Handing "Doubles"

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Doubles (two scuba cylinders connected with a common manifold) are heavy and awkward. They typically weigh between 70 and 100 pounds (30-45 kg). Below are a couple of non-diving utensils that I have added to my equipment locker to assist me in handling the cylinders.

I found this "Bench Top Pro." cart below at a K-mart. This metal (all but wheels) cart folds for easy storage (20" x 28" x 3"; 51 cm x 71 cm x 8 cm) and transport. It quickly opens to a small cart ideal for a set of doubles. The cart is used primarily for moving the cylinders over flat surfaces, especially between my SUV and the dive shop for gas refills. I added a small bungee cord as a safety margin for securing the cylinders. The cart and the bungee cord together had a cost of about $40.00.

Although I like the small folded size of this particular cart, any cart that is easily transported will make the transfer of heavy multiple cylinders from a vehicle to fill-station or charter boat a much easier task.


Folded Cart	Cart With Twin "80's"

The twin 80's were my first set of doubles and the manifold between the cylinders is a Benjamin Cross-over. It shows, as one dive vendor commented, that I "am steeped in tradition" (probably the politically correct way of saying "old diver.")

The cart is useful only in relatively flat areas and is almost totally useless for severely inclined or stair step areas. For these regions, I use a shoulder strap (thanks to Tyler Schultz of Michigan Adventure Diving for the shoulder strap idea.). I use a cam-shackle on a 6 foot strap. The cam shackle has the advantage that the buckle will not slip under tension. This particular model is rated at holding 2500 pounds of thrust with a dead load of about 800 pounds. (I prefer a rating far in excess of anticipated load). Because the hooks are open, I added a couple of Velcro wrist watch straps to wrap around the manifold to keep the hooks in place. These straps are simply placement holders; the load is born by the hooks. Finally, I added a couple of automobile seat-belt pads (one to hold the excess strap and the other as a shoulder pad). The total cost for two strap assemblies (the cam-shackle I chose came only as a set of two.) was less than $40.00. As a bonus, my Jeep Cherokee has a set of rings in the rear floor board, so I use the second cam-shackle strap to secure the scuba cylinders resting in the storage transport rack (see Scuba Storage Rack. ) when carrying cylinders in my vehicle.

When using the strap, it is important that the exposed end of the bolts securing the cylinder bands be oriented away from the diver. Otherwise, it is possible that the extended bolts can scrape against or cut into the leg when the set of doubles is lifted from the ground.. This is especially critical when wearing shorts.


The "Strap"	Using the Strap (with Twin 95's)

While it is certainly not necessary to have "accessories" for handling multiple cylinder configurations out-of-water, they do make the transport of these heavy packages a bit more convenient. As the "Easy Diver" always says, "Dive with your brains, not your back!"

Larry "Harris" Taylor, Ph.D. is a biochemist and Diving Safety Coordinator at the University of Michigan. He has authored more than 100 scuba related articles. His personal dive library (See Alert Diver, Mar/Apr. 1997, p. 54) is considered by one of the best sources of information in North America.

Use of these articles for personal or organizational profit is specifically denied.