IDA-71 MOD and time

divingtoors

HI there

Eventually my converted IDA-71 is in the testing phase.
Testing is done by using it as a O2 CCR to iron out some minor changes and hicups that needs to be taken care of
Hopefully to take it to deeper depths in the very near future.

What is the deepest and longest dives you have done with your KISS converted IDA-71's, with both scrubbers and all the other bells and whistles installed.

How did the unit perform at these max depths and times?
Any further advise and "tips" on improving the unit's performance

regards

Johan

Corallaro

Hello

my IDA 71 has arrived :-)

and, i also quote the questions of Johan

I thought to make these modifications to make it a modular system how Dave Sutton teach:

1) remove oxygen internal tank and replace with that of offboard nitrox unit (removed of switch unit) to fill with diluent.

2) use quick-disconnect of offboard nitrox unit to insert a biggest diluent tank for impegnative dive, drysuit, wings, bailout.

3) in the space of communcation system (under the scrubbers) put the oxygen tank with first stage closed using a modified cover of first stage of nitox tank, with a kiss style injection

and now other question:

without removing the quick-disconnect system wich is the biggesta tank that i fill in this space?


Giovanni



PS
obviously............triple sensor display,weight near counterlung,,, ecc

Dave Sutton

Tiny. Far too small to be of value.

Even after the quick diconnect is removed, that area is really too small to do anything good with. You need space for running hoses, etc., and in my experience it is best left alone for this reason.

My suggestion is to simply use 2 scrubbers, use an oxygen cylinbder where the existing one now sits, and to carry all of your diluent offboard. Feed it wiht a quick disconnect hose. You can choose the size of the cylinder for the depth you dive.

If you really wish to carry 2 gas suplies internally, use the smaller one for diuent. If you do choose to put a small cylinder across the bottom I would choose that for diluent supply. You use diluent once: On descent. You use 02 constantly. If you do not allow mask leaks of gas, you will use less diluent than 02.

Dave

__________________
"Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com

Dave Sutton

180 feet for 90 minute run times including deco.

Performance was just fine.

WOB is *greatly* inproved by use of good breathing hoses and DSV (Draeger Ray works best). The brass DSV is cool, but it works like junk deep. Lots of restriction.

Use both scrubbers deeper than about 75 feet. I had a C02 hit at 130 feet on a single scrubber version. I recovered after a minute of rest, but it was a good lesson.

Make the system modular so you can use internal diluent and one scrubber shallow and dual scrubbers and external diluent deep.

I'm sure you have read my pages on the mods I made, many small bits of information there.

You MUST redo the internal counterlung hose connections to the "Y" that feeds gas into the scrubbers. They have become undone and lead to scrubber bypass. We "almost" lost a diver here because of that. I jumped into the water off the boat 30 miles ofshore and rescued him. He was *totally* incapacitated by the C02 and was unable to even remove his DSV and breathe surface air. This was a surface swimming incident, after he entered the water but bfore he made it to the anchor line for descent. It scared us LOTS. I swam clothes and all...


Any other specific questions will be answered with pleasure. With all due respect to the other rigs, there are two rigs now with perfect safety records: The KISS (CK and SK) and the modified IDA-71's. I estimate that there are well over 100 being dived right now, and other than the (quickly learned) internal counterlung inspection/fix issue, there have been no problems at all with any of them. Nobody has gotten hurt on one (so far at least), and that's a good record.

As the primary proponent of these rigs worldwide, and the spiritual father of the Franken-Rig/Franken-Son series, I'm pretty proud of the rig and what has been done with it. Do a nice job on it!

Dave

__________________
"Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com

lilou

Hi,

I dove mine at about 220 feet for about 100' including deco more than one time and it works well with only one scrubber. For these type of dive i dive only with fresh sorb and that's it, the scrubber design is very good on the ida.

Best regards

Lilian

montyg

Hi Dave, others

We have been lucky here in SA since all four IDA-71's came with very sturdy metal clamps on all three sides of the T-piece on the exhalation side going through the counterlung.

There's some other minor differences between our IDA's and your one on the website, like we don't have the "bridges" across the holes in the case. We have to cut away part of the case or undo hoses to re-route them where they go through the holes in the case.

rgds
monty

Corallaro

Hi

i see beter my IDA71 but all documents write 1 liter tank oxygen (internal) and 1 liter tank nitox 40 (external unit) but is obvious that the two tanks have different size, the external nitrox tank is bigger....

can you tell me the exat volume.....i don't uderstant what is written on the tanks

Giovanni

montyg

FWIW, my off-board nitrox tank is 1.5 liters, but some of my buddies' IDA's also only has 1 liter tanks.

Perhaps it depends if the IDA was intended for use in the Navy or the Air Force?

rgds
monty

Corallaro

Thanks monty

your answer is an answer for all my questions....for the moment :-)

so my off-board nitrox tank is 1.5 liters.

i have replaced the internal 1 liter oxygen tank with the 1.5 off-board nitrox tank, fill it with diluent, replacing some parts (gauge and HP T-fitting)

and for the momet i use a 1 liter tank with the "classic" RGU-FM oxygen unit.

now the next is an 1.5 liters oxygen tank that is the maximum tank size to put in the space under scrubbers to make an "all in" unit with two scrubbers.

regs

Giovanni

Dave Sutton

IDA cylinders come in several versions:

(1): Internal 02 bottles:

a: Carbon Steel 1 litre.
b: Inconel wound with wire 1 litre.


(2): External nitrox bottles:

a:Carbon steel 1 litre (round bottom).
b:Carbon steel 1.5 litre (round bottom).
c:Aluminum 1.5 litre (flat bottom)


If you can squeeze (2) 1.5 litre bottles into the chassis, then you are doing great. You WILL need to add 5 KG of lead to the inside of the lid at the top as it will balance head-up for sure.


Are you using the RGU regulator attached directly to the cylinder (as my original Franken-Rig) or at the end of a feed hose so you can wear it on your chest D-ring? We did that last on a few rigs and it worked nice, made more space in the rig, and with an extra port at the adapter we placed a HP contents gauge at that point too.

Dave

__________________
"Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com