Why is an AL80 not 80?

[Greendiver]

So how did it come to be that the actual capacity of an AL80 is really 77 even though the neck is stamped 80?

 

[knotical]

For the same reason a 32 inch TV isn't 32 inches ?

 

[scubafanatic]

I'd heard the tank stamper guy misplaced his "77" stamp so he decided to use the closest alternate stamp he had available, hence the "80".....

 

[Greendiver]

Kinda what I've been thinking, no real reason at all.

Makes me kick myself for passing on all of the 72's to buy a pair of new AL80's. For the money with a typical short fill I'd have been further ahead with the underrated 72!

 

[redacted]

77.4 to one significant digit is 80.

Or, as they said on Seinfeld, "You do know about shrinkage?"

 

[Greendiver]

77.4 to one significant digit is 80.

Or, as they said on Seinfeld, "You do know about shrinkage?"

Shrinkage? In this weather and water, ya!:shocked2:

 

[diver 85]

close enuff for government work......

 

[Greendiver]

...and I've had plenty of great dives on my 80s...er...77s!

 

[captain]

Advertising, common practice to round up or down, which ever paints the product in the best light. Common in boat advertising, a 29'3" boat becomes 30'

 

[Scared Silly]

Marketing ... so that folks would think they were getting 10% more than a 72.

Actually, I think it went some like this nonsense: The size and weight of the billet of AL was some easy measure, when formed the cylinder held 77 cuft of gas, then as I said marketing got a hold of it and said call it an 80.