Best twin tank for not tall guy ?

[rx7diver]

... Choice would be between twin 10L vs twin 12L, but this is not really about volume or weight but height tank, around 10cm différences between two . I'm 1m71/72 (5ft7-8?) ...

I don't think it was mentioned upthread, but life can be a bit simpler if you and your tech buddy (buddies) are all using the same types of cylinders for your doubles. So, everyone in double 232 Br 12's (for example), or everyone in double 10's, etc.

FWIW,
rx7diver

 

[sharko108]

I think you're missing the point. That's your max time with no leeway. Problems are like pregnancies, they never happen when it's convenient. You can guarantee Monsieur Murphy will come knocking at 31 minutes and 58 seconds and at that point you are going up. Your gas planning now has no scope for returning to the ascent line and probably no spare gas for shooting a bag until you reach your first gas switch. Personally, if I was planning this dive, I'd be looking more at maybe 25 min bottom time. Meanwhile everyone with 12's is doing a longer dive with more of a reserve.



Yes, part of it is finding comfort. But part of it is also getting used to a bit of discomfort too. Not many people enjoy deco but if you want to do certain dives then you have to eat a **** sandwich. Diving is rarely perfect.

It's your choice. You have to prioritise what you think is most important to you. Everyone is different. For me, 10's for that kind of diving is a compromise too far.



So are you planning 50-60m dives on air? If so then I'd want to give myself as much reserve as possible. You really don't want to be dealing with stress, narcosis, dense gas and potentially being a bit low on air as well all at the same time if you are faced with an emergency. That is a disaster waiting to happen.



Faber do/did short 10's, shorter than the Euro 10's are. I don't know how available they are now. They were popular in the UK at one point (I don't know why) but they really are awful to dive with. I doubt many people buy them now.

The problem with short cylinders is your arse needs to be lower than the base of the cylinders to get your harness on. This is really awkward on a boat bench and really hard on your back when you try to actually get up into a sitting position. Like you will **** your back up eventually with them.

Plus they sit higher up your back in the water. I found it put a lot of strain on my lower back when I used them. I've never had that with longer cylinders, even with 20's.

Oh but i didn't say i would do 32min at 60m i just answered to the previous message! If i had to plan 60m with D10, it would be more like 17min bottom. In case of failed deco tani i could do it with bottom gaz and end up with 40b left (but this is an emergency case) + i could still take my buddy deco when i'll have finish his own deco (+ could still shoot yellow dsmb in last need). But tell me if this is a wrong way to plan with one deco please, open to suggestion.

I can't wait on sunday to finally have a second thought about it lol . Maybe in fact it will just be fine this time with D12 so end of the question! Hopefully
Yes air with deco , Nx50 usually (did it with some 70-80% too) as in case of emergency you can take it sooner .
So for you, D10 for that kind of dives is compromise because of lack of gaz reserve in case of multiple emergencies? I understand

Ok i see what you mean to put harness on lol. I remember this summer doing that little half squat position while putting it on with 15L tank (which is longer in fact !)

I just checked back at this photo and yes in fact i thought the 15L was smaller next to the 12L long . Because i've no problem with single 15L length (maybe because it's only one tank centered on the back and not 2x1 resting on each arse?)
I don't know if you've seen the pic i put before but it seems that the D10 on my buddy doesn't seem that short? Or just an illusion lol

 

[sharko108]

This is where my experience of twin diving probably differs from yours!

When I'm boat diving its normal to sit on a bench or rib tube to kit up. This can take me a while to achieve. Once strapped into my 12s I'm comfortable. Add on a stage or bailout and comfort reduces. Then wait for the boat to get into position...

Again, just my own experience of UK drysuit diving. If you are able to make your choice of equipment work for you then it's all good.

Actually you are right it's not really less than a minute as you usually take some Time before to gear up , harness first , long hose management , clip on deco etc.. and the Time for the boat to finish its manoeuvre, so yes now i remember that situation this summer

I don't think it was mentioned upthread, but life can be a bit simpler if you and your tech buddy (buddies) are all using the same types of cylinders for your doubles. So, everyone in double 232 Br 12's (for example), or everyone in double 10's, etc.

FWIW,
rx7diver

Yes probably one of biggest issue. It can already be difficult to find tec dive buddies ..