Author Topic: Famous bit of dive kit  (Read 2169 times)

Offline Pitlamp

  • forum hero
  • *****
  • Posts: 5996
Re: Famous bit of dive kit
« Reply #25 on: July 21, 2021, 12:50:51 pm »
The compass is one of the most important pieces of equipment for a cave diver.

...its principle use is to tell you where your (steel) cylinders are.

 8)

Even so, a standard magnetic compass was used to create a survey of a well known northern underwater cave with a misclosure of just 0.7%. I'll settle for that accuracy, if trying to relocate a main line.

Offline Duncan Price

  • forum star
  • ****
  • Posts: 663
Re: Famous bit of dive kit
« Reply #26 on: July 21, 2021, 02:12:10 pm »
The compass is one of the most important pieces of equipment for a cave diver.

...its principle use is to tell you where your (steel) cylinders are.

 8)

Even so, a standard magnetic compass was used to create a survey of a well known northern underwater cave with a misclosure of just 0.7%. I'll settle for that accuracy, if trying to relocate a main line.

I have only found it a problem with smaller cylinders - my 3's are very magnetic.  For accurate survey work I used to remove the compass from my wrist and hold it out in front of me to sight along the line.  I drifted away from the line once whilst making notes in Pwll-y-Cwm.  Rather than deploy my search reel, I simply looked at my notes, set my compass to 90° from my direction of travel and was able to find the line straight away.  My main use for a search reel has been to perform (temporary) repairs to broken lines.

Offline Paul Marvin

  • obsessive maniac
  • ***
  • Posts: 351
  • Bronze, Silver & Gold Swimming Certificates, WGAS
Re: Famous bit of dive kit
« Reply #27 on: July 21, 2021, 05:50:09 pm »
Yep, pretty much what Sam said.

You've lost the line in zero visibility. You attach the line reel to a handy rock (some emergency line reels have a lead weight on it so you dont need to do this) and use this to find the line. This can be done using several methods - one of which is to head out in spokes like Sam mentioned. Another is to feed out a length of line and go around in a circle looking for the line until you think you've gone all the way around. Then feed out another length and go around again. Repeat until you've either found the line or run out of gas.

Its really hard and is a last resort. Most import thing is to not loose the line in the first place.

Would dive lines usually be to the side of passages or chambers? (I'm thinking mines here rather than narrow cave systems)? Or could they run though large flooded chambers?
If the line runs through the middle of a chamber, when you re-find the line, how do you know in which direction to follow it? I've seen tags/arrows tied on the line....?





Phil generally speaking I like to put line on the left going in and as low as poss but usually things have to change when looking for a belay point , its not generally a good idea to keep criss crossing passages or lines to high as they become bad tangle points. The only time I got tangled in one was a high one that caught around my helmet lights , apart from when I was training when  Gavin Newman used to like to tangle you up on purpose as part of a drill  whilst wearing no mask. Nowadays the no mask scenario has been replaced with a blacked out mask
I dont know where I am going, but will know where I am when I get there.

Online Cantclimbtom

  • menacing presence
  • **
  • Posts: 217
Re: Famous bit of dive kit
« Reply #28 on: July 22, 2021, 05:45:28 pm »
Just watched "Underground Eiger"  (and a couple of other relevant Sid Perou films), being a non diver that put the reel into context. Some great films there!
Expert in incompetent tomfoolery

Offline Paul Marvin

  • obsessive maniac
  • ***
  • Posts: 351
  • Bronze, Silver & Gold Swimming Certificates, WGAS
Re: Famous bit of dive kit
« Reply #29 on: July 22, 2021, 06:04:32 pm »
Just watched "Underground Eiger"  (and a couple of other relevant Sid Perou films), being a non diver that put the reel into context. Some great films there!

Yes they are very important
I dont know where I am going, but will know where I am when I get there.

Offline Blueberry

  • Newbie
  • *
  • Posts: 29
Re: Famous bit of dive kit
« Reply #30 on: July 23, 2021, 10:41:28 am »
A good film is 'The Ario Dream- The quest for Europe's Deepest Cave' can be found on Amazon Prime. Featuring Tony Seddon of Starless River. Interesting to see how Russians cave too.

Online Benfool

  • forum star
  • ****
  • Posts: 559
Re: Famous bit of dive kit
« Reply #31 on: July 23, 2021, 10:59:07 am »
The Underground Eiger wasn't actually made by Sid, although I believe Lindsay Dodd was involved who did the sound for many of Sid's films.

I personally think its the best caving film ever made and has been really inspirational to my own cave diving.

B

Online aricooperdavis

  • forum star
  • ****
  • Posts: 570
  • Cornwall to Cumbria
    • Cooper-Davis.net
Re: Famous bit of dive kit
« Reply #32 on: July 23, 2021, 11:01:58 am »
A good film is 'The Ario Dream- The quest for Europe's Deepest Cave' can be found on Amazon Prime. Featuring Tony Seddon of Starless River. Interesting to see how Russians cave too.

Also available on Vimeo On Demand if you don't like supporting that tax avoiding astro-bellend :halo:

Offline Ian Ball

  • forum hero
  • *****
  • Posts: 1132
Re: Famous bit of dive kit
« Reply #33 on: July 23, 2021, 12:06:07 pm »
Tony?

Offline Blueberry

  • Newbie
  • *
  • Posts: 29
Re: Famous bit of dive kit
« Reply #34 on: July 23, 2021, 05:40:37 pm »
Tony?

Spoiler alert, he makes the connection.

Online sinker

  • menacing presence
  • **
  • Posts: 194
  • O-Level woodwork BlockbusterVideo Gold Card
Re: Famous bit of dive kit
« Reply #35 on: July 24, 2021, 09:41:13 am »

.....tax avoiding astro-bellend


 :lol:  :lol:  :lol:  :lol:  :clap2:
Ah, well, now, you see...erm...

 

Main Menu

Forum Home Help Search
SimplePortal 2.3.5 © 2008-2012, SimplePortal