soon new sentinel diver

Pat413

Pat413

Member
Could not resist to order a second hand Sentinel in good as new condition & factory serviced. So after be proud owner of Ouroboros, I will soon be also a Sentinel diver.
I'm really courious. I dove the unit already last year, but never assemble or dissaemble it so far. I will post my exploits here.

Cheers,

P.
 
OK friends, I got the unit yesterday, make a dissasemble and reassemble. I was told it's easier than the Boris to set up , so far I cannot confirm.
To reach the O2 sensors the whole unit must be stripped down and to open the head all hoses must be taken off.
Now my question: how often do you guys open the head?

On my other units I allow the sensor to "breathe" fresh air between every dive, I cannot imagine doing this with the Sentinel.

So, any thoughts?

Cheers,

P.
 
Pat413 said:
OK friends, I got the unit yesterday, make a dissasemble and reassemble. I was told it's easier than the Boris to set up , so far I cannot confirm.
To reach the O2 sensors the whole unit must be stripped down and to open the head all hoses must be taken off.
Now my question: how often do you guys open the head?

On my other units I allow the sensor to "breathe" fresh air between every dive, I cannot imagine doing this with the Sentinel.

So, any thoughts?

Cheers,

P.
Click to expand...

Only take the head off to send it in:)

Hose off to allow sensors to breathe if thats your thing. Its a huge hole right in the head. I never bother. The sensor placement doesnt seem to be to affected by moisture on 2nd dive.

Sensors fairly easily taken out - remove scrubber, flow cone, 2 screws and the whole carriage comes out.

Now is the time to buy used sentinels at a cheap price.:beep:
 
Hi Chris.
Thanks for your comments. Actually I buyed one cheap, in new condition and factory serviced. The course will be done later in autumn but of course I want to make my own experience so far, not intendet to dive it until the course.

So it's not necessary to remove the head after every dive day, i will remove the hoses in between the dives to allow sensor the breathe.

As my unit cames without tanks, I wonder if I should get 2L or 3L tank on DIL side? I know 2L is enough, but if place is for 3L (and especially with BOV) why not... Just afraid that it will decrease the counterlung capacity. I'm big and have +- 9L lung capacity, reason why I have another unit for sale...

What would the experts suggest?
 
Pat413 said:
Hi Chris.

As my unit cames without tanks, I wonder if I should get 2L or 3L tank on DIL side? I know 2L is enough, but if place is for 3L (and especially with BOV) why not... Just afraid that it will decrease the counterlung capacity. I'm big and have +- 9L lung capacity, reason why I have another unit for sale...

What would the experts suggest?
Click to expand...

It is possible to dive it with a 3L on the DIL side but will negatively impact the WOB. Better to stick with the 2L tanks.
 
Pat413 said:
Hi Chris.
Thanks for your comments. Actually I buyed one cheap, in new condition and factory serviced. The course will be done later in autumn but of course I want to make my own experience so far, not intendet to dive it until the course.

So it's not necessary to remove the head after every dive day, i will remove the hoses in between the dives to allow sensor the breathe.

As my unit cames without tanks, I wonder if I should get 2L or 3L tank on DIL side? I know 2L is enough, but if place is for 3L (and especially with BOV) why not... Just afraid that it will decrease the counterlung capacity. I'm big and have +- 9L lung capacity, reason why I have another unit for sale...

What would the experts suggest?
Click to expand...

It is personal choice for the 3L DIL tank. I don't like it as it potentially causes an issue crimping the counter lung against the bolts that hold the weight trim pocket in place. If you are not careful, this could wear against the CL and in time cause a hole. If you are not careful placing the CL around the 3L tank, you can find yourself in an unhappy place...

2L DIL is perfectly fine for everything you will need. Considering you are only using the DIL for sanity breaths as you migrate to an offboard bail out, even large lungs should not present a problem.

Many people prefer the 3L tank though as a safety net. Can't disagree with their choice - it is whatever makes you comfortable. Personally, I use 2L for all kinds of diving.
 
Well yes that's what I thought. Best possible WOB is mandatory. Will think on it, but will surely get the 2L tank. Also will propably connect a QC6 connector to BOV and connect it directly to off board tank. I have plenty off time to make the unit how I want it to be.
Thanks for responses. Cheers, P.
 
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I would also add that the sentinel design & philosophy lends itself to off board gas addition. It seems to me that you are intended to dive with 2 lyrics tanks and simply feed the solenoid or adv with off board gas when you get low.

The software and swagelok hardware support this approach.

Just like your Boris no?
 
I dive the Sentinel with 2L tanks. The off bard set up is nice a bit large (like the Sentinel itself) but works great. Congrats on the purchase and have fun with it.
The O2 cell placement is designed to not build up excessive moisture on the cells. I let them dry out with the scrubber cartridge out at night.
 
Hi,
I dive the 2 litres and have no need to go bigger ,, on planned exbidition dives I would use the off boards and keep the 2 litres as normal ,
As for taking of the head , nightly I too air the canister with the scrubber out and co2 monitor out and hoses off but if you read the manual it will tell you to take the head off after every 20 hrs use to clean contacts on o2cell block and clean behind cone as part of you upkeep maintenance , if poss it is a good idea to do the service course with vr ,I did and it gives you a great knowledge of your unit not only for looking after but for how you use it to its potential in water too :)


Thanks BJ
 
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Actually, I had no use for off board so far with Boris. My Sentinel has no off board connectors and there is no intend to fit them in near future. Just QC6 for BOV, so I can choose if I connect IN or OFF BOARD.

Well, I have to admit that on first strip down I was confused, but now I get confident and I really want to dive the unit asap... Cant wait for the course.

BTW, how do you check if the scrubber really fits on CO2 seal? I understand that it locks with the springs when closing the bottom. Want to be sure that it seal 100% and want to check it, but how??
Thanks again.
 
Pat413 said:
Actually, I had no use for off board so far with Boris. My Sentinel has no off board connectors and there is no intend to fit them in near future. Just QC6 for BOV, so I can choose if I connect IN or OFF BOARD.

Well, I have to admit that on first strip down I was confused, but now I get confident and I really want to dive the unit asap... Cant wait for the course.

BTW, how do you check if the scrubber really fits on CO2 seal? I understand that it locks with the springs when closing the bottom. Want to be sure that it seal 100% and want to check it, but how??
Thanks again.
Click to expand...

negative pressure test and the co2 readings after pre breathe. You can see it all in the predive checks.

Ive found the co2 sensor extremely accurate when correctly calibrated. You will see any c02 in the loop and just like on units without the sensor, the pre breathe should show any co2 bypass (hopefully:))
 
OK, but I have a pre-Optocom unit without CO2 sensor... I want avoid headache while pre-breathing hehe.
 
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When you put the canister in and close it, shine a torch down into the ports, look for any kinks etc in the seal. Otherwise, a five minute pre breath should identify to you if you have not put it together right.

Good luck.

Karl
 
+1 for both Chris and Karl's advice plus after you've done it a couple of times you'll get to recognise the feel and sound as you twist the bottom shut and the scrubber locates :) ,,,,,,,, sounds abit rude now I read back :)


Thanks BJ
 
Ok, thanks alot for these precious advises.

One more thing: one the O2 side my unit has M26x2 nitrox thread (I think for the CE it's mandatory). Do you guys uses adapter while being up road with other tanks or did you modify the 1. Stage to 5/8 DIN?
 
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