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Old 07-02-15, 09:18 PM   #101
keith_d
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Default Re: Any qualified scuba divers out there?

My preference is for a solid fin, the type which fits over a boot rather than the ones which go directly on your foot.

I would suggest a solid blade because when you're swimming over a silty bottom you usually use a 'frog kick' to avoid disturbing the muck. I don't find split fins work well when you're frog kicking.

Neoprene boots are preferable to slip-on fins because you often find yourself walking over rocks to get to the entry point for a shore dive. Not much fun in bare feet.

Just my opinions,

Keith.
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Old 07-02-15, 09:30 PM   #102
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Default Re: Any qualified scuba divers out there?

And your opinions as a qualified diver to someone just starting out are very welcome! Going to try loads of masks at the dive show next weekend.

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Old 08-02-15, 09:55 AM   #103
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Default Re: Any qualified scuba divers out there?

Just started the theory section now, starting to learn about pressure changes and how they affect air volume and density. As you go deeper and the air volume drops but the density increases, does this mean there is less air available in the tank and your dive time is reduced or that the same amount of air is there but just more dense?

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Old 08-02-15, 07:25 PM   #104
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Default Re: Any qualified scuba divers out there?

The same amount of air is in the tank, but you sup it out at a vastly increased rate.

Your inhalation of (eg) 20 litres a minute at the surface (1 bar) is still the same lung movement at 10 metres underwater, however, at depth this means pulling 20 litres out of your tank.

Every 10m of water increases pressure by 1 bar. So a proper 40m dive, 1 bar of atmosphere plus 4 bar of water... you're supping air 5x faster than at the surface.


Split fins = silt fins. Don't get full foot ones, buy some jet fins or the multitude of copies. Don't worry too much about proper booties, loads secondhand or a knackered pair of converse type trainers.


P.s gonna have some nice stainless backplates and reels for sale soon
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Old 08-02-15, 07:35 PM   #105
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Default Re: Any qualified scuba divers out there?

I think I get it. As the air is more dense, you use it up faster.

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Old 08-02-15, 07:47 PM   #106
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Default Re: Any qualified scuba divers out there?

Pv = nRT, simple innit

Yup.

Fins, I'd just get secondhand.

Mask, try it on, you know the nose-suck-test thing? Buy that very mask not just one of the same model.
Don't forget to clear the release compound crap off it with toothpaste or a lighter.
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Old 08-02-15, 07:53 PM   #107
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Default Re: Any qualified scuba divers out there?

Keith why would you buy a secondhand wetsuit and a new drysuit!!

I tihnk I'd rather have the new (cheap) wetsuit and a secondhand drysuit that doesn't have any secondhand p*ss in it!


My old suit, £90 otter ultimate. Well fooked. 2-3 years use, loads of days out on the boat, god knows how many hours. Needed new neck seal and zip through the time I've had it (£180 or so)

New one, otter brittanic trilam, £80. Zips fine, put some new seals on, bloody marvellous! Baggy but lots warmer than the neoprene with some otter polar D underbits.
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Old 08-02-15, 07:58 PM   #108
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Default Re: Any qualified scuba divers out there?

Quote:
Originally Posted by Kenzie View Post
I think I get it. As the air is more dense, you use it up faster.

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So if you consume 18 litres a minute at the surface, how many bar will you use up out of a 15l tank if you spend 15 minutes at 25m depth?
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Old 08-02-15, 08:36 PM   #109
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Default Re: Re: Any qualified scuba divers out there?

Quote:
Originally Posted by yorkie_chris View Post
So if you consume 18 litres a minute at the surface, how many bar will you use up out of a 15l tank if you spend 15 minutes at 25m depth?
At the moment I don't know the maths well enough to work that out.

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Old 08-02-15, 09:13 PM   #110
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Default Re: Any qualified scuba divers out there?

Quote:
Originally Posted by yorkie_chris View Post
Keith why would you buy a secondhand wetsuit and a new drysuit!!

I tihnk I'd rather have the new (cheap) wetsuit and a secondhand drysuit that doesn't have any secondhand p*ss in it!
I bought a new drysuit because I'm not a standard size. I've got a long body and short arms and legs so finding an off the peg suit that's even close is difficult.

If you're fortunate enough to be an off the peg size and can find a secondhand suit for a good price that's great. I ended up going to LIDs and trying on dozens 'til I found one that was affordable, and almost the right size. That lasted me until I'd decided I liked UK diving enough to buy my current suit.

These days I dive a fudged to measure membrane suit (XL with 2" off arms and legs & adjusted pockets) which fits me pretty well.
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