Hog wrapping a bail out hose under a loop on a rebreather.

[PfcAJ]

For the benefit of non chest-mounted Optima people and the majority who’ve never seen one in the flesh…

As a chest mounted box, i.e. on the front, not back or sides, will the loop hoses always be in front and thus — should someone backmount a twinset with longhose and necklace hung backup — the longhose won’t be trapped?


BTW how many RB80 semi-closed range extender were made?

actual RB80 from halcyon is probably sub 300.

But there’s a bajillion clones and rb80-ish pSCR units out there (like the tres presidents).

 

[lostsheep]

We're not gonna flame you for experimenting or showing what you're trying.

To be clear, that wasn’t specifically directed at SB; I’ve deserved a lot of flaming for the dumb ideas I’ve posted on various forums over the years. Trust me, I have no shortage of bad ideas

As a chest mounted box, i.e. on the front, not back or sides, will the loop hoses always be in front and thus — should someone backmount a twinset with longhose and necklace hung backup — the longhose won’t be trapped?

Correct.

 

[Wibble]

actual RB80 from halcyon is probably sub 300.

But there’s a bajillion clones and rb80-ish pSCR units out there (like the tres presidents).

(pSCR?)

Semi-closed rebreathers aren’t exactly mainstream technology when compared with the hundreds of thousands(?) of full CCR being used. There’s one or two benefits of SCR, such as not needing high pressure oxygen, but at the cost of all the drawbacks of CCR without the benefits.

One expects that more Hollis ‘Stormtrooper' units were made than RB80s?

Would anyone with a choice of using a CCR really choose an RB80 over using a CCR? Even GUE have dropped the RB80 in favour of their heavily modified JJ.

 

[Wibble]

And its still a stupid idea which continues to be propagated even by some "big names" which as the trimix thread elaborates on, aren't necessarily any good. One of the worst CCR and cave instructors in the entire SE USA has written numerous books and gets tons of speaking engagements. Their students reliably come out of class with terrible habits and skills.

In who's humble opinion?

Every class one completes, especially foundation classes, one needs to do a *lot* of post-course practice to consolidate and improve one's skills. Those foundation classes -- ANDP, MOD1, intro to cave -- all require the student to have good core skills.

If a student with borderline core skills does a course such as those above and does enough to get a "pass", should they actually be failed because they should have got a "good" or "great" or "excellent" pass?


Must do a to GUE for their Fundimentals course. Strange that they're still the only agency that values core skills to that level. Enter a foundation-level class with rock-solid core skills and quelle surprise the student has a much better chance of not only passing but passing with flying colours.

 

[lermontov]

In who's humble opinion?

Every class one completes, especially foundation classes, one needs to do a *lot* of post-course practice to consolidate and improve one's skills. Those foundation classes -- ANDP, MOD1, intro to cave -- all require the student to have good core skills.

If a student with borderline core skills does a course such as those above and does enough to get a "pass", should they actually be failed because they should have got a "good" or "great" or "excellent" pass?


Must do a to GUE for their Fundimentals course. Strange that they're still the only agency that values core skills to that level. Enter a foundation-level class with rock-solid core skills and quelle surprise the student has a much better chance of not only passing but passing with flying colours.

I think youve missed the point - which is: having your 3 -4 litre dil bottle as your BO gas is a bad idea -theres no mention of core skills in the post. What is under scrutiny is why would you have a small bottle of gas that is ( presumably ) suppplying fresh diluent - your wing and now a BOV .

add some anxiety and maybe a bit of narcosis in a BO situation (god help you if its co2) and youd drink though a 3 litre of gas at 60m in a veeeery short time - Next problem- possible wing and dil issues and youve got the very thing ( I thought ) were all trying to mitigate i.e. cascading issues that get out of control

 

[Wibble]

I think youve missed the point - which is: having your 3 -4 litre dil bottle as your BO gas is a bad idea -

That's not what I said -- about people coming out of classes with bad skills.

---

To answer the BOV connected to a small diluent, not to the bottom bailout, that's the challenge with BOVs and why many people consider BOVs to be way too complex and more trouble than they're worth.

The use case for connecting them to small diluent bottles is for "sanity breath" only, which isn't good when deep.

 

[rddvet]

No matter how big the name is or how cool of dives that person does, attaching your bov to a 3liter is just stupid.

 

[PfcAJ]

(pSCR?)

Semi-closed rebreathers aren’t exactly mainstream technology when compared with the hundreds of thousands(?) of full CCR being used. There’s one or two benefits of SCR, such as not needing high pressure oxygen, but at the cost of all the drawbacks of CCR without the benefits.

One expects that more Hollis ‘Stormtrooper' units were made than RB80s?

Would anyone with a choice of using a CCR really choose an RB80 over using a CCR? Even GUE have dropped the RB80 in favour of their heavily modified JJ.

I’m not really concerned with what’s “mainstream”. Mainstream scuba is a race to the bottom.

SCR is absolutely fantastic for long range cave diving. The reliability and simplicity is not even comparable.

The Hollis thing was marketed toward rec divers.

GUE continues to teach RB80. There are more RB80 instructors now than there have ever been. One would choose it over CCR if they’re doing long range cave diving.

 

[ginti]

GUE continues to teach RB80. There are more RB80 instructors now than there have ever been. One would choose it over CCR if they’re doing long range cave diving.

Five instructors, actually, but maybe more than in the past
GUE Instructors

I have heard that the PSCR is way better for long-range cave diving, and I have also heard that the JJ is the perfect machine for deep-sea exploration. I understood only one advantage of the RB80 over the JJ. When there is no oxygen, you immediately can detect it because of the different noise when you breathe (did I understand correctly?). But I do not know what other advantages it could have specifically for caves. Could you explain? Thanks

 

[PfcAJ]

Five instructors, actually, but maybe more than in the past
GUE Instructors

I have heard that the PSCR is way better for long-range cave diving, and I have also heard that the JJ is the perfect machine for deep-sea exploration. I understood only one advantage of the RB80 over the JJ. When there is no oxygen, you immediately can detect it because of the different noise when you breathe (did I understand correctly?). But I do not know what other advantages it could have specifically for caves. Could you explain? Thanks

Back a few years ago it was just Jarrod and DRhea.

So the big advantage is reliability. The thing just WORKS. Every time. It’s ridiculously simple. No sensors. No solenoid. No MAV. Just two r190 injectors. There’s nothing to really monitor. If you can breathe and it burps some bubbles every now and again, it works. Reliability matters when you’ve put a tremendous amount of time into a dive with a ton of support poured into it.