get rid of that 2lbs and still be 7lbs neg at the end of the dive? Or how about this , do a center of mask test and then just don't add anything to comp for the light tank?

 

[douglasville diver]

I TRAINED AND CERTIFIED WITH AL80'S. FIRST OPEN WATER OWN MY OWN MY INSTRUCTOR WAS NICE ENOUGH TO LOAN ME A COUPLE OF STEEL 104'S, MAN WHAT A DEFFERIENCE,NOT ONLY DID I HAVE MORE BOTTOM TIME BUT THE LEAD I LEFT ON THE BOAT WAS ABOUT 8LBS AND MY END OF DIVE CONTROL ON THE LINE WAS WAY MORE EASY!
TO BAD HE DID'NT LOAN ME SOMTHING I COULD BUY !
ONE WEB SIGHT I PICKED UP FROM HERE IS
http://www.huronscuba.com/equipment/scubaCylinderSpecification.html
SORRY I DON'T KNOW HOW TO SET UP A LINK JUST YET , BUT THIS IS A GREAT PLACE TO GET A TON OF CYLINDER SPEC.