IDA-71 – It Works but …

Mossyback · 18th February 2008, 15:28

Although I’ve dived my “71” several times on O2, I just spent 1 + hours on the bottom of the pool using it as a mixed gas unit. It functioned just fine! The manual add with the 0.5L snubber work just fine. I used Dave Sutton’s design. The ppO2 set-up - again Dave and Mark Munro’s design worked perfectly. I did several switches from the loop to a bailout bottle and back again. No problems. When I got home I tore the rig down expecting to find some water inside. Not a drop! I zipped open the counterlung and it was dry. I removed both scrubbers and they also were dry. With only 20 days to go before our Bahamas trip, things are looking good but …….

I’ve got one problem to solve and I need input. I find the ADV very hard to reach to do a diluent flush. I’d like to add to the diluent side a similar set-up as I use to add O2.

The LP feed off the diluent regulator goes into the CL and directly to the ADV, therefore I can’t inject directly into the bag from this line. The only other entry point directly into the CL is through the O2 feed. Will the following solution work? I can run a hose from a LP port on the Diluent reg., through a Clippard valve to a “T” fitting on the O2 line before it enters the CL. This would allow for a manual flush into the bag.

Comments?

Hank

Skipbreather · 18th February 2008, 16:44

Hi Hank-

There is another option for where to add the dil that- since you have a bag zipper- is a one evening mod if you have access to a lathe. It has the added benefit of cleaning up the inside of the bag considerably by eliminating the hose connecting the OP valve to the OP vent at the top of the bag/ case.

1. Zip open bag.

2. Remove OP vent hose.

3. Block OP valve outlet.

4. Drill a few holes in plastic OP valve cover.

5. Remove metal OP vent fixture from top of case & bag (save the nut).

6. Make the small brass plug pictured (more below).

7. Mount brass plug to bag & case (reuse the nut).

8. Zip bag closed.

9. Connect dil line- controlled by valve of your choice- to brass plug.

The brass plug is sized to replace the original metal vent fixture exactly, down to cutting the same threads. In the center of the plug simply cut threads (1/8 pipe or 3/8-24) to fit the hose or quick disconnect fitting of your choice. In the picture, I've just put a standard 3/8-24 port plug in the brass plug- I had not yet connected it to a hose.

Hope this helps,

Ken

jmhardingjr · 18th February 2008, 16:45

I've never dived an IDA-71 but Dave Sutton claimed that with the ADV modification he made (the plastic disc and plunger, Franken-Son Diluent Addition) allowed him to do a dil flush by rolling his head back to activate the ADV. Apparently, if the rig is sitting high enough on your back you can just look up lean you head back to push on the little external button he put on his rig.

Just a thought.

Jay

Corallaro · 18th February 2008, 16:46

Hi

See my solution:

http://www.rebreatherworld.com/home-...tml#post121281

manual oxigen and manual diluent buttons over shoulders with modded clippard valves

manual diluent input directly over sensors and so into counterlung
(big white hose for display, little white hose for diluent gas)

the system works perfectly, for me

Giovanni

Mossyback · 18th February 2008, 18:33

Hi Guys,

Thanks for the quick feedback.

1. Jay, I can't do Dave's "button" solution because the Oxycheq wings that I'm using come up above the "71" at the top. I can reach the ADV but it's a real struggle. I guess I could replace the wings with some of a different design.

2. Ken, I just had a look inside the CL and I think I understand what you're sugggesting. The OP valve has the hose that re-routes the gas over your shoulder. By removing the hose, plugging the OP outlet and drilling holes in the small plastic "O" ringed cap, the exhausted gas is forced out through the OP plastic cap. I then machine the brass fitting and route my diluent gas flush through that opening and into the CL. Am I correct? BTW, it looks like you just taped a plug in the OP hole. I guess there's not much pressure differential involved is there?

3. Giovanni, It appears that you've managed to obtain very small diameter hoses for your gas supplies. Can you give me the diameter of them and the operating pressure? Can you get sufficient volume through them? Things are pretty crowded inside my case and It would help if I could reduce the hose size.

Hank

Corallaro · 18th February 2008, 18:44

Hi Mossy...i send a my old post..............

i use rilsan 4x2 millimeters and only for internal hidraulics

----------------------------------------
Hi

this is the configuration of my modded IDA-71

note: the 71 have only one counterlung, the inhale couterlung

oxigen line:

a) as a first stage i use the classic APEKS DS4 with cap to fix IP
b) as filter i use a McMastercarr Filter 10 micron
c) as orifice i use the .003 orifice from the same company that makes them for jetsam.
d) as "OR VALVE" (to protect orifice) i use a Clippard MJSV-1
e) as MAV i use a Clippard MJV-2 push valve + security spring
f) for internal hydraulics i use Rilsan PA 11 4x2 hoses (44 bar) with AIGNEP push in fittings (only 15 bar)

diluent line:

a) as a first stage i use any first stage (original IDA for internal diluent)
b) as MAV i use a Clippard MJV-2 push valve + security spring
c) for internal hydraulics i use Rilsan PA 11 4x2 hoses (44 bar) with AIGNEP push in fittings (only 15 bar)

it is not possible to use with quick disconnect underwater with orifice, it will be clogged
the oxigen in, is first the scrubbers
the diluent in after MAV, is in the same P-Port that i use as for sensors

the MAV (Clippard MJV-2) havent any flow reductor, probably the use of little Rilsan PA 11 4x2 hoses give the right flow.

with this configuration is all ok without spikes and with right (for me) flows for the MAVs (oxigen and diluent)

Giovanni

jaap · 18th February 2008, 18:52

If you need ideas for other simple points to feed gas into the rig, how about adding a feed on you pO2-probe? Or via the filling caps to the scrubbers (a bit far from the cells if you want to do a dil/sensor drill).

But do you really need a manual way of manually adding dil at this stage? How about dil flushing by activating the ADV blowing some gas out the nose or sticking the tounge in the mouthpice and exhaling around it out into the water?

Skipbreather · 18th February 2008, 21:52

Quote: (Originally Posted by Mossyback)

2. Ken, I just had a look inside the CL and I think I understand what you're suggesting. The OP valve has the hose that re-routes the gas over your shoulder. By removing the hose, plugging the OP outlet and drilling holes in the small plastic "O" ringed cap, the exhausted gas is forced out through the OP plastic cap. I then machine the brass fitting and route my diluent gas flush through that opening and into the CL. Am I correct? BTW, it looks like you just taped a plug in the OP hole. I guess there's not much pressure differential involved is there?

Hank

Hi Hank-

You’ve got it. Dil is indeed routed thru the machined fitting. The inner hole of the fitting is threaded to accommodate whatever method you choose to plumb the dil- QD fitting of some sort or a permanent hose.

The only thing not obvious has to do w/ how the output hole of the OP valve is plugged. The plug is not just taped. I actually put a hollow plug OVER the stub onto which the old hose had been attached. I then secured the plug w/ a narrow worm clamp. I then covered the worm clamp w/ some of that ‘stretch-and-seal’ tape to prevent any chance of the worm clamp chafing a hole thru the inside of the bag. Bit of overkill, I know, especially since the pressure differential is from inside the bag to outside. What little differential there is would tend to hold a hollow plug ONTO the stub.

Ken

**Dave Sutton** · 19th February 2008, 00:01

Hank, quick and dirty?

Tee the line into the CL where you add 02 and add dil there too. It'll takie just a few minutes and do the job. One port can add as many gasses as you supply to that point.

Dave

.

Mossyback · 19th February 2008, 02:28

Thanks to everyone for all of the suggestions. Now I can relax a bit and figure out which method to use given my ever shortening time frame.

Hank

18th February 2008, 15:28	#1 (permalink)
Mossyback Custom Title Allowed! Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Mar 2007 Location: Southern Ontario, Canada Posts: 109	IDA-71 – It Works but … Although I’ve dived my “71” several times on O2, I just spent 1 + hours on the bottom of the pool using it as a mixed gas unit. It functioned just fine! The manual add with the 0.5L snubber work just fine. I used Dave Sutton’s design. The ppO2 set-up - again Dave and Mark Munro’s design worked perfectly. I did several switches from the loop to a bailout bottle and back again. No problems. When I got home I tore the rig down expecting to find some water inside. Not a drop! I zipped open the counterlung and it was dry. I removed both scrubbers and they also were dry. With only 20 days to go before our Bahamas trip, things are looking good but ……. I’ve got one problem to solve and I need input. I find the ADV very hard to reach to do a diluent flush. I’d like to add to the diluent side a similar set-up as I use to add O2. The LP feed off the diluent regulator goes into the CL and directly to the ADV, therefore I can’t inject directly into the bag from this line. The only other entry point directly into the CL is through the O2 feed. Will the following solution work? I can run a hose from a LP port on the Diluent reg., through a Clippard valve to a “T” fitting on the O2 line before it enters the CL. This would allow for a manual flush into the bag. Comments? Hank __________________ "Be the kind of person your dog thinks you are."
(Offline)

18th February 2008, 16:45	#3 (permalink)
jmhardingjr Son of a Sailor Current Rebreather/s: Other CCR Home Build Other Rebreather/s: Other CCR Home Build Join Date: Sep 2005 Location: . . . this one particular harbor . . . Posts: 201	Re: IDA-71 – It Works but … I've never dived an IDA-71 but Dave Sutton claimed that with the ADV modification he made (the plastic disc and plunger, Franken-Son Diluent Addition) allowed him to do a dil flush by rolling his head back to activate the ADV. Apparently, if the rig is sitting high enough on your back you can just look up lean you head back to push on the little external button he put on his rig. Just a thought. Jay __________________ ". . . the sea's in my veins, my tradition remains, I'm just glad I don't live in a trailer . . ."
(Offline)

18th February 2008, 18:33	#5 (permalink)
Mossyback Custom Title Allowed! Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Mar 2007 Location: Southern Ontario, Canada Posts: 109	Re: IDA-71 – It Works but … Hi Guys, Thanks for the quick feedback. 1. Jay, I can't do Dave's "button" solution because the Oxycheq wings that I'm using come up above the "71" at the top. I can reach the ADV but it's a real struggle. I guess I could replace the wings with some of a different design. 2. Ken, I just had a look inside the CL and I think I understand what you're sugggesting. The OP valve has the hose that re-routes the gas over your shoulder. By removing the hose, plugging the OP outlet and drilling holes in the small plastic "O" ringed cap, the exhausted gas is forced out through the OP plastic cap. I then machine the brass fitting and route my diluent gas flush through that opening and into the CL. Am I correct? BTW, it looks like you just taped a plug in the OP hole. I guess there's not much pressure differential involved is there? 3. Giovanni, It appears that you've managed to obtain very small diameter hoses for your gas supplies. Can you give me the diameter of them and the operating pressure? Can you get sufficient volume through them? Things are pretty crowded inside my case and It would help if I could reduce the hose size. Hank __________________ "Be the kind of person your dog thinks you are."
(Offline)

18th February 2008, 18:52	#7 (permalink)
jaap Normal people worry me Current Rebreather/s: Classic Kiss Other CCR RB80 / Clone Ray Other SCR Home Build Other Rebreather/s: Other CCR RB80 / Clone Ray Other SCR Home Build Join Date: Jun 2005 Location: Stockholm Sweden Posts: 473	Re: IDA-71 – It Works but … If you need ideas for other simple points to feed gas into the rig, how about adding a feed on you pO2-probe? Or via the filling caps to the scrubbers (a bit far from the cells if you want to do a dil/sensor drill). But do you really need a manual way of manually adding dil at this stage? How about dil flushing by activating the ADV blowing some gas out the nose or sticking the tounge in the mouthpice and exhaling around it out into the water? __________________ My initials: JAAP
(Offline)

19th February 2008, 00:01	#9 (permalink)
Dave Sutton Diveshop of Horrors Current Rebreather/s: Sport Kiss MK 15.X rEvo Other CCR Azimuth Home Build Other Rebreather/s: Evolution Megalodon rEvo Other CCR Azimuth Home Build Join Date: Jun 2006 Location: Narragansett, Rhode Island and Hackettstown, New Jersey Posts: 2,907	Re: IDA-71 – It Works but … Hank, quick and dirty? Tee the line into the CL where you add 02 and add dil there too. It'll takie just a few minutes and do the job. One port can add as many gasses as you supply to that point. Dave . __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com
(Offline)

19th February 2008, 02:28	#10 (permalink)
Mossyback Custom Title Allowed! Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Mar 2007 Location: Southern Ontario, Canada Posts: 109	Re: IDA-71 – It Works but … Thanks to everyone for all of the suggestions. Now I can relax a bit and figure out which method to use given my ever shortening time frame. Hank __________________ "Be the kind of person your dog thinks you are."
(Offline)

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