|
Post by technidiver on Jan 2, 2019 18:37:54 GMT -8
Da-Zam, TD! One steel 72 is more than enough for me when walking up and back from the beach! They're neutral in the water, and I still need 30 lbs on the weightbelt. I thought about double 72s once, then I woke up! You youngsters can hack it, I 'spose. Eh, I'm lucky I guess due to my age and height (not for wetsuits though, that's a different story!) I was reading online the different weights for tanks and surprisingly a steel tank weighs less than an aluminum tank. I couldn't believe it but I checked again. TD So Twin Alu 80s are out of the question as well as 90s and 100s!
|
|
|
Post by technidiver on Jan 2, 2019 18:40:56 GMT -8
I think the question to ask is what amount of air do you need. The double steel 80s would work, and it looks like the bands are the same as for an AL80. But weight is heavier than either the twin 72s or the twin 50s. Usually twin 72s, twin 80s and twin 100s are used in tech diving to do deep, decompression dives. I used for years twin 50s, and they have very nice buoyancy characteristics. I retired them about three years ago, simply because of the sustained pressure cracking issues that this alloy of AL has. I still have those cylinders, but they are under zero pressure, and have been replaced with my twin 58 cubic feet, 1800 psig tanks (which have a buoyancy characteristic that necessitates six pounds of weight to be the same as my twin AL 50s). Since I'm not currently diving these tanks, and have replaced them, I would consider selling them. They will need both a hydro and an eddie current test. I just picked up a set of twin AL 40s, which are really slim and nice in the water. My LDS has a set of these tanks which they are selling for pretty cheap too. John John, I would be interested in those tanks sometime but there's two things that I'm concerned about. 1. You mentioned the alloy is finicky and has sustained pressure cracking issues. This might not be an issue, but where I live they will not touch cylinders that even look bad. I've had friends of mine who's Alu 80s were a bit rusty on the outside and were denied. Might've been because of the age. 2. What type of bands would this tank take? I've read that modern 50s have 6.9 inch diameters and the only place I know that sells bands that fit is NESS. TD
|
|
|
Post by technidiver on Jan 2, 2019 18:42:40 GMT -8
I have a set of 1969 US Divers twin 72's that I have yet to dive. Just never got around to hauling them out of the basement...LOL. Plus I am just so content and used to a steel 72 with the shallow "Soul Diving" I love diving. But, I still want to dive doubles this Summer. I'd love to have a set of 38, 42, or 50's someday though. Mark Mark, when you get your doubles up and ready, you should try out your Deepstar Regulator as well! That 1969 twin 72 set sounds sweet! Keep us all updated about it! TD
|
|
|
Post by SeaRat on Jan 2, 2019 23:08:33 GMT -8
I think the question to ask is what amount of air do you need. The double steel 80s would work, and it looks like the bands are the same as for an AL80. But weight is heavier than either the twin 72s or the twin 50s. Usually twin 72s, twin 80s and twin 100s are used in tech diving to do deep, decompression dives. I used for years twin 50s, and they have very nice buoyancy characteristics. I retired them about three years ago, simply because of the sustained pressure cracking issues that this alloy of AL has. I still have those cylinders, but they are under zero pressure, and have been replaced with my twin 58 cubic feet, 1800 psig tanks (which have a buoyancy characteristic that necessitates six pounds of weight to be the same as my twin AL 50s). Since I'm not currently diving these tanks, and have replaced them, I would consider selling them. They will need both a hydro and an eddie current test. I just picked up a set of twin AL 40s, which are really slim and nice in the water. My LDS has a set of these tanks which they are selling for pretty cheap too. John John, I would be interested in those tanks sometime but there's two things that I'm concerned about. 1. You mentioned the alloy is finicky and has sustained pressure cracking issues. This might not be an issue, but where I live they will not touch cylinders that even look bad. I've had friends of mine who's Alu 80s were a bit rusty on the outside and were denied. Might've been because of the age. 2. What type of bands would this tank take? I've read that modern 50s have 6.9 inch diameters and the only place I know that sells bands that fit is NESS. TD TD, I have decided not to sell my twin AL 50s. I am also moving the bottom two posts to a new thread in the "Buy, Sell and Trade" forum here. John
|
|