[w ripley]

I haven't taken my Meg into a cave yet, but am concerned about hitting the canister on the ceiling.

I've got about 200 hours OC in caves and have been impressed with how the doubles look after a two to four hour cave dive -- lots of cave lipstick from kissing the rocks. Sorry, but it happens and even more so when going thru restrictions like Rocky Horror at Madison or getting into Cow for examples. And, every once in a while the tanks take a pretty good jolt when hitting a rock while scootering.

So, with the Meg tanks resting close to the wings, that leaves the cannister lid sitting out there to take the initial impact. Worst, the lid is perpendicular to the canister body, while the tops of the doubles are more angled (rounded) which helps to deflect their hit.

Will the canister take it or is there some protection that can be added?

Thanks

Bill

[wedivebc]

Quote: (Originally Posted by w ripley)

I haven't taken my Meg into a cave yet, but am concerned about hitting the canister on the ceiling.

I've got about 200 hours OC in caves and have been impressed with how the doubles look after a two to four hour cave dive -- lots of cave lipstick from kissing the rocks. Sorry, but it happens and even more so when going thru restrictions like Rocky Horror at Madison or getting into Cow for examples. And, every once in a while the tanks take a pretty good jolt when hitting a rock while scootering.

So, with the Meg tanks resting close to the wings, that leaves the cannister lid sitting out there to take the initial impact. Worst, the lid is perpendicular to the canister body, while the tops of the doubles are more angled (rounded) which helps to deflect their hit.

Will the canister take it or is there some protection that can be added?

Thanks

Bill

Most of the scarring on my meg from wrecks and caves is on the lid handle. The ISC logo is almost worn off the can, but everything else is solid.
Last year when entering a cenote my buddy, also on a meg tripped and fell over backward. He slid down on some wet rocks and I was already in the water watching helplessly. I shouted "Oh my god are you alright?" He replied "Don't worry the rebreather broke my fall". We both started laughing as we realized what he had just said. If it had been another rebreather where would have been bits of broken plastic all over the cenote. He conducted a pos/neg test, checked the PO2 readings and did a 2 hr cave dive.

[diver1369]

Dave:

Was that a 'Pepsi Blue' cannister he fell on?

Regards,

jb

Quote: (Originally Posted by wedivebc)

Last year when entering a cenote my buddy, also on a meg tripped and fell over backward. He slid down on some wet rocks and I was already in the water watching helplessly. I shouted "Oh my god are you alright?" He replied "Don't worry the rebreather broke my fall".

[wedivebc]

Quote: (Originally Posted by diver1369)

Dave:

Was that a 'Pepsi Blue' cannister he fell on?

Regards,

jb

Yeah it was the first couple dives after it was anodized too. It put a good size scratch on it but he has turned the can 90' so you can't see it any more

[Benthic]

I wouldn't worry about it too much, the Meg is a very tough unit.

Heather and I cave dive with our units quite a bit. We use them both on foot and with scooters. As Dave mentioned, the handle on the head takes some hits, as do the top of the cylinders but it's all cosmetic only. When I made the switch from OC to CCR I had to 'get used' to the size of the Meg on my back. So there were ceiling hits a lot in the beginning, but as I have it longer, they get less and less frequent.

Brian

[mattmexico]

yo

The impact it seems, is divided between tanks and lid. Attached to this post is a photo of my Meg, dived by a student of mine. As he is diving in a very horizontal position ( very good ) I realize that there are others who might come a bit more vertical ( not so good ). As they come vertical besides not streamlining, more drag, sediment agitation or others they bring their unit closer to the ceiling. As long as they dive 3 ltr tanks or 19cft tanks the tanks will most likely be longer, and inpact the cave before the lid. However, there are impacts that are done horizontal and that can and will result in impact withthe handle.

Two people told me on independent occacions that the handle was created to absorb the impact ... and I have seen some pre handle units that went cave diving ... and I could believe that.

The very reason I keep my tanks valves mounted down is valve protection. When impactig the cave I will not damage first stage and possibly have a auto shut-off by a roll-shut. The tank bottom end of the tank will take the impact much better then the valve end of the tank.

The lid does some shock absorbing too as I can see on the scratches on my handle.

All in all the unit is as sturdy as a blockbuster ....

saludos
Matt

[wedivebc]

Quote: (Originally Posted by mattmexico)

The very reason I keep my tanks valves mounted down is valve protection. When impactig the cave I will not damage first stage and possibly have a auto shut-off by a roll-shut.

You, impact caves? Say it ain't so.

[mattmexico]

yo

... when diving through restrictions there is almost no other way then to slowly scrape through ....

... when going after renegade students, in very unlikely events, they and I might touch the ceiling or bottom .....

... years ago when I was in the process of becoming a intro to cave instructor it hit me like a freight train. That I, the person I am, loving and sworn to protect these caves, have to plan and conduct dives that will include drills where we have at times no choice, at least taking in as a large possibility the chance to have negative impact onto the cave environment. I am talking about zero viz drills, touch contact, primary light failure, lost line and the like ... and as we are here on Rebreather World ... all the rebreather emergency related drills inside a cave such as hypercapnia, hyperoxia, hypoxia, flooded loop recovery and all that good stuff.

When we have to balance the developement of safe cave diver training and the protection of the environment it is a heavy load I feel on top of my broad shoulders, having to make that descicion. Yes, we do conduct drills in areas where nothing can be destroyed, and all cave instructors are supposed to conduct the drill in the same areas but still ... most training agencies have a list of zero viz drill areas published that identify locations in Florida and Mexico.

I have attached the original article I have written in 1997 or 1998 when I was living here 2 1/2 years, now I am in my 12th year. It was back then publsihed in the NSS-CDS publication - Underwater Speleology Magazine - ... and I still feel the same .... stronger then ever.

saludos
Matt

[Paul Evans]

Matt

The placement of the weights in the photo must help a bit

[caveseeker7]

Matt, any chance you could turn that MS file into a PDF for those of us that are trying to get by without Billyboy's software?