apeks fsr vs dst first stages

[rick00001967]

i understand the xtx50/100/and 200 second stages are the same. but i would like some opinions on the fsr vs the dst first stages.
i am debating between the xtx50 w/dst and xtx200 w/fsr

i would love to hear pros and cons of each. for the sake of this discussion lets assume that cost is not a factor as we know the xtx200 is more expensive

my one concern at this point is that the fsr soft seal is on top. if i turn it upside down to protect it in overhead environments (wreck, ice, or cavern etc) the hose routing is not great because of the shape. the dst has that seal on the bottom. btw....icurrently dive single back mount with a slung pony. i would love to upgrade to double sidemount one day but who knows.
thx
rick

 

[buddhasummer]

FST has the diaphragm on the bottom. DST has a swivel turret. FSR has a removable HP crown, none of the others do. Even if by some remote chance managed to hit and tear the diaphragm the reg would still function. I'm not sure in reality how much of a concern this actually is but then I don't dive wrecks or overhead environments. But IMO I think a non issue. I only single tank dive and like the hose routing of the FSR.

 

[Colliam7]

i am debating between the xtx50 w/dst and xtx200 w/fsr . . . i would love to hear pros and cons of each. for the sake of this discussion lets assume that cost is not a factor as we know the xtx200 is more expensive . . . my one concern at this point is that the fsr soft seal is on top. if i turn it upside down to protect it in overhead environments (wreck, ice, or cavern etc) the hose routing is not great because of the shape. the dst has that seal on the bottom.

Three comments / questions:

1. I am not sure exactly what you find to be problematic with the hose routing when the FSR first stage is inverted (although I presume it is the relative position of the HP hose and the LP inflator hose). So, I may miss the mark with my comment. But, I have used a FSR inverted and it does work. However, is that what you mean by your comment - the HP hose is now above the LP hose and sticks up and out a bit?

2. Have you considered going with a FST first stage instead of the FSR?

btw....icurrently dive single back mount with a slung pony. i would love to upgrade to double sidemount one day but who knows.

3. I don't find that a turret is particularly useful for single cylinder backmount diving. There really isn't anything wrong with it, I just don't see any real advantage (a Zeagle 50D was my first reg and my primary recreational reg for 10 years). So, on that basis, I would say the DST, although a fine first stage, is not a necessary direction to choose. HOWEVER, if you believe there is a genuine possibility of configuring for sidemount in the not too distant future, and the DST would be one of the two first stages in a SM rig, then I am a strong advocate. I particularly like turrets for SM, for any number of reasons. One of my SM reg sets is a pair of DST first stages (the other sets are pairs of the very similar Zeagle 50Ds) and I really like the regs for that use.

 

[rick00001967]

buddha....i of course am not a reg technician but had been told to protect the seal by more than one instructor. i just assumed the 1st stage would be contaminated if it was damaged during a dive. and if i was in extremely silty or cold conditions, this contamination could cause a 1st stage failure. so am i incorrect in this assumption ??

---------- Post added December 17th, 2013 at 02:03 PM ----------

colliam....
1 - you are correct about me concern with the hose routing. because of the angle, the hp hose sticks up and out. not the end of the world but not ideal.
2 - no. i have never seen an fst
3 - i would love to switch to double side mount but who knows if i will ever be able to do that.

i guess because i am not a technical expert on regs, i am asking opinions to hear any concerns between the two as far as performance, quality, etc
i know the xtx200 is considered by most apeks users as the cream of the crop. and i do love mine. but is there really any noticeable difference when using them or maintaining them etc. is the dst a big step down for any reason

 

[Fishpie]

As BH says there's nothing under that outer seal that doesn't get exposed to water in the unsealed version of the 1st stage.
The dry enviro seal has a 2nd diaphragm under the outer one.

 

[rick00001967]

so the outer one is decorative and the one under is the diaphragm that is important to the regs operation ?? so you would have to puncture both to cause any problem ?? so what would happen (even if unlikely) if both were damaged in a way that let water/contaminants into the 1st stage ??

 

[Fishpie]

The outer seal is there to prevent water freezing around the main spring in very very cold water.
It would be almost impossible to puncture the inner diaphragm......without disassembling the 1st stage, removing the spring and pressure plate and then poking a knife or ice pick in the hole.

 

[rick00001967]

The outer seal is there to prevent water freezing around the main spring in very very cold water.
It would be almost impossible to puncture the inner diaphragm......without disassembling the 1st stage, removing the spring and pressure plate and then poking a knife or ice pick in the hole.

so you sound like you are essentially confirming my initial belief. if that outer seal fails (for whatever reason) water will enter a section of the 1st stage. and if it freezes that section the reg could fail. or am i misunderstanding ??

 

[Fishpie]

If the outer seal is punctured the reg will now be the non environmentally sealed version of that 1st stage.
However by their very design diaphragm regs are very resistant to freezing.

What you are worrying about is a puncture in the outer diaphragm leading to the middle chamber getting completely filled with water and then being in water cold enough for it to then freeze and cause the main spring to be unable to flex.......yes, theoretically that could happen.....

 

[Centrals]

Apeks also produce regs without the outer diaphragm eg. US1, US4 and UST for scuba diving. These three regs are NOT for cold water diving ie. below 10C.
This outer diaphragm is officially(Apeks) known as hydrostatic diaphragm. It has other function other than just keep the water out from the BIG spring. have read at Apeks home page.
FSR is the one that I would prefer because of the replaceable HP crown seat. The rest of its stable mates are NOT that lucky. But I have diving with a DS4 well over 15yrs and is still going strong.
Look after it properly and Apeks reg would really last a long time.
Self service is not difficult at all.