Width of double 100's

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formernuke

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I just don't log dives
Might be wrong location....

But I'm building a tank drying rack and need to know the max width of double steel 100's.
 
Just to expand a little, standard isolation manifold's center-to-center distance: 215 mm (8.46”) +/- 5 mm (0.2”). Add the OD of one tank and you have the outside width of a doubles set.
+ 2x band thickness ... to be complete. Mine happen to have the rubber isolators on the bands so it is somewhat significant.
 
Mine happen to have the rubber isolators on the bands so it is somewhat significant.

Do your bands have self-draining ribs? I haven't seen rubber isolators for decades because they cause more corrosion than the bands alone. I have often thought of designing a metal stamping that fit between doubles and used nylon webbing for this reason.

A design like this could be produced so the spacing between cylinders very precise so the adjustable with feature of isolation manifolds could be eliminated. Solid forged doubles bars similar to the this one that is still made for the US Navy would be more reliable, except in a isolation valve configuration.

upload_2020-10-7_7-23-48.png


Modern 5-axis CNC machining centers would have no problem making it in one piece.
 
+ 2x band thickness ... to be complete. Mine happen to have the rubber isolators on the bands so it is somewhat significant.

The boots are thicker than the bands. I measured the gap flat part of my band at a little under 2 inches but the part it sits on is longer. I wasn't sure once I assembled them what it would come out to.
 
Do your bands have self-draining ribs? I haven't seen rubber isolators for decades because they cause more corrosion than the bands alone. I have often thought of designing a metal stamping that fit between doubles and used nylon webbing for this reason.

A design like this could be produced so the spacing between cylinders very precise so the adjustable with feature of isolation manifolds could be eliminated. Solid forged doubles bars similar to the this one that is still made for the US Navy would be more reliable, except in a isolation valve configuration.

View attachment 616708

Modern 5-axis CNC machining centers would have no problem making it in one piece.
No drains that I'm aware of. Came with my (used) set of Genesis/PST HP100s. HDG and mostly freshwater diving, so I'm not overly worried for now. Maybe next year I'll have a chance do do some NJ wreck dives or FL training and might be a good idea for me to swap out. I have another set of manifolds and bands to assemble another twinset and those are just bare SS. Same on my tiny dubs.

There is really not much reason that a full isolation set couldn't be made that way if they are already making the single outlet. A bit more difficult to break down and rebuild at VIP/Hydro time I'd imagine, but nothing a strap wrench wouldn't fix.
 
The boots are thicker than the bands. I measured the gap flat part of my band at a little under 2 inches but the part it sits on is longer. I wasn't sure once I assembled them what it would come out to.
Yea, I forgot about the boots. Would make a difference on my 100's with the anti-roll boots but my 50s have those floppy Luxfer sleeve boots that are pretty close to band thickness.
 
There is really not much reason that a full isolation set couldn't be made that way if they are already making the single outlet.

The non-adjustable manifolds often visibly bend as you tighten the bands. AFAIK, that is why most isolation manifolds can adjust the width. I add plastic spacers to ensure that the width is fixed and cylinders are parallel.

full.jpg

A bit obsessive perhaps but it gives me confidence when rough handling is anticipated.
 
The non-adjustable manifolds often visibly bend as you tighten the bands. AFAIK, that is why most isolation manifolds can adjust the width. I add plastic spacers to ensure that the width is fixed and cylinders are parallel.


A bit obsessive perhaps but it gives me confidence when rough handling is anticipated.
Smart! Effective, simple and inexpensive.

I'll have to give that a whirl come VIP time.
 

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