My journey into tech
- Thread starter Marie13
- Start date
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OP
Thanks! Another pool session tomorrow (shop has these once a month in winter), and March pool session will include some time with SM instructor. If things go well, I might even try SM on a Lake Michigan charter over the summer.
OP
Question on tank sizes for AN/DP (probably two years down the road) that popped up. I realize my HP80s are an odd size for tech and would probably complicate gas matching. However, drivers do use AL80s doubled up, so I guess my question isn’t totally crazy. If I’d be able to use my HP80s for AN/DP without having to get HP100s, that would be lovely, not having to shell out for other tanks. I do have two sets.
And, yes, I have asked my instructor.
And, yes, I have asked my instructor.
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CptTightPants21
Contributor
160cuft is enough for a short single deco dive. You'll be looking at ~80-100cuft in min gas, and have ~60-80cuft left for the dive.
Last tech dives I was doing the other week were on doubled AL80's, and using ~40cuft for 15miniute/51m-170ft dives ... topped back up between dives as there wasn't enough gas for a worthwhile second dive (factoring in minimum gas).
Larger tanks are nicer (12L and 16L - aka HP100/HP130) as you can do either longer dives, or get a second dive out of the same set without topping up. Also, gas matching is easier as these are generally what people dive (OK, there are a lot that dive HP120's as well as others too)
_R
Last tech dives I was doing the other week were on doubled AL80's, and using ~40cuft for 15miniute/51m-170ft dives ... topped back up between dives as there wasn't enough gas for a worthwhile second dive (factoring in minimum gas).
Larger tanks are nicer (12L and 16L - aka HP100/HP130) as you can do either longer dives, or get a second dive out of the same set without topping up. Also, gas matching is easier as these are generally what people dive (OK, there are a lot that dive HP120's as well as others too)
_R
OP
I may be doing SM on the Lakes sooner than I had planned! My shop (DRIS) has a new boat on Lake Huron. I was talking with the captain today at Our World Underwater and he doesn't mind rec SM at all (and I got the unlimited season pass that covers all the DRIS boats!).
I'll be a Great Lakes divin' fool this summer. Hitting Alpena, MI/Thunder Bay - or trying to (we got blown out last summer).
I'll be a Great Lakes divin' fool this summer. Hitting Alpena, MI/Thunder Bay - or trying to (we got blown out last summer).
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OP
Pic from yesterday's pool session. Blurry, but shows nice trim.
UWZen
Registered
Those white fins are snazzy
OP
Diver-Drex
Contributor
@Marie13 - I take a third lp85 on bigger dives. During dive 1 I switch as usual until I get to 1200psi, half pressure, in one cylinder. Then I stay on the other to complete the dive. For dive two I swap in one fresh cylinder. This gives me more gas for dive 2 than if I just had a pair of 100s. And it matches up pretty well with guys diving doubled 120s.
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