Scuba Tank Hooka rig

[Bushwacker]

Blue Heron expressed interest in “recipe” for subject rig, so here goes. Although you can spend big bucks and just buy an entire off-the shelf Kayak rig from Brownies (http://www.browniedive.com/kayak-diving-hose-kits) to use with an existing regulator, here’s how I did it at somewhat lower cost. Various pieces of the rig are shown in photos below. Since I already had a couple of scuba regulators, step one was to get an adapter to connect the 1st stage of regulator to the long air hose. I bought the 12” hose from the Kayak rig from Divers Direct for about $16 which attaches to the low pressure port (~150 psi) of 1st stage regulator with a male Quick Release Swivel (QRS) fittings on the other end (http://www.yachtdiver.com/brownies-parts.shtml). I also bought a couple of the $8 mating female QRS fittings and some brass fittings to connect it to a garden hose. (The dive shop guy said garden hose fittings work fine and I wanted hoses that could also be used with the “Cracker Air” gas engine powered rigs No Bones built many years ago.) I used the 2nd female fitting to connect a shop air hose to my tanks, which is real handy if you don’t have a shop air compressor or need some portable shop air! (I’ve run air tools and touch-up paint guns off that setup!) You can buy brass fittings from a dive shop to connect the hose directly to the regulator, but it’s nice to have that quick connect fitting when you’re hooking everything together on the boat because it eliminates problems with kinked hoses. I bought two 50’ 3/8” ID hoses with ½” straight thread fittings from the dive shop for about $70 ea. because I didn’t have time to order the bare hose and the crimp tools to install the end fittings. (You can order the same K3130 food grade high pressure hose for about half that price from http://www.hosexpress.com/pvc/SeriesK3130.htm, where Skip bought some longer hoses for his “Cracker Air” rig, but you’ll have to provide your own end fittings. The brass fittings are expensive! I spent about $70 at Lowes for 2 full sets of fittings, so if you can go directly from a 3/8” barbed hose fitting to the nylon garden hose fittings like Ken did you’ll save some $! It would also be cheaper to use the Brownies QRS fittings instead of the garden hose adapters, but there is no way to seal them up when the hose is disconnected, and I didn’t want moisture or critters getting in the hoses!)
My 2nd stage regulators weren’t rebuildable, so I bought a couple of used rebuilt regs from the dive shop with hoses with ½” fittings and also had them overhaul both first stages. One drawback of these type of rigs is that you don’t have a tank pressure gage as you do with a normal scuba rig, so you don’t know when you’re gonna run out of air until it gets hard to breathe! However an experienced diver knows that you can still get a couple of breaths if you just ascend a few feet, but I would want to carry a spare air bottle if using this rig deeper than about 25’! I found a good deal on some small pony tank pressure gages for $20 ea. at http://www.leisurepro.com/Prod/Categ...6/BLRPPGB.html (I see the price has gone up a bunch!), so we at least knew how much air we started with on each dive and estimate how much bottom time we’d have.
The last step was to get some garden hose female caps and make up some male PVC plugs to keep everything sealed up. The one drawback of the clear hoses is that algae can grow if they get moisture in them and they see daylight, so I keep ‘em in a bag to avoid that. Skip always flushes his out with vinegar if they’ve been stored very long, so I will probably do the same.
The innertube used is an Airhead Blast, with an ID/OD of 15”/48” and height of about 14”. The center hole is just big enough to hold 2 aluminum 80 CF tanks and it’s got plenty of flotation to hold the tanks and a dive float; the tough nylon cover provides a floor that supports the tanks and a tow strap.

Sorry for the long post but didn’t want to leave out important stuff. Obviously you need a diver certification card to get tanks filled and you should be an experienced scuba diver because this rig can kill you if you don’t know what you’re doing! We made an exception for Sandy because he promised to take a certification course, and besides, he knows just enough to be dangerous anyway! Fire away if any questions! Denny