What is a Counter Ballast System and how to build one?

[martin_gk]

When I was to build my first CBS I was kind of surprised that I could not find any manuel for it anywhere on the net.

Here is my attempt to change that:
What is a Counter Ballast System and how to build one?


I was trying to make it as simple and at the same time as comprehencive as possible.

Please give me your feedback and comments. I would like to develope this document.

Let's spread the knowledge!

 

[whucash]

There are a few threads about conter balance system..try searching in the "No limits" section i think there are a few threads about this.
The system is very easy to build, it looks complicated but once you start building you will end very quickly..
On one side 20kg of metal and on the other side diving rope..between two circles so that the rope could "ride"..ohh and one more..you need a break to free the weight bullet..
http://forums.deeperblue.com/freediving-equipment/81236-buoy-deep-diving.html
Here you can find mine counter balance sstem..a few photos and a bit of how it is build and hhow does it work..
If you have any quesstions ask..i'll be happy to help you.

 

[martin_gk]

Hey whucash,

thanks for the tip but please read my manuel at Under water, where I belong: What is a Counter Ballast System and how to build one? and tell me what you think about it.

About your rubber boat solution: it looks like a good model for training but I would not recodmend it for a competition. When diving at greater depth or somewhere where ther is current I would recodment a longer bar. What did you use as a break?

Cheers
Martin

 

[GirlOfWater]

Check out the video of the conter ballast TEST! This is a thing that should be performed by more people, so that we can get an idea of how well our safety system actually is.

I had the joy of being the freediver "blacking out" at depth and had a speedy trip back to the surface. Everything worked really well, especially with some strong men helping out pulling.

Anybody else tested their CBS?

 

[whucash]

Hey whucash,

thanks for the tip but please read my manuel at Under water, where I belong: What is a Counter Ballast System and how to build one? and tell me what you think about it.

About your rubber boat solution: it looks like a good model for training but I would not recodmend it for a competition. When diving at greater depth or somewhere where ther is current I would recodment a longer bar. What did you use as a break?

Cheers
Martin

Sorry it took so long, I had exams;/
About your counter balance..it looks really great and i think it is much more professional than ours..
I like your idea with the weights, it really makes the c-b system more stable, we used a plastic tank so that the weight wouldn't pull the whole construction.
As for the brake..our weights hangs on a special clip and in case of emergency you just take out the protection and the weights goes down.
I think our construction wouldn't be wide enough for such a big depths..but for training and depths up to -30m it works great.
Cheerse!

 

[Gwaihir]

The cw system looks great, but by the video it looks like the system IS the two guys pulling the rope ?
That cant be the purpose ?
you would be forced to have two on standby for the cw when ever you go out to dive(train)

 

[martin_gk]

Hey Martin,

indeet, the two men pulling are having a big impact. Without that, the speed of 1,3 m per second would not be possible. So it would be wise to include space for two men into the construction of a CBS.

You are right, having these guys around for a training dive is not practical. But thinking that the counter ballast on its own will bring up the diver in time is an illusion. You will have to pull to help it.

Adding extra kilo of weight is also not a solution as it increases the resistance of the water and would not necessary result in more speed. At the same time the risk of an excident with the weight is growing.

After all, Martin, I was thinking of a competition situation. There, the risk is usually higher than in training.

 

[whucash]

Hey Martin,

indeet, the two men pulling are having a big impact. Without that, the speed of 1,3 m per second would not be possible. So it would be wise to include space for two men into the construction of a CBS.

You are right, having these guys around for a training dive is not practical. But thinking that the counter ballast on its own will bring up the diver in time is an illusion. You will have to pull to help it.

Adding extra kilo of weight is also not a solution as it increases the resistance of the water and would not necessary result in more speed. At the same time the risk of an excident with the weight is growing.

After all, Martin, I was thinking of a competition situation. There, the risk is usually higher than in training.

Try changing the shape of the weight..ours looks like a bullet and it really makes a difference than the normal weights..it 'flies' through the water..i think 30kg would be far enough.
One more thing, what do you use at the bottom? Is it a plate or just a rope with weights. We use plate and beneath there are weights.. the palye has a lot of holes so that it swims a ot easier, faster and, what is the most important thing it doesn't swing all over the place.

 

[Gwaihir]

Maby a plate shuld not be used,becouse of the drag it creates ?
a knot with ball shaped "stopper" shuld be enough.
-A plate is beutifulle thoe

 

[Pucko]

I am working on a "new" idea for the counter ballast. Having an solid weight with a hole going through the weight where the rope pass through. This will minimize the risk off getting hit by the weight.
motviktssystem
Some of my ideas...

 

[whucash]

I am working on a "new" idea for the counter ballast. Having an solid weight with a hole going through the weight where the rope pass through. This will minimize the risk off getting hit by the weight.
motviktssystem
Some of my ideas...

We use the same system, with the weight. There is only one differnce, our is an old extinguisher filed with metal and at the end there is special hole for the rope.
It really works, the weight is more stable and it goes down 'slower' but the other side, with the diver goes up more than 1m\s (we tested it only up to 30m).
I think it even prevents from building enormous big counter system because the rope it self doesn't swing and (what tests showed us) it never hits the diver.
I think its far more better than the normal counter weight..
I have to make a couple of pics back down in the garage to show how our counter system looks like, maybe it could help you.
Best wishes from Poland!

 

[apneus]

When I was to build my first CBS I was kind of surprised that I could not find any manuel for it anywhere on the net.

Here is my attempt to change that:
What is a Counter Ballast System and how to build one?


I was trying to make it as simple and at the same time as comprehencive as possible.
Let's spread the knowledge!

I have a question about your counterweight. How did you brake with which and in which direction it stops? I asked about the figure on page
Under water, where I belong: What is a Counter Ballast System and how to build one?

Could you send me a photos of the brake ?

 

[LorenE]

Since there doesn't seem to be a lot of details on how to build these, here's the info on the system I put together. I got the general idea from a system one of my dive buddies had put together using PVC pipe. This is not a competion grade setup. The main goals of my system are to allow for easy adjustment of the bottom plate between dives, and to make it easier to recover a lanyarded diver, compared to the single downline setup we normally use.

The crossbar I use is a pole made of marine grade aluminum.

It is commercially available here for US$40...
shurhold.com/telescoping-handles
It holds the lines 9' (~3M) apart. If you buy two units, three of the sections can be joined together, to hold the lines 12' (~4M) apart. It collapses down to 5' (~1.3M) sections for easier transportation in your car.


I drilled three holes through the pole, for eye bolts, using existing holes where possible. Two for the floats/pulleys, and one for an anchor line attachment point.

For attachment points I used 1/4"x 2” (~6mm x 50mm) stainless steel eye bolts from the hardware store. ( 1/4” x 2-1/2” for the anchor point ).

There are better options ( e.g. marine eye bolts & eye nuts, or ones with larger eyes), but my budget limited me to the hardware store. I used nylock nuts to ensure the nuts do not spin off, and the eye bolts stay securely attached to the pole.



For pulleys/blocks there are many options, just make sure they can handle the weight & line size.
- The first picture below is the basic pulley I use. US$20 each
www.seattlemarine.net/productcart/pc/viewPrd.asp?idproduct=10999
- Second picture is a snatch block which allows for weight/line deployment retrieval without having to thread the pulley each time. This one runs US$45 each
www.seattlemarine.net/productcart/pc/viewPrd.asp?idproduct=3352
- Best of all may be a cam block, as it includes the brake. But the US$150 each price is steep
www.fisheriessupply.com/productgroupdetail.aspx?cid=6063

As far as floats go, there are also many options...
- diving floats www.leisurepro.com/Prod/AQUFC.html

- boat bouy/fenders www.polyformus.com/

- as well as many others...


For a brake you can use one of the following...
- I currently use a basic rope cleat which can be clamped or bolted to the pole. I'll upgrade to one of the other options as resources become available. The cleat option works, but can be tricky to master a quick “secure & release” of the line under load. I use a half figure 8, which works okay for how we've been using the system.

- Here are links to some pre-made rail mounted cleats. I'm not sure how well they would work...?
www.downwindmarine.com/Rail-Mount-Cleat-Pair-4-5-16-Black-Nylon-p-37512.html
or www.downwindmarine.com/Rail-Mount-Cleat-Add-A-Cleat-p-105435.html
- 2 opposite facing clam cleats is another inexpensive option at US$13 each. But an additional mechanism is required to ensure the rope stays in the grooves. Maybe a velcro strap?
www.downwindmarine.com/Clam-Cleats-p-1-c-5883.html

- 2 opposite facing sailing clutches is the deluxe setup at US$70 each
www.sailingsupply.com/index.php?id=33&prod=75

- 2 cam blocks, replacing the need for pulleys is also a nice (and expensive) setup at US$150 each
www.fisheriessupply.com/productgroupdetail.aspx?cid=6063


For a bottom plate I use a yellow frisbee with a hole drilled in the center for the down line. Additional holes were drilled in the frisbee to reduce drag while raising and lowering. If you use this, avoid placing a jam knot just above the plate, as the divers lanyard can catch on it when tuning at the plate. To keep the plate flat, I added a U-braket to the bottom of the frisbee.


I use 25lbs(~11Kg) bottom weights at each end of the downline. For me it's a good balance (no pun intended) between having enough weight for pull downs, and not too much weight for recovering from 130'(~40M) at the end of the day. (note: it's not really enough weight for FIM)


We've tested manual recovery of a diver using the system, and it works well. It may not meet the 1M/s AIDA standard, (Todo: conduct recovery rate test.) but it's certainly better then no counterweight. We have not deployed it with a recovery weight, so it is not currently suitable for competition. Adopting a recovery weight, should be just a matter of beefing up the attachment point hardware, and making sure you have enough floatation at the heavy end of the crossbar.


The rope, floats, weights, and bar length in the images below are just for illustration. No, I don't really use kiddie floats for my counterbalace ;-)

Anyway, I hope this is helpful.