Diver Dave's FGT-1D Teardown

When I got my rig, I decided to modify it so I could dive it in intermediate depths without any external bailout bottles or suit/wings inflation cylinders banging around. Plus, I wanted to add a decent harness that would accept wings. Here's how I went about it:

Here is the modified system: Essentially, I cut the tube that feeds the high pressure gauge, inserted a T fitting, and took a tap of the high-pressure gas through an isolation valve and then to a DIN block, into which I screw a normal first stage regulator to feed the drysuit, wings, and bailout regulator. The isolation valve allows the system to be de-pressurized in case of any failure of a hose or a free-flowing second stage.

Here you can see the mouth of the DIN block, ready to accept the regulator. Behind the block you can see the isolation valve peeking out from under the cylinder connection spool.

This installation is not as easy at it looks. When I first cut the tube to the original gauge, I found that the tube was not a normal type, but rather that it had an internal spiral spring to slow down a freeflow of gas in case of a ruptured gauge. Sadly, this also prevented sufficient flow to the first stage. I then needed to machine a special fitting to thread into the Draeger regulator to allow me to use standard 1/8 tube between the Dreager regulator and the Tee. That solved the problem. I kept the original flow-restricting tube between the Tee and the gauge. Yes, I have neatened up the bracket that holds the DIN block. The hose-clamp was temporary.

Here's the isolation valve, a Whitey ball-valve, located on the underside of the rig where it's protected due to the shape of the shell, yet easy to reach.

With the rig assembled, you can see the new first-stage sticking up between the starboard cylinder and the dose-regulator. All that remains to be done is to connect the hoses to the systems I desire to feed.

And here's a detail of the regulator installation.

Drysuit hose feeds from the rig at the left hip.

Long-hose bailout regulator feeds from the top of the rig.

Valve is labeled to reduce dumb-shit syndrome aboard the boat!

And lastly the VR-3 is added to the counterlung as is described on its own page.

Since I took these pictures, I've added an old Halcyon Mark-15 backplate set to the system and added a set of wings. The entire set is a self-contained SCC rebreather with backup bailout and inflation, and is ready to dive without any external complications. I'll add more photos later, this quick page was set up to share with a couple of the other FGT-1D divers. Look for more later!

	Here you can see the mouth of the DIN block, ready to accept the regulator. Behind the block you can see the isolation valve peeking out from under the cylinder connection spool. This installation is not as easy at it looks. When I first cut the tube to the original gauge, I found that the tube was not a normal type, but rather that it had an internal spiral spring to slow down a freeflow of gas in case of a ruptured gauge. Sadly, this also prevented sufficient flow to the first stage. I then needed to machine a special fitting to thread into the Draeger regulator to allow me to use standard 1/8 tube between the Dreager regulator and the Tee. That solved the problem. I kept the original flow-restricting tube between the Tee and the gauge. Yes, I have neatened up the bracket that holds the DIN block. The hose-clamp was temporary.
	Here's the isolation valve, a Whitey ball-valve, located on the underside of the rig where it's protected due to the shape of the shell, yet easy to reach.
	With the rig assembled, you can see the new first-stage sticking up between the starboard cylinder and the dose-regulator. All that remains to be done is to connect the hoses to the systems I desire to feed.
	And here's a detail of the regulator installation.
	Drysuit hose feeds from the rig at the left hip.
	Long-hose bailout regulator feeds from the top of the rig.
	Valve is labeled to reduce dumb-shit syndrome aboard the boat!
	And lastly the VR-3 is added to the counterlung as is described on its own page.