DY Jet Scare Experiment

[Bryan]

Remember the heavily modified Spiro nozzle I had so much trouble with??? Here is the link to the story if you don’t....SPIRO STORY CLICK HERE

Anyway I decided to experiment with it again since almost popping a lung twice before while using it was not enough…..Scenario is a little different though. The DY Jet Scare does not have a venturi assist nozzle. Never did as far as I know. And they also differ in the fact that the nozzle it does have does not point right straight down the can like on a Spiro and a few other regulators. So be that as it may I have installed the whacked out Spiro nozzle on my Jet Scare and as far as bench tests go it breathes a ton better than with the non venturi standard DY nozzle…..Now the big question is??? Will it go haywire and make me embolize or blow a hose off a 200’? Only open water testing will tell. That comes next week in Florida.

[1stab]

I hate YOU!

I think that setup is going to work very well depending on lever adjustment.

Dive it in good health!

[Nemrod]

It should not kill you as long as:

1) The hoses are installed--correctly
2) a functioning cage valve is installed in the mouthpiece--with
3) the mouthpiece installed correctly--and
4) the exhaust hose is open either to the atmosphere or if in the water it is properly installed in the can with a functioning duckbill

This should reduce the shock effect of a wide open nozzle/venturi to a level that will not blow your lung wall out--at least before you can spit it out.

Please be careful with compressed air--a fellow at work got a subcutaneous injection of air playing with the air nozzle at only 90 psi--it found a tiny cut . It was a mess and he is on antibiotics etc to prevent infection of the arm. Can you imagine super staff getting in there .

Nemrod

[Robohips77]

Do you think they never installed a venturi assist because 1. They had not invented or tested it (which I think you already answered since it was in other regs alread)? 2. Not Cost effective? 3. Was not deemed appropriate for this reg for potential stress reasons 4. Maybe they attempted and it simply did not meet the standards they were looking for? 5. any patent infringement? Just curious as is obvious from my questions I am not an engineer or historian on this reg but I find it interesting this was not done for this unit! Will be waiting for the results. Enjoy your trip.

[Bryan]

This is my theory and opinion on why……Please don’t take it as fact.

1. The case design of the DY did not lend itself to the longer venturi nozzle. The photos should make it more clear when you compare the DY with the Mistral/Stream Air can.
2. USD never threw anything away during the early days as we have heard from several sources. So therefore the nozzles had to be used!
3. It was the most inexpensive regulator of the bunch and they didn’t want it to perform on par with it’s more expensive counterparts.

[Bryan]

It should not kill you as long as:

1) The hoses are installed--correctly
2) a functioning cage valve is installed in the mouthpiece--with
3) the mouthpiece installed correctly--and
4) the exhaust hose is open either to the atmosphere or if in the water it is properly installed in the can with a functioning duckbill

This should reduce the shock effect of a wide open nozzle/venturi to a level that will not blow your lung wall out--at least before you can spit it out.

Please be careful with compressed air--a fellow at work got a subcutaneous injection of air playing with the air nozzle at only 90 psi--it found a tiny cut . It was a mess and he is on antibiotics etc to prevent infection of the arm. Can you imagine super staff getting in there .

Nemrod

Very good advice James!! Thank you! The reason I think it works in this regulator is because the nozzle is not aimed directly down the can. And by having the airflow impeded by part of the can wall it is preventing the out of control free flow that I had in the Spiro. At the same time the venturi effect improves the breathing drastically over the original nozzle.

[JES]

Could this be the start of a Jet-Scare breathing improvement upgrade kit?

[Bryan]

Could this be the start of a Jet-Scare breathing improvement upgrade kit?

More likely to be the start of a Crazy Lawsuit Game! I think I'll leave the nozzle modifications to the individual.....

[JES]

More likely to be the start of a Crazy Lawsuit Game! I think I'll leave the nozzle modifications to the individual.....

In today's litigious world, that's probably a wise decision....

[1stab]

Any long nozzles lyin' around that may be lookin' for a home?

[YankDownUnder]

Bryan,

I don't think you will have any problems at all. The Heinke venturi points directly down the hose horn and mine breathes perfectly. It is a two stage regulator, so that could be a difference. The Heinke venturi directs a lower pressure.

As safety is the most important thing, take a bail-out tank with you in open water. Every 'Jet' pilot has a parachute.

[Bryan]

Bryan,

I don't think you will have any problems at all. The Heinke venturi points directly down the hose horn and mine breathes perfectly. It is a two stage regulator, so that could be a difference. The Heinke venturi directs a lower pressure.

As safety is the most important thing, take a bail-out tank with you in open water. Every 'Jet' pilot has a parachute.

The fact that it was pointing directly down the horn is EXACTLY the reason it would not work in the Spiro but may indeed be the reason it WILL work in the Jet Air. Here is the whole story. It's also linked on my very 1st post at the top of this thread if the link does not work

SPIRO NOZZLE STORY LINK