Starting down the DH rabbit hole

[Nemrod]

You may know this but it never hurts to remind everyone. NEVER inhale directly from the can horn. The venturi can be very aggressive and serious lung damage can occur if you inhale from the horn and the venturi kicks in hard. Always use a hose loop when testing a DH cracking pressure or Venturi.

I have had people laugh at me about this. This is real. And I suggest not to do this especially with a single stage like Mistral because that Venturi is shooting full tank pressure right down the throat. Might get away with it 10 times, maybe a hundred times, maybe not even one time! Just saying. Put a hose loop on.

James

 

[James79]

So, Saturday I got a little under an hour on it at Vortex Springs (going while the going is good still). Setup was same as above, but with a tank that has the HP port on the valve, so I could monitor pressure. 3mm full suit, and 1.5 lb on the cam band.... and I probably could have done with out the lead.
Most importantly, I enjoyed the hell out of it.... I see more DH time in my future. Reg behaved same as above, so I will have to crack it open, add a washer, and re-tune. Death Wish Engineering wing MK3 is minimal as all hell.... I'm guessing 15-18 lb lift. I'll have to check it thoroughly in the pool.
Next on my list is to finish a 3d printed mouthpiece modeled on the Hope Page design concept. I'm adapting it for 1 inch hoses (gas mask hoses), but the design will be adaptable for any hose, with just the end pieces being unique to the hose size.
I dig the doublehose, both as a history lesson, and as a wonderful way to dive. My SAC was up, but I attribute that to a combination of getting comfortable with DH regs still, and that periodic free flow. I'll see what practice brings.
Respectfully,
James

 

[James79]

Started a thread in the diy 3d printing forum for the mouthpiece project;
Hope Page inspired double hose mouthpiece
Any input, critique, and ideas appreciated
Respectfully
James

 

[James79]

Well, I bought a RAM a little while ago from someone on VDH forum, and am just now getting to it. I ran into a problem of the exhaust horn being so close to the can lip that a band clamp (even recessed for the horn) wouldn't fit. I thought about trimming the band clamp even further, but I have an Ebay rescue DAAM that I can use that on unmolested. So, I went a different direction... What's old is new again. Somewhere in the VDH archives I had seen an advertisement for screw clamps to replace the c-clips..... So, I reproduced the idea in plastic with M3 nuts/screws.

DH_Can_Screw_Clamp_Installed.jpg (65.18 KiB) Not viewed yet

DH_Can_Screw_Clamps.jpg (49.64 KiB) Not viewed yet
Not as easy to install/remove as the band clamp.... but made with what was on hand (can't beat the price!).
Respectfully,
James

 

[Luis H]

I like the band clamp as the best closing device for the vintage cans, but this screw clamps seem like a reasonable alternative to the early bent clips. And yes, the band clamps are very vintage. They have been around since the 50's (in case someone questions it).

I have seen pictures of screwed on replacement clamps similar to those. The ones I have seen were after market replacements and I believe they were made out of brass.

You may not be able to get as much clamping force with the plastic ones, but you can make up the clamping force by adding more clamps. There is no rule that tells you that you should only use 7 clamps. Obviously adding more is more hassle when closing or opening the can, but you do need enough clamping force so that the cans do not slip if you try to rotate the horns and so that it doesn't leak past the diaphragm.

Even having extra clamps, it would still be less hassle to open the regulator with this screw clamps than with the original clips. I never liked those clips.

And you do want to get in the habit of regularly opening the cans and rinsing the regulator with fresh water and letting it dry.