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I am in the process of learning to DIY and understanding the subtleties involved.
At present I have so many different kinds of regs it"s hurting my head and wallet. I've been mostly successful in servicing them all.
I'm considering culling to basically one type of first stage and one type, save D300, of second stage for my usual regular diving.
I've spent a lot of time mulling this over, taking all things into consideration, ease of bteathing, the depths I dive, water temps, ease of self servicing in remote locations, tools required, ease of obtaining parts etc. I think Apeks first stages with G250 secconds fit all my criteria.
I'm aware that Apeks are "overbalanced" and one can expect an increase of ip of around 1.5psi for every 10 meters of depth. My max depth is most often around 40 meters, occasionally, now I have a child, a fraction deeper.
I understand a G250 will start to freeflow at an increase in ip of around 5psi if tuned just shy of freeflow.
An Apeks first stage ip increases about 3-5 psi at low tank pressure. At 40 meters an ip increase of around 6 psi can be expected due to its overbalancing "feature".
That being said, I'm wondering the best way to tune the G250s to ensure no freeflow at depth.
As I understand it I can go several different routes:
A) tune the second stage to 1.2" as apparently this increases the point at which they are likely to freeflow from around 5psi to 20-25psi.
B) Do nothing and just use adjuster if/when required.
Or...
C) My thought, set the second stage just shy of freeflow at 145psi but use it with first stage tuned to 140psi as this will give me the required room to hopefully prevent any free flowing at depth. I can ignore the 3-5psi increase relating to low tank pressure as I'd never be at depth with only 500psi in the tank.
I'm wondering which course, if any, would give me the best performance throughout the dive or if basically any of the options would net the same result.
I'm ok about trying each option myself but thought if any of the gurus could advise it would save me some time.
If my understanding is wonky I'm of course happy to be corrected.
I know I can get a tank and play and probably get my answer but also wanted to check my understanding or lack of.
Thank you.
At present I have so many different kinds of regs it"s hurting my head and wallet. I've been mostly successful in servicing them all.
I'm considering culling to basically one type of first stage and one type, save D300, of second stage for my usual regular diving.
I've spent a lot of time mulling this over, taking all things into consideration, ease of bteathing, the depths I dive, water temps, ease of self servicing in remote locations, tools required, ease of obtaining parts etc. I think Apeks first stages with G250 secconds fit all my criteria.
I'm aware that Apeks are "overbalanced" and one can expect an increase of ip of around 1.5psi for every 10 meters of depth. My max depth is most often around 40 meters, occasionally, now I have a child, a fraction deeper.
I understand a G250 will start to freeflow at an increase in ip of around 5psi if tuned just shy of freeflow.
An Apeks first stage ip increases about 3-5 psi at low tank pressure. At 40 meters an ip increase of around 6 psi can be expected due to its overbalancing "feature".
That being said, I'm wondering the best way to tune the G250s to ensure no freeflow at depth.
As I understand it I can go several different routes:
A) tune the second stage to 1.2" as apparently this increases the point at which they are likely to freeflow from around 5psi to 20-25psi.
B) Do nothing and just use adjuster if/when required.
Or...
C) My thought, set the second stage just shy of freeflow at 145psi but use it with first stage tuned to 140psi as this will give me the required room to hopefully prevent any free flowing at depth. I can ignore the 3-5psi increase relating to low tank pressure as I'd never be at depth with only 500psi in the tank.
I'm wondering which course, if any, would give me the best performance throughout the dive or if basically any of the options would net the same result.
I'm ok about trying each option myself but thought if any of the gurus could advise it would save me some time.
If my understanding is wonky I'm of course happy to be corrected.
I know I can get a tank and play and probably get my answer but also wanted to check my understanding or lack of.
Thank you.
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