Pony bottles for free diving

[Cantclimbtom]

Just from idle curiosity... And as a disclaimer I'm neither suggesting or advocating using a small single cylinder to push long free dives that are not really free dives!
Rather as assistance for something that is free-able but pushing the limits or comfort. Yes a grey area... Yes opinions will differ

So - pony bottles... in practical terms how are they used, do people stuff them inside the zip of a caving suit, would a 3 litre bailout actually fit while crawling about in a sump? Jerry rig a sort of sidemount, to a caving belt. How does it actually work in practical terms?

 

[Benfool]

Usually a belt and either a sling or some bungee works well - see Duncan's website here:

http://www.sump4.com/sidemount/simplesidemount2.jpg

You can also rig up something half decent with a srt harness and a mtde garma chest harness, with some added bungees.

 

[Cantclimbtom]

Wow thanks Ben, a wealth of other useful stuff on that site too!

 

[Steve Clark]

I’ve used a 1L bottle (usually used for suit inflation) with two jubilee clips to hold a piece of webbing on to create a belt loop. I then just thread this on to a normal caving belt. Most of the trip I just carry it in a bag with some padding around it.

This works fine for things like Rowten sumps without any stress.

I wouldn’t use it for anything longer / rigged with dive line.

 

[PeteHall]

I'm neither suggesting or advocating using a small single cylinder to push long free dives that are not really free dives!
Yes a grey area... Yes opinions will differ

The Cave Diving Group Manual does detail situations where a single breathing set may be appropriate (caveats apply).

The technique is therefore considered uncontroversial, however the question of when it is appropriate may be open to more debate.

In general terms, use two sets wherever possible if you want to rely on being able to breathe.

Beyond that, the bungee loop and caving belt setup as described by @Duncan Price is very effective for 1, 2 or 3 litre cylinders. Anything larger and you should probably be using 2 bottles and a proper harness.

If you want to carry the cylinder on your "harness", it's best to remove the regulator and carry that in a suitable tub, then make sure that the cylinder valve can't slip out of the bungee loop (either adding extra turn with the bungee, or add a krab to the neck of the cylinder to clip it off). When the regulator is fitted, it can't slip out of the bungee, so this is only a concern for carrying.

Also, consider putting a steel insert/ blanking plug into the cylinder valve to minimise the chance of it getting damaged in transit.

 

[Duncan Price]

I’ve used a 1L bottle (usually used for suit inflation) with two jubilee clips to hold a piece of webbing on to create a belt loop. I then just thread this on to a normal caving belt. Most of the trip I just carry it in a bag with some padding around it.

This works fine for things like Rowten sumps without any stress.

I wouldn’t use it for anything longer / rigged with dive line.

Like this

http://www.sump4.com/sidemount/beltattachment1.jpg

and this (very old photo)

http://www.sump4.com/sidemount/britishsidemount1.jpg

 

[Steve Clark]

Yep. Just like that.

 

[Cantclimbtom]

Slightly maybe irrationally nervous about using a 1 litre, the thought of somehow entering a sump with a bottle of argon (or hopefully getting to the "All" of Bruce Willis and then abandoning it) but I suppose it's always essential to label things and know with absolute certainty what's in what, but for some reason that just makes me feel nervous, a bit like I don't drink from red Sigg bottles

Those pics really helps, thanks SC and DP

 

[wormster]

Oh no!! You don't need a gag and bottle for Swildons Sump 1!!!

 

[mrodoc]

I think it is important to emphasise one should be familiar with the kit before doing this. About 40 years ago during exploration in Morocco we dived a sump that proved to be an easy free dive (shallow, smooth floor no obstructions and only about 4m long). One member of the team, a non diver, was reluctant to free dive it so I suggested he used my bottle and reg (I was planning to push into a deep sump further into the cave) to go through in case he needed to take a breath. In he went. There was quite an interval then he emerged coughing gasping and spluttering saying he had nearly 'croaked it' in there. It hadn't changed and was still a very easy free dive but his anxiety had obviously caused him to rush in and generally get in a pickle. Lesson learnt!

 

[mrodoc]

Slightly maybe irrationally nervous about using a 1 litre, the thought of somehow entering a sump with a bottle of argon (or hopefully getting to the "All" of Bruce Willis and then abandoning it) but I suppose it's always essential to label things and know with absolute certainty what's in what, but for some reason that just makes me feel nervous, a bit like I don't drink from red Sigg bottles

Those pics really helps, thanks SC and DP

Like the bit about red Sigg bottles. I had one confiscated from my baggage once by US customs despite it being empty and previously well rinsed on the grounds it contained flammable material. Some of them are not the brightest sparks!

 

[PeteHall]

I think it is important to emphasise one should be familiar with the kit before doing this.

The same could be said of SRT...
As within life support-equipment, if you don't know how to use it, it could just as easily be life-ending.

 

[Cantclimbtom]

The same could be said of SRT...
As within life support-equipment, if you don't know how to use it, it could just as easily be life-ending.

Agreed. It's just an irrational discomfort and my personal weirdness I need to get over, like not liking red drinking bottles even if someone else's and they've never used it for fuel. Or checking double-back buckles are doubled back before every srt drop even if drops are next to each other (I've lots more examples of ritualised checks but you probably already suspect I'm weird so I better not confirm that further)

 

[Cantclimbtom]

Oh no!! You don't need a gag and bottle for Swildons Sump 1!!!

Not sure, I've seen The Hunters Arms described as a short walk from Priddy Village, so not having enjoyed sump 1 yet, that 6 foot in the description could be a good 30ft+

 

[Steve Clark]

A simple mask and hood makes a free dive sump far easier than without. It also means you can lie on your back without water going up your nose, which makes the sump feel shorter because your face is only underwater for the absolute minimum air-space to air-space distance.

Relax, lie still and pull gently. Slow is smooth and smooth is fast.

 

[Tricky Dicky]

When diving Swildons sump one, get a friend to tap a rock on your helmet as you exit the sump, making you think that you are still in the sump, all the way along the line - my how I laughed...........................

 

[PeteHall]

Not sure, I've seen The Hunters Arms described as a short walk from Priddy Village, so not having enjoyed sump 1 yet, that 6 foot in the description could be a good 30ft+

These days, the first sump you normally get to in Swildon's is about 8m long, though for historical reasons, it's called Sump 2.

For several years now, Sump 1 seems to be a duck more often than a sump. At this time of year, I'd be extremely surprised if there wasn't an air space. Even when it is closed, it's usually no more than a foot or two unless the cave is wet enough for it to back up. At a guess, I'd say the longest I've known it (in pretty sporting conditions), was 6-8 foot tops based on where the water level was, but I didn't actually measure it, so don't quote me on it.

 

[Cantclimbtom]

Thanks Pete, I think mention of pony bottles for Swildon's sump 1 and it's 30+ foot length (as above) was in humour. Next time I'm in the area (e.g. a Vobster Quay trip in the quite near, but undefined, future) I might explore a bit more of Swildon's... perhaps into Swildon 2, but without pony

My idle curiosity, prompting daft questions had been piqued by other sumps which are free-able but difficult free. I hadn't thought of Rowten at the time of the original post .. but that is a fine idea though!

Picked up a lot of good info here. Thanks again everyone.

 

[wormster]

Sump 2 requires just some lead, big lungs and huge stainless steel cahunas!! Sump 1 is a doozy by comparison!!

 

[domestos bend]

How long would a 3 litre bottle last roughly assuming shallow dive breathing normally.