help with doubles
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SparticleBrane
Contributor
You really shouldn't be thinking about doubles with <25 dives...
Well, you need a manifold, a set of bands, and two tanks.
The devil is in the details.
I use Thermo manifolds. There are a half-dozen other manufacturers. They vary based on criteria like "how many O-rings there are to seal locations where one part of the manifold connects to another" or "how many turns does it require to open or close the valve".
I use Highland bands. There are likely a half-dozen other manufacturers. They vary based on material used, welds, the width of the bands themselves, and the rigidity/thickness of the material used.
I currently own two sets of PST E8-130s, and one set of Luxfer 3300 psi neutral 80s.
A set of PST E8-130s, all components new, would run pretty close to $1000 with tax.
Its tough to find PST E8-130s these days. Other guys can tell you what their sets of steels cost to set up.
Aluminum 80s used to be somewhat cheaper, but the neutral Luxfers will run you around $225-230 apiece these days, add bands and manifold and I'd be surprised if you didn't wind up spending between $700 and $800 or so to go from no doubles to a set of new Luxfer neutrals VIPed and filled.
Be advised that costs for a set of doubles are going to vary tremendously based on which tanks you use. Steel tanks vary in both length as well as width - you're looking for a set of tanks (identical) that fit your particular body type and build, as well as a set you can lift and carry around (full), as well as a set that meets your needs in terms of logistics for the dives you're doing. Steel tanks are often preferable, (but not always,) because you tend to avoid swings from negative to positive bouyancy with them and they remove the requirement for some of the lead weight you must otherwise wear. But they are generally considerably more expensive than aluminum tanks. If you are diving in a wetsuit, aluminum doubles are generally safer than a very large set of steel tanks.
It's often useful to find a mentor and work with that person when you get to the point of moving into doubles. But based on information you've provided I'm not sure you're there yet.
One key feature of doubles is that they provide you with sufficient gas that you can really get yourself into serious trouble - staying too deep for too long, and going into deco when you're neither trained nor experienced in planning and conducting decompression dives.
Things like decompression, done wrong, can land you in a wheelchair for the rest of your life. It isn't anything to underestimate.
So be careful with your doubles, should you choose to move in this direction, work with a mentor and take courses in extended range, advanced nitrox, and beginning deco diving to ensure that you will use the equipment safely.
FWIW. YMMV.
Doc
The devil is in the details.
I use Thermo manifolds. There are a half-dozen other manufacturers. They vary based on criteria like "how many O-rings there are to seal locations where one part of the manifold connects to another" or "how many turns does it require to open or close the valve".
I use Highland bands. There are likely a half-dozen other manufacturers. They vary based on material used, welds, the width of the bands themselves, and the rigidity/thickness of the material used.
I currently own two sets of PST E8-130s, and one set of Luxfer 3300 psi neutral 80s.
A set of PST E8-130s, all components new, would run pretty close to $1000 with tax.
Its tough to find PST E8-130s these days. Other guys can tell you what their sets of steels cost to set up.
Aluminum 80s used to be somewhat cheaper, but the neutral Luxfers will run you around $225-230 apiece these days, add bands and manifold and I'd be surprised if you didn't wind up spending between $700 and $800 or so to go from no doubles to a set of new Luxfer neutrals VIPed and filled.
Be advised that costs for a set of doubles are going to vary tremendously based on which tanks you use. Steel tanks vary in both length as well as width - you're looking for a set of tanks (identical) that fit your particular body type and build, as well as a set you can lift and carry around (full), as well as a set that meets your needs in terms of logistics for the dives you're doing. Steel tanks are often preferable, (but not always,) because you tend to avoid swings from negative to positive bouyancy with them and they remove the requirement for some of the lead weight you must otherwise wear. But they are generally considerably more expensive than aluminum tanks. If you are diving in a wetsuit, aluminum doubles are generally safer than a very large set of steel tanks.
It's often useful to find a mentor and work with that person when you get to the point of moving into doubles. But based on information you've provided I'm not sure you're there yet.
One key feature of doubles is that they provide you with sufficient gas that you can really get yourself into serious trouble - staying too deep for too long, and going into deco when you're neither trained nor experienced in planning and conducting decompression dives.
Things like decompression, done wrong, can land you in a wheelchair for the rest of your life. It isn't anything to underestimate.
So be careful with your doubles, should you choose to move in this direction, work with a mentor and take courses in extended range, advanced nitrox, and beginning deco diving to ensure that you will use the equipment safely.
FWIW. YMMV.
Doc
I know it's not the # of dives that count, but what's the general consensus on experience level recommended before one gets into doubles? Good with buoyancy at all depths, trim, proper weighting? Never until you're in a class?
cinder4320
Contributor
I dove doubles before class so I didn't end up in a cave class, trying to learn for the overhead environment with totally new gear. My husband and I dove our pool before heading out anywhere in doubles.
When we were ready we went to a pretty safe site (a nearby spring) and he dove with his doubles first. I stayed on a single tank until he felt comfortable then I dove my doubles. We didn't want to both be in new gear at the same time.
Truthfully it was not a big change except for the walk to and from the site!!
Miranda
Different divers will have different perspectives.
Here is my opinion:
When you plan a complex dive, you need to set aside an amount of gas sufficient to bring both yourself and your buddy to the surface from the deepest point of the dive/farthest penetration.
With that portion of the gas in your tank set aside, you plan to use the remaining gas in the tank according to other environmental parameters, such as whether you're in an overhead environment, or whether its critical that you swim back to an upline/anchorline before beginning your ascent. In the case of the former you may divide the remainder of your gas into thirds, and plan one third in, one third out, and the remaining third for 'issues' if these occur. In the case of the latter, you may divide your remaining gas into halves, or 'halves + X psi" ...going outbound on one half and returning on the other with some excess allowed.
The point is that when you begin to reach a situation where you can no longer execute the dives you want to do safely, because you cannot set aside the amount of gas necessary to bring you and your partner to the surface safely from the deepest/farthest point of your dives and still have enough left in your tank to conduct the dive, then you can begin thinking about doubles.
Typically, however, before a diver has hit this point they have learned a great deal about calculating gas consumption, the impact of deeper depths on consumption calculations, gas planning for emergency response situations, and other mixed gas requirements for advanced nitrox and extended range diving.
When you can no longer do the dives you want to do on a single tank (even a large one), then its time to move to doubles. But those are pretty complex dives relative to most recreational diving, and by the time a diver reaches that point in the progression it is less likely that they'll do a recreational dive in doubles and stay too long too deep...
IMHO...YMMV.
Here is my opinion:
When you plan a complex dive, you need to set aside an amount of gas sufficient to bring both yourself and your buddy to the surface from the deepest point of the dive/farthest penetration.
With that portion of the gas in your tank set aside, you plan to use the remaining gas in the tank according to other environmental parameters, such as whether you're in an overhead environment, or whether its critical that you swim back to an upline/anchorline before beginning your ascent. In the case of the former you may divide the remainder of your gas into thirds, and plan one third in, one third out, and the remaining third for 'issues' if these occur. In the case of the latter, you may divide your remaining gas into halves, or 'halves + X psi" ...going outbound on one half and returning on the other with some excess allowed.
The point is that when you begin to reach a situation where you can no longer execute the dives you want to do safely, because you cannot set aside the amount of gas necessary to bring you and your partner to the surface safely from the deepest/farthest point of your dives and still have enough left in your tank to conduct the dive, then you can begin thinking about doubles.
Typically, however, before a diver has hit this point they have learned a great deal about calculating gas consumption, the impact of deeper depths on consumption calculations, gas planning for emergency response situations, and other mixed gas requirements for advanced nitrox and extended range diving.
When you can no longer do the dives you want to do on a single tank (even a large one), then its time to move to doubles. But those are pretty complex dives relative to most recreational diving, and by the time a diver reaches that point in the progression it is less likely that they'll do a recreational dive in doubles and stay too long too deep...
IMHO...YMMV.
Dirkadiver
Contributor
I don't like making assumptions about skill level based on # of dives, but rather how you plan to approach the next step; in this case going to doubles. If you're going to rely on the internet to teach you, you shouldn't be doing it. If you're just checking costs, necessities, etc., with the intention on taking appropriate training then press on.
As to your question, save up. Actual cost obviously is going to vary depending on brands, new, used, ebay, retail, etc, etc. I'd be prepared to spend about 5 grand, which should cover your tanks, drysuit, regs, bands, bp, wing, harness, lift bags, reels, manifold, lights, hoses, hood, gloves & maybe a candy bar.
It's not cheap and as soon as you think you've got everything, you'll need 2 more regs & stage bottles & another set of doubles, then a couple more regs, then maybe a couple more regs:11:.
As to your question, save up. Actual cost obviously is going to vary depending on brands, new, used, ebay, retail, etc, etc. I'd be prepared to spend about 5 grand, which should cover your tanks, drysuit, regs, bands, bp, wing, harness, lift bags, reels, manifold, lights, hoses, hood, gloves & maybe a candy bar
.It's not cheap and as soon as you think you've got everything, you'll need 2 more regs & stage bottles & another set of doubles, then a couple more regs, then maybe a couple more regs:11:.
I just finished building a set of 119's. The damage breaks down like this;
2 Worthington X-8 119's $650.00
Highland bands $120.00
Sea Elite manifold $200.00
2 Scubapro MK25's $700.00
S600 $350.00
RG2010 $200.00
Hoses $90.00
SPG $65.00
Backplate $65.00
Webbing, tri-glides, d-rings, bolt snaps, and buckle $45.00
Bungee, cave line, and inner-tube $5.00
Wing $350.00
Total price, give or take a few bucks = $2840.00
2 Worthington X-8 119's $650.00
Highland bands $120.00
Sea Elite manifold $200.00
2 Scubapro MK25's $700.00
S600 $350.00
RG2010 $200.00
Hoses $90.00
SPG $65.00
Backplate $65.00
Webbing, tri-glides, d-rings, bolt snaps, and buckle $45.00
Bungee, cave line, and inner-tube $5.00
Wing $350.00
Total price, give or take a few bucks = $2840.00
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