e7-100's as doubles, or move up to 120's?

[mossym]

Hi all
I ordered an e7-100 from my LDS, with a view to getting another soon and doubling them up. However, now iafter reading herei'm worried that these will be too short for me, i'm 6ft1, and i'm wondering if i'd be better off with e7-120's i can probably still change the order, anyone got any opinions?

 

[Uncle Pug]

I've no experience with E7-100s or E7-120s doubled so take this for what it is worth.

I have double lp72s and double lp104s which are quite different in dimensional size (as well as capacity.) I'm 5'10" and don't have a trim issue with either size.

My advice would be to get the larger tank since you are big enough to handle it easily and it doesn't hurt to have the extra capacity. Trim isn't the issue.

 

[hex92]

I have 120s and they are the perfect size for me (6'4"). The 100s are essentially the same size as an aluminum 80. You have used those... So you can make an informed decision.
I always found them too short.

I bought 120s with the left and right posts already on them so I could double them in the future. I haven't decided when that will occur.

 

[mossym]

yeah, what i read is that i may have to mount the e7's farther down my back to trim correctly, so i might not be able to reach the valve...have never dove doubles, but these are an investment for the future..

 

[Uncle Pug]

The upper bands on all of my doubles are set as high on the cylinder as they will go (making the tank as low in the bands as they will go.)

 

[mossym]

Thanks Guys, think i'll call the store and see if i can swap..

 

[ScubaDadMiami]

I have E-7 120s doubled up. I think they are pretty sweet altogether.

I am only about 5'9". Just to give you some kind of idea, they tend to hang to about half way from my arse to my knees.

 

[Doc Intrepid]

Thanks Guys, think i'll call the store and see if i can swap..

"Do not purchase expensive steel tanks that I have not tried out first before dropping $700 or more on". Lots of opportunities exist to try out sets of doubles first. If the guy wants to sell them to you badly enough, he'll help you find a customer willing to let you give them a try. The trick to reducing scuba stress is to learn lessons using OPM - "other people's money". It beats hell out of trying to exchange one set of tanks for another set that would work better for you...

 

[Warren_L]

I'm pretty similar to ScubaDadMiami ... 5'9" with the E7-120s doubled up. The bands are about as high as they can go, and I don't have any problems with banging into them with my legs in the least. I still seem to go head down a little when I stop. Perhaps that's normal, but not quite sure. Maybe some turtle fins might help....

 

[mweitz]

Hey mossym,

I have a pair of them (as single tanks) and would be happy to let you check them out. I live fairly close to you.

They are LONG. I have a buddy who is your height who keeps bugging me to swap my 120's with his 100's. I may take him up on it.

In any case, they are a bit long for me and I have a bit of trouble keeping trim. They tend to push down on my head.

Also, remember that they will be pretty negative when full, they are -10.5 each, plus the manifold, plus the bands. Maybe -24 or -25# when you are finished? Double 120's will weigh around 100# out of the water, Double 100's will weigh around 85#. E7-100's are a LOT of air doubled up (well, 200# to be exact). What is your SAC, who do you dive with that uses doubles, what do they dive, what exactly do you want to do with em? Remember that you determine your dive plan based on the guy with the smallest tanks. If you have 120's and your regularly dive with someone with double 80's or double 100's you base your turn on their tanks.

You can also get rid of 100's a lot easier than 120's. If you don't believe me see how long it takes you to find E7-120's in a store and how long it takes to find E7-100's.

You may want to get the 120's as singles tanks then get a pair of 100's for doubles when the time comes

Mark