Franken-Son Diluent Addition

Franken-Son Page 2: Diluent Addition

The original IDA-71 has an excellent diaphragm actuated automatic addition valve. This valve was not originally provided with any sort of manual purge button that could be used as a manual add valve, so on the original Franken-Rig I took the low-tech road and just drilled the plastic cover so I could poke my finger in and press the diaphragm down to manually add gas. That worked great right up until I started to wear gloves. It was obvious that Franken-Son needed a manual diluent add system that could be used with drysuit gloves, so the first part of the diluent addition system was to make that happen.

Basically, I just drilled a similar hole as was found in Franken-Rig, but I then made a 2-piece purge button from white Delrin to allow use with gloved fingers.

Here's the basic idea of the button.

The first piece is the little piston that will push the diaphragm down. You can see how it will fit into the center of the original valve.

And here's where we want it in the resting position.

Adding a large head to the other side was a piece of cake with the lathe close at hand. A simple stainless-steel allen head screw holds the two pieces together.

Screw it on and we're done with the auto/manual diluent addition system. At first glance the position may seem unusual, but it's very easy to reach and is well protected.

OK, then, theres not much else to do. All we need to do is to add diluent from the cylinder to the inlet port that we fitted earlier. I decided to clean up the hose runs by using a Tee fitting to tap off the diluent to feed a second stage for bailout as well.

The tee fitting is a simple brass 3/16 barb fitting, with a stainless-steel crimp-on ring to hold it securely.

The stainless steel rings are swaged on with a special tool, and are stronger than the actual hose material. This was proven by myself by simply placing a sample of hose with a crimp fitting at the end of a LONG high-pressure hose that I connected to 3000 PSI air. When I turned on the air, the hose blew (as expected), but the crimp stayed intact. That's good enough for me.

Here's the plumbing laid into the chassis, and connected to the auto add-valve quick disconnect.

The bailout regulator feeds out of the chassis at my left shoulder. Yes, the hose is longer, I just didn't pull it all out of the chassis so I could get a good photo.

Basic BC inflator hose acts as the quick-coupling between the diluent feed line and the rig itself. This makes break-down for cleaning and servicing a breeze.

And there it all is, from cylinder to rig, with bailout. Simple, eh?

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		The original IDA-71 has an excellent diaphragm actuated automatic addition valve. This valve was not originally provided with any sort of manual purge button that could be used as a manual add valve, so on the original Franken-Rig I took the low-tech road and just drilled the plastic cover so I could poke my finger in and press the diaphragm down to manually add gas. That worked great right up until I started to wear gloves. It was obvious that Franken-Son needed a manual diluent add system that could be used with drysuit gloves, so the first part of the diluent addition system was to make that happen.
		Basically, I just drilled a similar hole as was found in Franken-Rig, but I then made a 2-piece purge button from white Delrin to allow use with gloved fingers.
		Here's the basic idea of the button.
		The first piece is the little piston that will push the diaphragm down. You can see how it will fit into the center of the original valve.
		And here's where we want it in the resting position.
		Adding a large head to the other side was a piece of cake with the lathe close at hand. A simple stainless-steel allen head screw holds the two pieces together.
		Screw it on and we're done with the auto/manual diluent addition system. At first glance the position may seem unusual, but it's very easy to reach and is well protected.
		OK, then, theres not much else to do. All we need to do is to add diluent from the cylinder to the inlet port that we fitted earlier. I decided to clean up the hose runs by using a Tee fitting to tap off the diluent to feed a second stage for bailout as well.
		The tee fitting is a simple brass 3/16 barb fitting, with a stainless-steel crimp-on ring to hold it securely.
		The stainless steel rings are swaged on with a special tool, and are stronger than the actual hose material. This was proven by myself by simply placing a sample of hose with a crimp fitting at the end of a LONG high-pressure hose that I connected to 3000 PSI air. When I turned on the air, the hose blew (as expected), but the crimp stayed intact. That's good enough for me.
		Here's the plumbing laid into the chassis, and connected to the auto add-valve quick disconnect.
		The bailout regulator feeds out of the chassis at my left shoulder. Yes, the hose is longer, I just didn't pull it all out of the chassis so I could get a good photo.
		Basic BC inflator hose acts as the quick-coupling between the diluent feed line and the rig itself. This makes break-down for cleaning and servicing a breeze.
		And there it all is, from cylinder to rig, with bailout. Simple, eh?