Hammerhead CCR Web Pages Up

silent running · 21st December 2007, 04:51

Quote: (Originally Posted by caveseeker7)

Andy, I'm with Joe on that one, the PRISM scrubber isn't very flood tolerant. It's a simple matter of math, the center tube doesn't have much volume, certainly less than spacers used on the bottom of many scrubber generate. In the PRISM's bucket that space is used to accumulate condensation, not act as a water trap. Nor does the PRISM's design allow for a drain valve just before the scrubber, as the Sentinel has and many units could have.

The PRISM's counterlungs work very well as water traps and allow water to be purged. That may make up for the most common reason for water in the bag, bad mouthpiece protocol, but it doesn't help much if water gets into the loop past it (most likely at the exhalation hose to head connector, or the hose itself).

Hi Stefan, I'm sure the out-in flood tolerance is better, but it seems very unlikely that so much water would enter the head/scrubber bucket. Even if a hose from the head to the CL was punctured, I think it would more likely flow down into the CLs before going into the stack, which in a normal dive position would be above the CLs. And even if a large amount of water did make it down the tube, one could always change position and move it back into the CLs by going heads down, rolling and then getting rid of excess through the CL drains-Prism-or through the man add valves-Inspo/Meg.

But I'm still wondering if the lower inlet scrubber temp of a unit with an out-in flow would be more likely to cause a CO2 hit from over breathing during a period of high exertion at the beginning of a dive. I think of all the exploratory dives I've done which have started out in less than calm conditions so I'm sure it's not unusual for somebody to experience a period of high stress/exertion at the beginning of a dive in a new environment.

The other obvious trade off of an out-in flow is the excess condensate that collects in the sensor area. In an in-out flow the condensate collects on the cooler bucket wall, away from the sensors. There's already 100% humidity in the loop without concentrating more moisture near the sensors. This seems like a definite drawback to me.

The HH looks like a top notch CCR with many good design features and excellent tooling. But I'm just not sure the in-out flow trade off is worth it.

I would be interested to hear any of Kevin's thinking and annecdotal evidence of the benefits of the out-in trade off...

***jradomski*** · 21st December 2007, 05:45

Quote: (Originally Posted by silent running)

But I'm still wondering if the lower inlet scrubber temp of a unit with an out-in flow would be more likely to cause a CO2 hit from over breathing during a period of high exertion at the beginning of a dive. I think of all the exploratory dives I've done which have started out in less than calm conditions so I'm sure it's not unusual for somebody to experience a period of high stress/exertion at the beginning of a dive in a new environment.

...

How fast is really a function of scrubber dimensions.. If they are sufficient and mosture is available the scrubber should be able to cope pretty rapidly.. The golem scrubber has about 25% more sorb (theorfor contact surface area) than a scrubber the size of the standard prism, and therofoe has the potential to startup even faster.. dimensions are more important that direction.. poor dimensions and the direction doesnt matter.. Look at the difference between the original prism scrubber and the released one, just a small difference in sorb made a BIG difference because the dimensions changed..

Hot gas VS cokd gas towards the sensors doesnt really matter.. what matters is WHERE there is a cooler surface if the gas is still hot, it will contain the same amount of moisture, you wount get condensation until there is a temperature drop.. on the HH the cell faces are VERY close to the exited gas (and a small volume as well) so its unlikely alot of moisture will build on the cell faces.. They are also pointing down (when vertical) so even moisture does end up on the cell it would move off the face in the prone position.. The cooling will be further up the head and then it would run down the tube away from the sensors.. Also remember this since the outlet side of the loop is hotter than the inlet side its capable of holding more moisture..

silent running · 21st December 2007, 06:47

Quote: (Originally Posted by jradomski)

How fast is really a function of scrubber dimensions.. If they are sufficient and mosture is available the scrubber should be able to cope pretty rapidly.. The golem scrubber has about 25% more sorb (theorfor contact surface area) than a scrubber the size of the standard prism, and therofoe has the potential to startup even faster.. dimensions are more important that direction.. poor dimensions and the direction doesnt matter.. Look at the difference between the original prism scrubber and the released one, just a small difference in sorb made a BIG difference because the dimensions changed..

Hot gas VS cokd gas towards the sensors doesnt really matter.. what matters is WHERE there is a cooler surface if the gas is still hot, it will contain the same amount of moisture, you wount get condensation until there is a temperature drop.. on the HH the cell faces are VERY close to the exited gas (and a small volume as well) so its unlikely alot of moisture will build on the cell faces.. They are also pointing down (when vertical) so even moisture does end up on the cell it would move off the face in the prone position.. The cooling will be further up the head and then it would run down the tube away from the sensors.. Also remember this since the outlet side of the loop is hotter than the inlet side its capable of holding more moisture..

OK Joe, your point about the differences in duration btw the 5.5 and 6lb Prism scrubber are well taken and maybe you're right about the larger proportions/reaction front of the Golem radial making up for the initial inlet temp being lower than an in-out flow. But I could also imagine that a large volume of scrubber material might take longer to reach an optimal temp for the reaction to function efficiently, no matter where the heat comes from. After all, it does take more energy to heat 1 cubic yard of sand to 100F than 1 cubic foot, right?

And if flood tolerance is the big concern in the HH design why not also have a drain in the bottom of the scrubber bucket?

As for the condensation issue, I can't imagine that having a bunch of condensate forming on surface of the inner tube of an out-in flow scrubber is very good for WOB as it would likely cause the sorb to swell and increase gas flow resistance. Where does the extra moisture go, to the bottom of the scrubber? This could create a similar effect to a flood of an in-out radial, not to mention causing a decrease in the performance of the sorb as the reaction front reaches moisture saturated sorb at the end of the scrubber duration. I'm aware that radial breakthrough is supposed to be more sudden than a simple tube tube axial but, I would guess that the 2 flow directions are not equal in their breakthrough speed. My guess is that an in-out radial has slower breakthrough than out-in due to the increasing size of the reaction front and less clumping due to the condensate clinging to the scrubber bucket wall.

I'm happy to chaulk it all up to pros/cons, but I would like to know more about the choices made in the HH design...

***jradomski*** · 21st December 2007, 08:12

Quote: (Originally Posted by silent running)

And if flood tolerance is the big concern in the HH design why not also have a drain in the bottom of the scrubber bucket?

.

No need.. You can trap ALOT of water at the bottom of the bucket.. The normal spacer is at least 2 inches (I never measured it) by over 6 inches in diameter...

If my rough approximations are correct thats about 1 l of volume..

***caveseeker7*** · 21st December 2007, 08:55

Andy, while I understand and support your thirst knowledge and understanding of scrubber designs there are but few people that can impart it. Else we all would have excellent scrubber designs.

More importantly is probably the question "does it really matter?"
The pros and cons of the two opposite flow directions have been pointed out pretty well I think. The PRISM has them. The Hammerhead has them. Either way I'm sure you're getting one of the more capable canisters out there, with a lot of absorbing capacity. One has around 6 lbs capacity, the other 7.5 lbs. Which one would be more efficient had they the same capacity might be of intellectual interest, but IMHO doesn't matter as they don't.

More important is their duration, rather than how they got there. For the PRISM that's fairly well known as SMI has released some testing data, though more is needed I believe. At CE standards for one thing, to be able to a fair comparison, and for more than 60 ft at that.

The Golem scrubber is being tested as Jakub posted, and I hope those tests are done to the general CE protocol, with data for 40 m (plenty of comparable data thanks to Kevin Gurr) and 100 m (available for Inspo, Evo and Ouroboros).

The same, really, goes for just about everything else. For an exploration level rebreather flood tolerance or ability to drain the loop are good features to have, even a small, slow leak can add up if you have 5, 8, 10 hrs of deco to worry about.

You look at the rig, you look at the features, and you choose what suits you.
Anyone with an Optima watching you pack your scrubber with the factory recommended Sodasorb will probably say "No friggin' way". You'll take one look at them changing batteries on their secondaries and say the same.

I have no problem with the Hammerhead's scrubber, other than that it's way bigger than what I need. The cell placement issue is different though, I doubt I could get comfortable with that. But that's just me, couple o'hundred Meg divers don't seem to be bothered by it. Same as the lack of an independent pO2 gauge on the AP units. It's a problem for me, several thousand owners don't have it ... shame really, John and Beanie should get rich fixing it.

Talisman · 26th January 2008, 18:37

Is this unit going to be at BTS or Sea Rovers?

***diverklondike*** · 27th January 2008, 01:45

Quote: (Originally Posted by Talisman)

Is this unit going to be at BTS or Sea Rovers?

Yes to BTS... Not sure if Kevin will have a booth or not but he always comes to the show. Regardless I will be there and am happy to bring my rig.

I know that Kevin will not be at Sea Rovers. I may but will not bringing a rig.

I will however be doing a CCR presentation next Saturday at Northeast Scuba in PA and will have my HH CCR with me.

Send a PM if you want more details.

Dive Safe

Mark

cameron · 5th February 2008, 16:01

Any word on the BMCL for the unit? Any pictures?

Cam

Draggs · 6th March 2008, 11:24

Hi I have read your info on the hammerhead and it looks to be an awesome piece of technology but there is a few questions like how deap can it go, what does the rig come with like harness etc, as I live in australia how would i go about training for the rig. I am new to all this and just want to buy the best there is for what I want to do with it. I am finishing my open circuit deco tec diving courses and extended range is also on my list of things to do I love the deep oceon and just want to explore what it has to offer. It would be getting used as much as I have time to get into the water want to get into trimix and go deep looking to maybe get to 100metres in a couple of years been diving open circuit for 8 years now and want to move forward and am just really keen to reap the benafits of a rebreather. If you could please help me out with some great ideas and obviously highly experinced advice on towhich rebreather would perhaps be my best option it would be great.
Many thanks
Draggs

jont · 7th April 2008, 13:30

Draggs:

You can't go wrong with a Hammerhead Rebreather, I have some experience with a number of units and the Hammerhead will in all likelyhood me the next purchase I make, but i'd like to make several sugestions:

1) When it comes to life support equipment NEVER let money (or lack of it) make decisions for you.
2) Look atfeel and try and dive as many units as possible.
3) There are huge differences in quality of construction so understand them.
4) If anyone is giving you the "used car" sales pitch....just stay away as you would.
5) Its important to understand the difference between the various types of Rebreather's out there

About the hammerhead there's allot to like: great electronics, very well built (if not the best in that category), huge scrubber, very versatile (depth is really not an issue) CMF ability, the buisness that makes them gives new meaning to the term "customer service" they are the best.

The one complaint I have heard (sensor issue) is not as big of a deal as its being made out to be (on THIS unit), but its being handled.

Other units to look at are:
Meg.
Kiss
Revo
Boris

Hope this helps,

J

21st December 2007, 04:51	#21 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,780	Re: Hammerhead CCR Web Pages Up Quote: (Originally Posted by caveseeker7) Andy, I'm with Joe on that one, the PRISM scrubber isn't very flood tolerant. It's a simple matter of math, the center tube doesn't have much volume, certainly less than spacers used on the bottom of many scrubber generate. In the PRISM's bucket that space is used to accumulate condensation, not act as a water trap. Nor does the PRISM's design allow for a drain valve just before the scrubber, as the Sentinel has and many units could have. The PRISM's counterlungs work very well as water traps and allow water to be purged. That may make up for the most common reason for water in the bag, bad mouthpiece protocol, but it doesn't help much if water gets into the loop past it (most likely at the exhalation hose to head connector, or the hose itself). Hi Stefan, I'm sure the out-in flood tolerance is better, but it seems very unlikely that so much water would enter the head/scrubber bucket. Even if a hose from the head to the CL was punctured, I think it would more likely flow down into the CLs before going into the stack, which in a normal dive position would be above the CLs. And even if a large amount of water did make it down the tube, one could always change position and move it back into the CLs by going heads down, rolling and then getting rid of excess through the CL drains-Prism-or through the man add valves-Inspo/Meg. But I'm still wondering if the lower inlet scrubber temp of a unit with an out-in flow would be more likely to cause a CO2 hit from over breathing during a period of high exertion at the beginning of a dive. I think of all the exploratory dives I've done which have started out in less than calm conditions so I'm sure it's not unusual for somebody to experience a period of high stress/exertion at the beginning of a dive in a new environment. The other obvious trade off of an out-in flow is the excess condensate that collects in the sensor area. In an in-out flow the condensate collects on the cooler bucket wall, away from the sensors. There's already 100% humidity in the loop without concentrating more moisture near the sensors. This seems like a definite drawback to me. The HH looks like a top notch CCR with many good design features and excellent tooling. But I'm just not sure the in-out flow trade off is worth it. I would be interested to hear any of Kevin's thinking and annecdotal evidence of the benefits of the out-in trade off... Last edited by silent running : 21st December 2007 at 04:54.
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21st December 2007, 05:45	#22 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: Hammerhead CCR Web Pages Up Quote: (Originally Posted by silent running) But I'm still wondering if the lower inlet scrubber temp of a unit with an out-in flow would be more likely to cause a CO2 hit from over breathing during a period of high exertion at the beginning of a dive. I think of all the exploratory dives I've done which have started out in less than calm conditions so I'm sure it's not unusual for somebody to experience a period of high stress/exertion at the beginning of a dive in a new environment. ... How fast is really a function of scrubber dimensions.. If they are sufficient and mosture is available the scrubber should be able to cope pretty rapidly.. The golem scrubber has about 25% more sorb (theorfor contact surface area) than a scrubber the size of the standard prism, and therofoe has the potential to startup even faster.. dimensions are more important that direction.. poor dimensions and the direction doesnt matter.. Look at the difference between the original prism scrubber and the released one, just a small difference in sorb made a BIG difference because the dimensions changed.. Hot gas VS cokd gas towards the sensors doesnt really matter.. what matters is WHERE there is a cooler surface if the gas is still hot, it will contain the same amount of moisture, you wount get condensation until there is a temperature drop.. on the HH the cell faces are VERY close to the exited gas (and a small volume as well) so its unlikely alot of moisture will build on the cell faces.. They are also pointing down (when vertical) so even moisture does end up on the cell it would move off the face in the prone position.. The cooling will be further up the head and then it would run down the tube away from the sensors.. Also remember this since the outlet side of the loop is hotter than the inlet side its capable of holding more moisture.. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated.
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21st December 2007, 06:47	#23 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,780	Re: Hammerhead CCR Web Pages Up Quote: (Originally Posted by jradomski) How fast is really a function of scrubber dimensions.. If they are sufficient and mosture is available the scrubber should be able to cope pretty rapidly.. The golem scrubber has about 25% more sorb (theorfor contact surface area) than a scrubber the size of the standard prism, and therofoe has the potential to startup even faster.. dimensions are more important that direction.. poor dimensions and the direction doesnt matter.. Look at the difference between the original prism scrubber and the released one, just a small difference in sorb made a BIG difference because the dimensions changed.. Hot gas VS cokd gas towards the sensors doesnt really matter.. what matters is WHERE there is a cooler surface if the gas is still hot, it will contain the same amount of moisture, you wount get condensation until there is a temperature drop.. on the HH the cell faces are VERY close to the exited gas (and a small volume as well) so its unlikely alot of moisture will build on the cell faces.. They are also pointing down (when vertical) so even moisture does end up on the cell it would move off the face in the prone position.. The cooling will be further up the head and then it would run down the tube away from the sensors.. Also remember this since the outlet side of the loop is hotter than the inlet side its capable of holding more moisture.. OK Joe, your point about the differences in duration btw the 5.5 and 6lb Prism scrubber are well taken and maybe you're right about the larger proportions/reaction front of the Golem radial making up for the initial inlet temp being lower than an in-out flow. But I could also imagine that a large volume of scrubber material might take longer to reach an optimal temp for the reaction to function efficiently, no matter where the heat comes from. After all, it does take more energy to heat 1 cubic yard of sand to 100F than 1 cubic foot, right? And if flood tolerance is the big concern in the HH design why not also have a drain in the bottom of the scrubber bucket? As for the condensation issue, I can't imagine that having a bunch of condensate forming on surface of the inner tube of an out-in flow scrubber is very good for WOB as it would likely cause the sorb to swell and increase gas flow resistance. Where does the extra moisture go, to the bottom of the scrubber? This could create a similar effect to a flood of an in-out radial, not to mention causing a decrease in the performance of the sorb as the reaction front reaches moisture saturated sorb at the end of the scrubber duration. I'm aware that radial breakthrough is supposed to be more sudden than a simple tube tube axial but, I would guess that the 2 flow directions are not equal in their breakthrough speed. My guess is that an in-out radial has slower breakthrough than out-in due to the increasing size of the reaction front and less clumping due to the condensate clinging to the scrubber bucket wall. I'm happy to chaulk it all up to pros/cons, but I would like to know more about the choices made in the HH design... Last edited by silent running : 21st December 2007 at 06:50.
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21st December 2007, 08:12	#24 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: Hammerhead CCR Web Pages Up Quote: (Originally Posted by silent running) And if flood tolerance is the big concern in the HH design why not also have a drain in the bottom of the scrubber bucket? . No need.. You can trap ALOT of water at the bottom of the bucket.. The normal spacer is at least 2 inches (I never measured it) by over 6 inches in diameter... If my rough approximations are correct thats about 1 l of volume.. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated. Last edited by jradomski : 21st December 2007 at 09:03.
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21st December 2007, 08:55	#25 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,326	Re: Hammerhead CCR Web Pages Up Andy, while I understand and support your thirst knowledge and understanding of scrubber designs there are but few people that can impart it. Else we all would have excellent scrubber designs. More importantly is probably the question "does it really matter?" The pros and cons of the two opposite flow directions have been pointed out pretty well I think. The PRISM has them. The Hammerhead has them. Either way I'm sure you're getting one of the more capable canisters out there, with a lot of absorbing capacity. One has around 6 lbs capacity, the other 7.5 lbs. Which one would be more efficient had they the same capacity might be of intellectual interest, but IMHO doesn't matter as they don't. More important is their duration, rather than how they got there. For the PRISM that's fairly well known as SMI has released some testing data, though more is needed I believe. At CE standards for one thing, to be able to a fair comparison, and for more than 60 ft at that. The Golem scrubber is being tested as Jakub posted, and I hope those tests are done to the general CE protocol, with data for 40 m (plenty of comparable data thanks to Kevin Gurr) and 100 m (available for Inspo, Evo and Ouroboros). The same, really, goes for just about everything else. For an exploration level rebreather flood tolerance or ability to drain the loop are good features to have, even a small, slow leak can add up if you have 5, 8, 10 hrs of deco to worry about. You look at the rig, you look at the features, and you choose what suits you. Anyone with an Optima watching you pack your scrubber with the factory recommended Sodasorb will probably say "No friggin' way". You'll take one look at them changing batteries on their secondaries and say the same. I have no problem with the Hammerhead's scrubber, other than that it's way bigger than what I need. The cell placement issue is different though, I doubt I could get comfortable with that. But that's just me, couple o'hundred Meg divers don't seem to be bothered by it. Same as the lack of an independent pO2 gauge on the AP units. It's a problem for me, several thousand owners don't have it ... shame really, John and Beanie should get rich fixing it. __________________ Cheers Stefan "It is still a good day if you are on the green side of the grass! Su amigo Roberto!" Sponsor Lou in Race For Life! Last edited by caveseeker7 : 21st December 2007 at 08:59.
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26th January 2008, 18:37	#26 (permalink)
Talisman New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2007 Location: Avon Posts: 3	Re: Hammerhead CCR Web Pages Up Is this unit going to be at BTS or Sea Rovers?
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27th January 2008, 01:45	#27 (permalink)
*diverklondike* Moderator Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,463	Re: Hammerhead CCR Web Pages Up Quote: (Originally Posted by Talisman) Is this unit going to be at BTS or Sea Rovers? Yes to BTS... Not sure if Kevin will have a booth or not but he always comes to the show. Regardless I will be there and am happy to bring my rig. I know that Kevin will not be at Sea Rovers. I may but will not bringing a rig. I will however be doing a CCR presentation next Saturday at Northeast Scuba in PA and will have my HH CCR with me. Send a PM if you want more details. Dive Safe Mark
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5th February 2008, 16:01	#28 (permalink)
cameron Classic Kiss 124 Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Apr 2005 Location: Toronto, Ontario, Canada Posts: 245	Re: Hammerhead CCR Web Pages Up Any word on the BMCL for the unit? Any pictures? Cam __________________ Reclaim at work and CCR at home, life is good
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6th March 2008, 11:24	#29 (permalink)
Draggs New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Feb 2008 Location: Yokine Perth Posts: 4	Re: Hammerhead CCR Web Pages Up Hi I have read your info on the hammerhead and it looks to be an awesome piece of technology but there is a few questions like how deap can it go, what does the rig come with like harness etc, as I live in australia how would i go about training for the rig. I am new to all this and just want to buy the best there is for what I want to do with it. I am finishing my open circuit deco tec diving courses and extended range is also on my list of things to do I love the deep oceon and just want to explore what it has to offer. It would be getting used as much as I have time to get into the water want to get into trimix and go deep looking to maybe get to 100metres in a couple of years been diving open circuit for 8 years now and want to move forward and am just really keen to reap the benafits of a rebreather. If you could please help me out with some great ideas and obviously highly experinced advice on towhich rebreather would perhaps be my best option it would be great. Many thanks Draggs
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7th April 2008, 13:30	#30 (permalink)
jont Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Megalodon Prism Topaz Join Date: Oct 2005 Location: New York, NY USA Posts: 191	Re: Hammerhead CCR Web Pages Up Draggs: You can't go wrong with a Hammerhead Rebreather, I have some experience with a number of units and the Hammerhead will in all likelyhood me the next purchase I make, but i'd like to make several sugestions: 1) When it comes to life support equipment NEVER let money (or lack of it) make decisions for you. 2) Look atfeel and try and dive as many units as possible. 3) There are huge differences in quality of construction so understand them. 4) If anyone is giving you the "used car" sales pitch....just stay away as you would. 5) Its important to understand the difference between the various types of Rebreather's out there About the hammerhead there's allot to like: great electronics, very well built (if not the best in that category), huge scrubber, very versatile (depth is really not an issue) CMF ability, the buisness that makes them gives new meaning to the term "customer service" they are the best. The one complaint I have heard (sensor issue) is not as big of a deal as its being made out to be (on THIS unit), but its being handled. Other units to look at are: Meg. Kiss Revo Boris Hope this helps, J
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