Trip Report: First dive with my "new" PRAM.

[rx7diver]

I didn't know whether to place this in the Solo Diver forum or here in the Vintage Diver forum. So, being a statistician, I flipped a coin!

Just back from the neighborhood quarry. Swim trunks, tee shirt, mask, Jet Fins (no booties), snorkel, no weightbelt, plastic backpack (no BC) with single-piece nylon harness, Luxfer Al 63, and my new, pre-owned US Divers DA Aqua Master double hose regulator modified with a 1st-gen Phoenix first stage, diaphragm, duckbill, hoses, and wagon wheels. Spent about an hour underwater altogether, shallow, skirting the edge of the quarry, back and forth, while my twins played above on the surface. First time doing a dive in only this most basic gear. First time using a double hose reg in open water. So liberating! Such a delight! The myriad fish, some very large, some mere minnows, swam with me, almost touching my faceplate, no exhaust bubbles to frighten them off. Everyone should dive so at least once!

Safe Diving,

rx7diver

 

[herman]

Welcome to the world of vintage DH diving. It is a liberating experience. I think the thing that most amazed me is the amount of drag that was reduced by removing all the unnecessary junk. Now you know the experience JC described as being a man-fish.

 

[TN Traveler]

I am glad to see that my "old" PRAM is going to be used and enjoyed. Welcome to the "Dark Side".

 

[rx7diver]

Thanks, Herman and TN Traveler. Next steps are to try (again!) a crotch strap, and replace my harness webbing with something softer (and with a quick-release!) so that I can lose the tee shirt.

I dove only with my self-winding diver wristwatch, an old US Divers SPG (supplied with the PRAM by the previous owner), and a small Gerber knife on my waist strap. So, next dive I'll add my wrist-mount analog depth gauge, a wrist-mount analog compass, and an old small waist-mount pocket containing EMT shears (our major concern here in the US Midwest is fishing line, especially fishing line having wire leaders attached), submersible dive table, Storm whistle, and diver's emergency mirror.

And I'm almost certain that I will need to add a weight belt holding ~1-2 lbs (to accommodate a near-empty Al 63; my inaugural PRAM dive left ~2,200 psig remaining in my Al 63).

Hopefully I'll soon be able to try this "most basic gear configuration" in Table Rock Lake or Bull Shoals Lake, large clear Army Corps of Engineers lakes located in southwest MO/northwest AR, about 3-5 hours from my house. This gear configuration should work beautifully diving there from late July through late September, down to ~20-25 ffw (i.e., above the first thermocline).

I doubt, though, that I will continue to dive this "most basic gear configuration" after these initial experiments are concluded. I've long believed that a rec diver "must" be able to float on the surface (on his/her back, mouth and nose well out of the water), in his/her full scuba kit, wearing a completely full scuba cylinder and completely empty BC (if he/she is wearing a BC), perhaps after dropping *only* his weight belt. So, for me personally, this means I "must" wear a wet suit in fresh water. I think my 3/2 O'Neill jumpsuit will work fine here for this BC-less diving.

Safe Diving,

rx7diver

 

[simonbeans]

Try a steel 72 with a harness and you can forget the Al buoyancy swing.

 

[rx7diver]

Try a steel 72 with a harness and you can forget the Al buoyancy swing.

Simonbeans,

My steel 72 won't work for me and the particular blow-molded backpack I own, I don't think. The Phoenix nozzle makes the PRAM a bit thicker, which prevents the narrow (6.9" diameter) 72 from being dropped down far enough in my backpack. The wider Al 63 (7.25" diameter) doesn't present this particular problem.

I actually attempted to fit my PRAM first to my OMS 46 (Faber LP 46) with my backpack, then my 72 with my backpack, and then, finally, a rented Al 63 with my backpack. Third time's the charm!

Maybe if I wore a crotch strap, I could loosen my shoulder straps a bit more and drop my backpack lower down my back, and the 72 would work. But I don't at this time (never have liked them), though I intend to try a crotch strap again soon if possible.

Safe Diving,

rx7diver

 

[Luis H]

This back plate was specifically designed to fit any double hose regulator (modern or vintage). It will place and hold the regulator in the correct position and will help prevent the cylinder from rolling or rotating.
You can use with or without a wing.


Store - Vintage Double Hose


Crossing the straps as shown below controls the regulator right between your shoulder blades. The picture show a Phoenix regulator with a steel 72.
As you can see the regulator will be almost touching your back. That provides the best breathing performance.

 

[Luis H]

Maybe if I wore a crotch strap, I could loosen my shoulder straps a bit more and drop my backpack lower down my back, and the 72 would work.

rx7diver

The problem with the harness straps attached lower on the tank is that it allows the tank and regulator to move side to side. It allows the regulator to move too much.

That is the reason the DH backplate has a cutout specifically for the regulator and the shoulder straps attach right below the regulator and they cross right on front of the regulator (and between your shoulder blades).

Also notice that the plate has slots for two tank bands that will control the cylinder and will match the two standard wing slots pattern available today.

 

[Nemrod]

Not only is the Luis designed VDH plate the best plate for DH regulators, with or without a wing, but it is just completely dandy with single hose regulators. I use it with both and it is perfect for all regulators. I did tweak mine to better suit me but that was all minor.

N

 

[george_austin]

Second the great reviews of the VDH plate for DH use. There is no noticeable roll with my steel 72 using hi/low tank straps and that can is right where it's supposed to be.

As far as setting up your blow molded pack ( I use one for diving my SP Mk 5 and some diffeent tanks) - I like using 2" rubber for the harness which I get in rolls from Trident - you'll need the wire buckles as well but damn, that set up is comfy!

enjoy the PRAM - I love using mine as its a completely dependable piece of equipment and a real showstopper on the boats. People see us diving them with no wings and kind of freak out