Weighting + rental gear, bouancy + 7.2L lungs

[tank29]

I am in the process of geting my OW cert and proper weighting and bouancy control are things that I know are tricky for new folks to get right. I was hoping some people here might be able to help me get a little better.

I have read a number of posts in this forum about techniques for proper weighting and they make sense. The question I have is, what do you do when you add rental gear into the mix? Will that significantly vary the amount of weight you need? Or can you get a baseline and sort of eyeball it from there? Because the gear may change from dive to dive if I'm renting (which I'll be doing as I'm starting out).

The other question I have is about bouancy. If I recall correctly, the PADI OW manual says to breathe slowly and deeply, vice short and shallow. This can be an interesting proposition for me, as I have pretty large lungs (7.2L capacity). For example, on a fin pivot test, I will go from lying flat on the bottom of the pool, to completely upright in one breathe. At the end of the pool session I was controlling my bouancy by taking much shorter breaths when I started to float a bit. But then I seemed to be violating the breathing principle. Any thoughts or suggestions?

Please let me know what ye wise ones think! Thanks for the help!

 

[spectrum]

Lets's start with the breathing....
You will tend to rise and fall in the water column as you breathe in a slow deliberate manner. Good timing can counteract a lot of it. With practice you can develop a cycle where you are inhaling just as you begin to fall and exhale just as you begin to rise. This can counteract a lot of what you experieince in the fin pivot. As you point out this is exacerbated for someone with a large lung capacity. Like the rest of your buoyancy control it will come together with diligent practice.

As for rental gear it should not be a huge thing to mamage. Staying with aluminum 80s is almost a sure thing. They are not all identical but they are close. Rental BS are not apt to be plush so they will not generally have a lot in inherent buoyacy. The regulator set will also be close from shop to shop. A rental wetsuit is probably the biggest wild-card.

Pete

 

[plot]

Rental gear shouldn't effect you too much. I figure the worst case scenario, you have to add more weight, or possibly remove some before your second dive.

Short shallow breaths can lead to hyperventilation and panic which is why they don't recommend it. You don't have to take in deep slow breaths. I try breathing normally, and adjust my breathing as needed... as I find getting neutrally bouyant has alot to do with my breathing.

For example, I might take a deep breath, then exhale only halfway before inhaling again. You don't have to empty your lungs with every breath. You don't have to fill them with every breath either. If I feel myself start to float up, first thing I do is start exhaling... and exhaling... and exhaling... you'll find you're amazed at how long you can exhale sometimes, and pretty soon you'll back down down to where you wanna be. Granted, these types of breathing techniques are only for minor adjustments and even with 7.2L lungs it still won't replace your BC, but it's very important to be aware of it. The most important thing to remember, is to exhale while you're ascending so you don't blow up your lungs as the air inside them expands.

 

[GA Under Water]

I found that I got my bouyancy just right with breathing normally. to fall I force out all the air I can then return to normal when I get to a level I want Take an overly deep breath to rise kind of like a yawn or the Deep breath you take from time to time just to get a little extra air in your lungs.

With the gear you can eyeball it to about 2 - 4 pounds once you get used to it.

When I moved from a 3mm 12 lbs.to a 7mm with hood, gloves, boots I added 12 pounds for 24 lbs. But then next I went to a 3/5mm Semi-Dry and a Ultra-lite BC and had to remove 4 lbs to make 20. This was using different BCs, Exposure suits, Fins, and other things I was renting at the time.

The most weight I had to use was with a rented SeaQuest 7mm Farmer John, 6mm Mares Hood, and Mares Dragon BC. the Mares Dragon was the hardest BC I have tried to get Trimmed. I have tried Mares, Oceanic, and a couple others that I can't remember the names of.

What is your Weight, Body type, BC, Exposure, and other gear? You can get a pretty good guesstimate from that Info. Trimming out takes a few more tries and trial and error. with things like +, - or neutral Fins, which pockets to add one punders to to level you out.