Hello, I see DGX is now stocking AL72's made by Metal Impact. I'm not familiar with this company and am wondering if anyone has any experience with these and how they compare to Hy-Mark's (seems to be preferred AL72 on here) or Catalina's (I'm not sure if Luxfer makes or ever made of AL72)?
I'm also wondering why AL72's aren't more popular for deco bottles. It seems to be an optimum size for a 50% bottle by my calculations. For a tech dive that can reasonably be done with just one deco bottle (i.e., about 30 minutes of deco), the average depth from 70 to surface is ~2 ata, SAC rate assumption of .75 cuft/min (I know this is much higher than mine and most people'd SAC for deco, but works for a conservative estimate), ends up requiring about 45 cu ft. Multiple that by 1.5 and you need about 68 cu ft of 50%. But most people I see on charters here in S. Fl are using 80's (myself included) or 40's (too small unless doing short deco or also carrying O2). Is it just because of availability issues or is there another reason to prefer an 80 over a 72 for the 70 ft bottle?
I'm also wondering why AL72's aren't more popular for deco bottles. It seems to be an optimum size for a 50% bottle by my calculations. For a tech dive that can reasonably be done with just one deco bottle (i.e., about 30 minutes of deco), the average depth from 70 to surface is ~2 ata, SAC rate assumption of .75 cuft/min (I know this is much higher than mine and most people'd SAC for deco, but works for a conservative estimate), ends up requiring about 45 cu ft. Multiple that by 1.5 and you need about 68 cu ft of 50%. But most people I see on charters here in S. Fl are using 80's (myself included) or 40's (too small unless doing short deco or also carrying O2). Is it just because of availability issues or is there another reason to prefer an 80 over a 72 for the 70 ft bottle?
