Steel vs AL for rentals?

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edoralive

edoralive

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If you don't NEED the extra air, I'd just stick a few pounds in my pockets and go with it. If the majority of your dives have been 40 foot, pretty fish, dives and these will be substantially deeper, in current, or anything froggy, extra air is always good. If the dive op lets you dive your tank and says be on the line with your buddy 1 hour after splashing, it might be worth it the first day so you don't cut a dive short.

I'll be diving in a drysuit (or call it a sweatsuit) in 80 degree, zero visibility, water with the temps 100+ this weekend....I'm jealous. sooooooooooooooooo jealous.......

Safe dives!!
Jay

Thanks man! I was diving Lake Superior last weekend in a drysuit in 95 degree air temp and 39 degree water temp with 20 ft visibility! Good stuff!

I think these dives are well within the range of what I've done previously, except I'm told they're pretty square, which I only really have experience with on the deep dives in Key Largo.
 

tbone1004

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Appreciate this. Yeah, looking at the website it looks like 90' is the deepest of the dives I would be doing. My computer says 27 minutes at 90' for NDL on EAN32. When diving deep in Key Largo, NDL was always the gate, not air supply, so it seems that unless I want more of a gas buffer, the larger steel wouldn't lead to longer dives, per se.

quick rock bottom calculation.
27mins @90ft with an "average" sac of 0.6cfm. 0.6cfm*3.7ata*27mins=60cf consumed. Ascent from 90ft is 4 minutes @avg of 2ata=5cf for ascent, and safety stop of 5 minutes at 15ft=4cf for safety stop. Grand total call it 70cf. 3000-70*3000/77.4=286psi when you get back on the boat.
It does not account for rock bottom, does not get you back on the boat with 500 or 700 or whatever nonsense they require, but the 27mins NDL is also only going to be your first dive and the rest will be shorter, and you won't be hugging the bottom at 90ft for the entire dive which brings your reserve back.

I think you'll be bumping into NDL's to the point that the 100's or 120's may buy you an extra 3-5 minutes on the bottom, but that to me isn't worth $10/dive
 

wnissen

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That doesn't seem like a good value. A steel HP100 is $15 flat to rent around here. Plus you're only carrying 8 lbs so it's not like you would be cutting your weight down a ton.
 

Julius SCHMIDT

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After a steel on your back, well, you won't go back
 

lowwall

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I'm heading to Jupiter in September for two days of diving with Jupiter Dive Center, and see that they offer Nitrox AL80s and Steel 100 and 120s. I've only ever gone with the AL80s, but am curious if it would be worthwhile to check out the larger steel cylinders for this trip.

The 100s are a $10 premium over the AL80s.
The 120s are a $16 premium over the AL80s.
I am not a gas hog.

I'm usually carrying 8lbs in addition to my BPW and an AL80 when I dive without a wetsuit, if that is meaningful.

Thanks!
I'd get the 100s. For $40 you get to try something new, get some weight off your belt and maybe get a few more minutes of dive time. It's also fun to be able to do some extra finning without having to worry about gas consumption.

I wouldn't bother with the 120s. They are kind of ungainly in the water and it doesn't sound like you will be able to use the extra gas.
 

Squirm88

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Solid point about instabuddy. Looks like 2 of the dives I'm booked for are nitrox-required dives, the rest are just nitrox-encouraged. I'll be arriving to boat alone, so instabuddy it is.

Based off my dive long and my computer, it looks like NDL will be the gate, not air consumption.

Really looking forward to the Jupiter trip. The folks in Key Largo were raving about Jupiter... seems the seagrass is always greener somewhere else.

JDC is pretty lax on the dive buddy requirements. There's a guide included on each dive. I usually just follow them when diving on their boats solo. I would definitely do the steel 100. They bank 36% at their shop. So your rental tanks will be filled with 36%.
 

tbone1004

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if they're banking EAN36 then the 100's may actually be worth it. That puts your EAD up at 66ft from 90 and you should have way more than 27mins of NDL.

I honestly have no idea how to get NDL's out of my computers and DecoPlanner doesn't acknowledge NDL so I'm not going to figure out what it actually is, but it should be seomwhere around 45-60minutes depending on your gradient factors.
 

rick00001967

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i would much rather stick with the allum 80 an add a 19cf pony. but that's me.

not to mention if you switch to a steel 100 you probably won't need much lead, if any. maybe only a couple of pounds. so if you are used to diving with some ditchable lead, this may not be something you are comfortable with.
 
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