- Messages
- 13,633
- Reaction score
- 10,370
- Location
- Port Orchard, Washington State
- # of dives
- 1000 - 2499
OMS single dive setup. What parts to get???
- Thread starter Speardoggin
- Start date
Please register or login
ucfdiver
Contributor
- Messages
- 13,633
- Reaction score
- 10,370
- Location
- Port Orchard, Washington State
- # of dives
- 1000 - 2499
PfcAJ
Contributor
D00d, you just swim down, swim around, and swim back up. Its nbd.
Slamfire
Contributor
IMHO, backplates are better suited for doubles. You can use them with singles, but they will be less stable. You can use a single tank adapter (STA) for improving stability, but, like the name implies, it's an adaptation of the original intent. But more importantly than backplates, the added redundancy in your gas supply is a more compelling reason to use doubles.
With doubles and your Al 40 you would have three different gas sources that could be independently isolated with the right manifold if required. Three is better than 2. You are not using a drysuit or redundant buoyancy. If your wing fails, swimming up with a steel 130 is going to be much harder than swimming up with double Al 80's. Even if you drop your 4 lbs of weight, it's still going to be difficult. A full steel 130 is 11.7 lbs negatively buoyant and 2 lbs negative when empty. Twin Al 80's will be 2.8 lbs negative when full and 8.8 lbs positive when empty. They are 3 lbs positive when they are halfway.
Twin Al 80's will hold 23.4 ft3 more than a steel 130. More gas is good. Above the surface, twin Al 80's will weigh only 19.8 lbs more than a steel 130. Al 80's are so common that it is not hard to find used cylinders for very good prices. You could probably sell your steel 130 and buy two Al 80's with the money from the sale. Just be careful to stay away from the 6351 alloy.
I realize that a 200' spearfishing dive is not the same as a 200' wreck penetration dive or a 200' cave dive. Back in the days when I did spearfishing, I would always do it without tanks. I would spot a fish from above while breathing then drop down to 45'-60' to do the stalking and harvesting of the fish. Needless to say, my bottom time was limited; I am no Enzo Maiorca. I imagine that your deep dives are somewhat similar. You'll spot the prey from above and then drop down to harvest it, spending as little time as possible at the bottom. This would keep your deco obligations at low levels. I'm not going to turn this thread into another deep air debate, but I'll just say that narcosis is real. It will affect different people in different ways and in different intensities. You have to be very aware of this.
I'll close with this pic of my grandfather c. 1964. He got this fish while diving with my father, who was 14 years old at that time. Spearfishing can be very fun.
With doubles and your Al 40 you would have three different gas sources that could be independently isolated with the right manifold if required. Three is better than 2. You are not using a drysuit or redundant buoyancy. If your wing fails, swimming up with a steel 130 is going to be much harder than swimming up with double Al 80's. Even if you drop your 4 lbs of weight, it's still going to be difficult. A full steel 130 is 11.7 lbs negatively buoyant and 2 lbs negative when empty. Twin Al 80's will be 2.8 lbs negative when full and 8.8 lbs positive when empty. They are 3 lbs positive when they are halfway.
Twin Al 80's will hold 23.4 ft3 more than a steel 130. More gas is good. Above the surface, twin Al 80's will weigh only 19.8 lbs more than a steel 130. Al 80's are so common that it is not hard to find used cylinders for very good prices. You could probably sell your steel 130 and buy two Al 80's with the money from the sale. Just be careful to stay away from the 6351 alloy.
I realize that a 200' spearfishing dive is not the same as a 200' wreck penetration dive or a 200' cave dive. Back in the days when I did spearfishing, I would always do it without tanks. I would spot a fish from above while breathing then drop down to 45'-60' to do the stalking and harvesting of the fish. Needless to say, my bottom time was limited; I am no Enzo Maiorca. I imagine that your deep dives are somewhat similar. You'll spot the prey from above and then drop down to harvest it, spending as little time as possible at the bottom. This would keep your deco obligations at low levels. I'm not going to turn this thread into another deep air debate, but I'll just say that narcosis is real. It will affect different people in different ways and in different intensities. You have to be very aware of this.
I'll close with this pic of my grandfather c. 1964. He got this fish while diving with my father, who was 14 years old at that time. Spearfishing can be very fun.
OP
Speardoggin
Contributor
Nice pic. That's a good one for the wall. I prefer to freedive while spearing, but some of the deep wrecks are obviously too deep. I plan on taking the GUE level 1 course within the next year if possible and go to doubles then. Everytime I add up the money required for everything, it ends up being more than I can chew right now. That is a good point about twin 80's with a wing failure. I believe my Faber HP 133, according to their site, is 9.1 negative full and about 2 positive empty believe it or not. BTW, where was the fish caught?
Slamfire
Contributor
Good clarification on the Faber steel cylinder. I was referring to Worthington's (XS Scuba) steel 130. GUE, interesting... 
Honestly, they have an excellent program. Some of the contributors to this thread are GUE alumni.
I believe the fish was taken around Omoa, in the mainland Honduran Caribbean coast. My grandfather used to have a house about 1 km away from the San Fernando Fortress, which was constructed from 1756-1775.
Honestly, they have an excellent program. Some of the contributors to this thread are GUE alumni. I believe the fish was taken around Omoa, in the mainland Honduran Caribbean coast. My grandfather used to have a house about 1 km away from the San Fernando Fortress, which was constructed from 1756-1775.
OP
Speardoggin
Contributor
Sweet!
- Messages
- 541
- Reaction score
- 34
- # of dives
- 5000 - ∞
This thread is a Trainwreck!! Scubaboard FTW!!!
ucfdiver
Contributor
Similar threads
