Fins! Negative bouyancy.

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Used to dive with an AP Valves BC and a 15l steel cylinder. I needed to do similar to @Endler’s and stack my weights either side of the weight belt buckle to act like a keel. The 15l steel cylinder had a tendency to try to flip me on my back. It depends on how negative the cylinder is.
 
That's really helpful thanks.

So I use an AP Valves Buddy Profile BCD and I've got a 15l steel tank.

Weight wise, yes, about that. I think it's about 28lb on a boat dive, and I need the extra when I'm shore diving as the minute I am deep enough to actually swim, I start rolling around. With 28lb on a boat dive I'm able to control at the bottom really well. As soon as I get to about 6m on a shore dive, it's the same, but the swim out can be a bit of a pain, especially in any currents.

I'll check out the post, thank you. I'm not sure if I can swap the back plate in my BCD but I can have a look into it.

Thanks again,

B

Biting the bullet and replacing the BCD may well be worth the improvement in your diving comfort long term. Find a BSAC club and see if someone knows how to set them up and let you try one.
 
That's what I thought. I'm new and have just bought a BCD so don't really want to go and buy a new set up.
Yeah, this is a strange sport. When starting out one can buy a jacket BCD with all good reasons and intentions only to find out a backplate and wing setup is much better. Ask me how I know.
 
Genuine Scubapro Jet Fins!

And normally I would not consider ankle weights as a recommendation but there are folks who might get on with them okay. Whatever BC you have if it is similar to so many popular types you should be able to make do, no need for a wing and a plate unless you have money to burn. Buying a bunch of different equipment as a new diver is a good way to reduce your bank account and have nothing you are satisfied with in the end.

James
 
I am not a fan of SP Jet Fins [the horror] :eek:
have look at the Hollis F1.
I find the foot pocket, and spring straps a better fit for me.
Hollis_F1_Fin_1024x1024.jpg
 
F1 hollis fins are very responsive and great for power and manoeuvring with little ankle movements and are heavy so good for floaty feet and good for frog kicks
RK 3 are lighter and good for heavy feet - and excellent fro flutter kicks - dont have the same responsiveness as the F1 and tend to create a bit more turbulence in frog kicks but a good fin all the same

not sure about others - i do have a pair of frog cressy and a pair of aqualung but id say they're more recreational
 
That's really helpful thanks.

So I use an AP Valves Buddy Profile BCD and I've got a 15l steel tank.

Weight wise, yes, about that. I think it's about 28lb on a boat dive, and I need the extra when I'm shore diving as the minute I am deep enough to actually swim, I start rolling around. With 28lb on a boat dive I'm able to control at the bottom really well. As soon as I get to about 6m on a shore dive, it's the same, but the swim out can be a bit of a pain, especially in any currents.

I'll check out the post, thank you. I'm not sure if I can swap the back plate in my BCD but I can have a look into it.

Thanks again,

B


I'm not quite clear on what exact BCD you are using, but it looks like you've got more weight than the BCD can compensate for. If that's the case you're into "not safe" territory.

From AP's manual

1665490713500.png


A 15L steel is going to be another 4 or 5 kilos negative at the start of the dive (I think - someone will surely correct me if I'm off).

My guess is your biggest issue is how you were trained. Instead of looking for more equipment, take @tbone1004 's advice, or find a new instructor/shop. If you can find someone who trains students in neutral buoyancy during open water, that person will probably be able to help.
 
I'm not quite clear on what exact BCD you are using, but it looks like you've got more weight than the BCD can compensate for. If that's the case you're into "not safe" territory.

From AP's manual

View attachment 748005

A 15L steel is going to be another 4 or 5 kilos negative at the start of the dive (I think - someone will surely correct me if I'm off).

My guess is your biggest issue is how you were trained. Instead of looking for more equipment, take @tbone1004 's advice, or find a new instructor/shop. If you can find someone who trains students in neutral buoyancy during open water, that person will probably be able to help.
I understood that the BC needs to compensate for gas in the cylinder and loss of bouyancy of this suit. Air in a 232BAR 15l cylinder is approx 4.2kg. Using @tbone1004 guesstimate of no more than 10kg. 10 + 4.2 = 14.2kg With complete compression of the wetsuit. Assuming @Ellabee83 has a large size of 16.66kg, this should be OK. The BC should be capable of floating it’s self and cylinder, as this model has no integrated weights.
 
Hi all ,

To avoid lots of "bitty" replies.. I'll do a bulk one, but won't tag anyone.

In brief, I have an AP ranger td BCD in large. I'm in a 7mm suit and 6mm boots and am about 18stone so I've got plenty of natural buoyancy (which I'm trying to reduce)!

To be honest, our instructor has been great - he's a commercial diver and advised against a wing. I'm really happy with my BCD and don't really feel a huge need to change it up. It's more about making small changes where it will help and be beneficial. I'm an hourglass figure so weight belts are very much around my waist and not on my hips, placing them further up. I wear my tank as low as safely possible before the concave of the top would cause it to slip out. But even with some significant natural buoyancy on my chest, my bum and hips more than balance it out, causing my lower half to be far more naturally buoyant than the top half. Any dives below about 6m I'm absolutely fine because once I'm down I'm sorted. It's the lower dives,especially if we're in from the start (I.e. not surface swimming put to depth) that are more of an issue.

I am joining a local club from April, but I'm not around enough over this winter to warrant paying the annual fee for a couple of dives before the new year.

I tried the scubapro jet fins in a shop last week- I need an xl and they are huge! Unfortunately I'm about 5hrs from Mike's so it's not a trek I'm likely to make in the near future, but would tie it in if I was close by.

We were trained in neutral buoyancy, it's more that the conditions of every dive I've done so far have been massively different, and have led to me in various positions of ungainliness and a struggle to maintain any kind of trim. Think currents, choppy seas, swell etc. I know as time goes on and I'm more used to things I will learn to compensate more, but would like an initial helping hand in the right direction to make some of it a little easier.
 

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