How much weight do i need ?

[SalahY]

Hey everyone. So today I started my first open water swimming in pool class and I had to put some weight. The trainer told me put what ever makes you comfortable. I've put two big and two small weights on the belt. ( I don't know know how many kilos/pounds they were) I started to sink fast even when I put air in the BCD.

I weigh 255 lbs/ 116 kilos
How much weight do I need in order to be in a good position instead of sinking in the water.

​Regards,
Salah

 

[boulderjohn]

This should be covered by your instructor. I don't know what agency you are using, but pretty much everyone I know covers it in the course. You should be doing a weight check soon.

The amount of weight you need is best determined by that weight check because we all have different bodies with different needs. If you Google the topic, you will find all sorts of formulas, calculators, and charts. Put in your details (your weight, the kind of wet suit you are using, the kind of tank you are using, etc.), and they will spit out a number in no time. For me, most of them roughly double the amount of weight I actually need.

A big issue is how you carry that weight. If you are a body builder with tons of muscle, that will be very different from someone with a lot of fat.

Another factor is how the instructor is going to teach the class. If he is going to teach you the skills while you are kneeling on the floor of a pool, you will need much more weight than if he is teaching you those same skills while you are neutrally buoyant.

If you were an average 255 pound male in a 3mm wet suit and an aluminum tank in my pool session, I would take a guess based on what you looked like. I might guess 12 pounds for a person your size--maybe less. (I weigh 220, and I typically use 8 pounds in a pool like that, and I am a touch overweighted. Beginning students usually need a little more weight than an experienced diver.) then I would put you in the water and see how you do. I will typically have some weights sitting on the edge of the pool for divers who can't get down because I underestimated their needs.

It will all work out. You don't need to know this now, but you should know what you need by the end of the class.

 

[maj2]

Congratulations on starting your new underwater journey!

We cannot really answer your question, since weighting can be highly subjective, and there is not nearly enough info in your post to even start...

"Two big" and "two small" weights is not terribly helpful. Myself, I have a variety of 2,3,4 and 8 pound weights sitting around the house, and there are more sizes out there. 4 pounds looks big next to a 2, but 4 looks pretty tiny next to an 8!

Were you using a wetsuit in the pool? If so, was is short or long, and do you know how think it was? The more wetsuit material, the "floatier" you will be and the more weight that you will need. If no wetsuit, you would probably require very little weight.

Since muscle is denser than fat, your weight on its own is also hard to use. If that was mostly muscle, you will need less weight. If it is not muscle, then you might need more. Boulderjohn mentioned this as well.

That is just scratching the surface... there are even more variables that can come into play.

Whatever the case, it is clear that you were overweighted, and your instructor's "whatever makes you comfortable" response was unfortunate and less than helpful.

Next class, ask your instructor about what weights you had for class #1. Know the weight. Explain how you sank the first time. They should be able to give you guidance on where to start based on your gear, body shape, etc. It is probably best to start light. You can always add a pound or two.

 

[Neilwood]

Congratulations on starting your new underwater journey!

We cannot really answer your question, since weighting can be highly subjective, and there is not nearly enough info in your post to even start...

"Two big" and "two small" weights is not terribly helpful. Myself, I have a variety of 2,3,4 and 8 pound weights sitting around the house, and there are more sizes out there. 4 pounds looks big next to a 2, but 4 looks pretty tiny next to an 8!

Were you using a wetsuit in the pool? If so, was is short or long, and do you know how think it was? The more wetsuit material, the "floatier" you will be and the more weight that you will need. If no wetsuit, you would probably require very little weight.

Since muscle is denser than fat, your weight on its own is also hard to use. If that was mostly muscle, you will need less weight. If it is not muscle, then you might need more. Boulderjohn mentioned this as well.

That is just scratching the surface... there are even more variables that can come into play.

Whatever the case, it is clear that you were overweighted, and your instructor's "whatever makes you comfortable" response was unfortunate and less than helpful.

Next class, ask your instructor about what weights you had for class #1. Know the weight. Explain how you sank the first time. They should be able to give you guidance on where to start based on your gear, body shape, etc. It is probably best to start light. You can always add a pound or two.

Saloooh91 - congratulations on starting the course. I really enjoyed mine.

I am worried about the instructors approach - how does a new diver with no experience know "what makes them comfortable"? It could have potentially ended up with a situation of the trainee ending up with so much weight that they over compensate with the BCD and shoot out of the water like a rocket or the trainee panics due to dropping too quickly.

Weighting was dealt with pretty near the start of my pool dives - IIRC almost straight after basic drills on the surface ie before I was needing to think about going below the surface.

I started out my pool dives with only BCD, mask, fins, snorkel, cylinder (clothing was swim shorts and a lycra rash vest). Only ended up with about 4lbs in the pool to get to a point where I could sink slowly but balance it with a tiny amount of air in the BCD and my breathing. Was pretty easy to maintain a hover without getting silly with the amount of air in the BCD.

Was completely different in the open water (sea) as I was wearing a 7mm wetsuit which, along with the rest of the gear and the cylinder meant I needed a heck of a lot more weight.

 

[SalahY]

I really appreciates everyones comments here. Thank you all. While doing the class in the sea, the trainer gave us a method where how to know how much weight do you need. He told us to wear our full gear, ( bcd, mask, cylinder, fins, regulator, weight belt and weights ) ( no need for suit in Kuwait since the water down is hot ) he told us to deflate all the air in the bcd and your face should sink it's half bottom down. Meaning my mouth and nose are in the sea and my eyes are out.

Is this correct way to know if the weight is good ?

I also noticed that wearing a weight harness is more comfortable than a belt to me.

 

[spectrum]

While doing the class in the sea, the trainer gave us a method where how to know how much weight do you need. He told us to wear our full gear, ( bcd, mask, cylinder, fins, regulator, weight belt and weights ) ( no need for suit in Kuwait since the water down is hot ) he told us to deflate all the air in the bcd and your face should sink it's half bottom down. Meaning my mouth and nose are in the sea and my eyes are out.

Is this correct way to know if the weight is good ?

I also noticed that wearing a weight harness is more comfortable than a belt to me.

If you do the test your instructor described at the end of the dive (Cylinder pressure ~500 PSI) you will have a pretty good idea. It illustrates that once you are sopping wet you are barely buoyant (~5 lb) at the surface. From there you can anticipate that at safety stop depth you will be about neutral which is the goal. Unfortunately this test is subjective to the amount of compressible protection (neoprene, dry suit garments) you are wearing. If you go in a swimsuit you will be equally buoyant at 15 feet and have a hard time staying down. This test is also at the mercy of wave action, you keeping your fins still and how well your configuration hangs plumb in the water. You can also do this before the dive and add about 5 pounds for the air you will discharge. This has the added downside that many BCs are padded and excessively buoyant at the start of the dive. This can cause the addition of still more unnecessary lead.

Rather than deal with all of that I prefer to simply establish neutral buoyancy with an "empty" cylinder and BC bladder at 10 feet or so at the end of a dive. This is a direct test of your configuration. From 10 feet up you can probably manage the ascent nicely with lung volume, if not add a pound or two so you never go truly positive. Here

A weight harness can be a nice solution and if you prefer it then enjoy it. It lets you play some game with where weight goes for trim and won;t slide off. If you move on to a drysuit it has even more benefits.

Pete

 

[flyin01]

Hey everyone. So today I started my first open water swimming in pool class and I had to put some weight. The trainer told me put what ever makes you comfortable. I've put two big and two small weights on the belt. ( I don't know know how many kilos/pounds they were) I started to sink fast even when I put air in the BCD.

I weigh 255 lbs/ 116 kilos
How much weight do I need in order to be in a good position instead of sinking in the water.

​Regards,
Salah

Then strap on a 250# boat anchor and tell him that feels good.

With all gear on and a tank at 500psi and holding a normal breath you should float at eye level. When you exhale you should sink. The purpose of this is that you can hold a 15ft safety stop.

 

[spectrum]

Hey everyone. So today I started my first open water swimming in pool class and I had to put some weight. The trainer told me put what ever makes you comfortable. I've put two big and two small weights on the belt. ( I don't know know how many kilos/pounds they were) I started to sink fast even when I put air in the BCD.

I weigh 255 lbs/ 116 kilos
How much weight do I need in order to be in a good position instead of sinking in the water.

​Regards,
Salah

I have posted on the "how" but when your post was quoted I realized you may have a few more gaps.

At almost any time in the dive YOU WILL SINK IN THE WATER if you do not have some air in your BCD. At the beginning of the dive you have a full cylinder making you something like 5 pounds "heavy". This equates to about 5 pints of air volume in your BCD.

Assuming a wet suit, it will compress as you dive deeper. The compression will lower your displacement making you less buoyant causing you to sink and requiring some more BC air. Keep in mind that with every bit you descend your neoprene and BCD air will compress requiring the addition of more air to the BCD bladder.

If you are lucky you will have a pressure and depth where you are neutral near the end of the dive. Otherwise you will need to compensate to correct your buoyancy hence you wear a Buoyancy Compensating Device, (BCD).

It is important to identify your weights and keep track of them. Every time you get in the water you have the chance to build a history of what works and what does not. Don't let these data points escape.

As for the instructor telling you to use "whatever makes you comfortable" for weights I pray that he gets around to a better lesson since that answer is totally bogus.

Pete

 

[Reku]

Your instructor should have a good answer for you, however here is a rough estimate that I use.

10% of body + enough to counter act gear.
(add more if using drysuit)
(add 6lbs if in salt water)
(if using sidemount do not count weight for tanks as personal weight.)
(if using doubles you'll need less weight)
(if using al tank you'll need about 4 more lb per tank)
(if using steel tank see tank specifications for weight)

 

[hroark2112]

Your instructor should have a good answer for you, however here is a rough estimate that I use.

10% of body + enough to counter act gear.
(add more if using drysuit)
(add 6lbs if in salt water)
(if using sidemount do not count weight for tanks as personal weight.)
(if using doubles you'll need less weight)
(if using al tank you'll need about 4 more lb per tank)
(if using steel tank see tank specifications for weight)

If I used that formula on my last trip, I would have used 34#. I needed 4 to hold a safety stop with 300 PS1 in my tank.