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Discussion Starter · #1 ·
I currently dive with a 15L steel and 10kg of additional weight. I am adding a 3L pony to my set up and want to know what to expect as far as boyancy goes. I have weighed the 3L pony and it comes in at 6kg.

I'm thinking I'll just remove 6kg from my weight system?

Probably a silly question!

Thanks
 

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No, you need to take off the amount of weight minus the weight of the water it displaces. Basically the negative buoyancy.

Best thing to do is try taking off a kilo(ish) and doing a weight check. But I find it's normally a kilo, if that.

Digs.
 

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Wannabe Lotto Jackpot Winner..!
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I think you'll find 6kgs is far too much th take off, try 1 - 2kgs max and see how you get on.
 

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This also assumes that the pony is permanently (at least for the dive) attached, and you will not be removing it for any reason. If you have plans to take it off at all underwater then you need to ignore it in your weighting. But most of us don't plan on taking a pony off at all.

Digs.
 

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Discussion Starter · #5 ·
Yeah I remebered something about the water displacement becasue I am taking down an air filled cylinder and not a 6kg weight!

Glad I asked, thnaks guys!:teeth:
 

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Yeah I remebered something about the water displacement becasue I am taking down an air filled cylinder and not a 6kg weight!

Glad I asked, thnaks guys!:teeth:
It's why we're here. To talk about diving. And we love talking about diving. Oh yes we do. I'm so tired I've got a bit silly now. My apologies.

Oh, and depending on what the pony is made out of you might well find that you don't need to change your weight at all. Though steel ponies are the norm in the UK, you can get allys and I've seen a few. Very lovely they are. Like dogs dressed as humans. An unexpected bonus.

Digs.
 

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YDs Most Southerly Monkey
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It's why we're here. To talk about diving. And we love talking about diving. Oh yes we do. I'm so tired I've got a bit silly now. My apologies.

Oh, and depending on what the pony is made out of you might well find that you don't need to change your weight at all. Though steel ponies are the norm in the UK, you can get allys and I've seen a few. Very lovely they are. Like dogs dressed as humans. An unexpected bonus.

Digs.
That's why I have an Ally pony.
 

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I find that I can take off two kilos with my pony attached. Initially I only used it if I was going deeper than 15m, but because on dry land it's only an extra 4kg ish to carry I now use it on all dives, even shore dives down to a max depth of 6m - you can never have too much air!:teeth:

Irfon
 

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Jonah
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If you're taking weight off when adding a pony, remember that you need to be able to be neutral with EMPTY main cylinder and ALMOST empty pony (because that's what the situation could well be when you're approaching the surface breathing off the pony). The last thing you want is for an already serious situation to be compounded by an uncontrolled ascent.

I don't take off any weight at all when I use a pony.
 

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Nigel Hewitt
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If you're taking weight off when adding a pony, remember that you need to be able to be neutral with EMPTY main cylinder and ALMOST empty pony (because that's what the situation could well be when you're approaching the surface breathing off the pony). The last thing you want is for an already serious situation to be compounded by an uncontrolled ascent.
Tom's on the money here.

Saving your buddy from certain death but then making an unplanned buoyant ascent because you can't hold the stop you both need when you breathe down your reserves lacks finesse. You need to be able to hold the stop right down to empty as lead is cheap but those last breaths of air can be very valuable.
 

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Underwater Ogre
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I have just undergone the same transition, adding a 3l steel faber pony to a 15l stee lfaber. I dropped 2kg and experienced no problems.
 

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I have just undergone the same transition, adding a 3l steel faber pony to a 15l stee lfaber. I dropped 2kg and experienced no problems.
Have just done similar, and found dropping 1kg worked for me, also only dropped it from the right side, so my trim is still fine with the pony attached to the right side of the tank. Also thanks to a suggestion from Tim at Vobster and trying some OOA drills with my buddy, I've necklaced the pony reg and moved my occy to my left side.
Doug
 
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