Question onproper weighting...

[Spectre]

MikeFerrara once bubbled...
If your neutral at 15 ft you'll be buoyant above that. Don't you want to be able to control your ascent all the way to the surface?

Exactly. The shallow you are, the more important a slow ascent is. I've seen far far far too many people do their 15 foot stop, then let go and rocket to the surface.

I re-evaluate my weighting quite a bit on basic shore dives. In fact I did that today in prep for my 'winter' diving with my full ensemble of undergarments. Sure enough, second dive, 1600 psi in my tank, 9 feet under the water. I looked at my buddy and gave the 'thumbs up'. Not to say 'lets surface' but to say 'yep.. I'm surfacing!". A quick little bit of math and I now know I need 9 lbs [which happily is the exact weight of my ss plate!]

The result is that you can descend as slow or as fast as you like and can stop at any time.

Like to hook up the drysuit hose when you realize you forgot as your eyes start to bulge at 60 feet.

 

[Dryglove]

MikeFerrara once bubbled...
This has been addressed often here but it's important.

You need to be neutral with a near empty tank AT THE SURFACE. For those who say neutral at 15 ft...when wearing a wet suit, it will expand and become more buoyant as you ascend right? If your neutral at 15 ft you'll be buoyant above that. Don't you want to be able to control your ascent all the way to the surface?

As to the original post and the question about descent speed...

With a full tank you be a few pound negative. However you should be able to descend as fast or as slow as you want. One of the bad things new divers seem to be tought is to let all the air out of the bc to descent and the result is an uncontrolled descent.

Let just enough air out so that you begin to descend as you exhale. As you descend and your suit and the air in the bc compresses you add more to compensate. The result is that you can descend as slow or as fast as you like and can stop at any time.

This is very good advice and changed my weighting a while back to reflect what mike just said. I was very guilty of doing a nice controlled ascent to 15ft, do a 3 min safety stop and shoot to the surface. I now do a 3min safety stop at 15ft and do a very, very slow ascent the last 15ft to the surface. I have also slowed down my overall ascents all together incorporating some deep stops on deeper dives and feel much better after a dive.

Like to hook up the drysuit hose when you realize you forgot as your eyes start to bulge at 60 feet.

Yikes, that could be very uhm.... uncomfortable

 

[Warren_L]

BFM, also keep in mind that it works the other way too - as you are ascending the neoprene will expand and you will become more buoyant, so as you descend, the neoprene will compress and make you less buoyant so your descent rate will increase. You need to compensate by adding air to your bc. It is good to do this periodically so you don't scramble as you approach the bottom to establish neutral buoyancy.

 

[BFM]

did a dive this evening and every thing went well, descent was good, and this time no ear clearing problems, ascent was slow and controled, was using 10# of weight. i need to do more dives with my new equipment to get use to it.
many thanks for all the replys and please add more if there is anything else you think of. again thanks.

 

[Warren_L]

Once you get more comfortable with your gear and with diving, you should be able to lose a bit of your weight. Good work!

 

[ssdiver2003]

who really cares bout fast or slow descent / ascent...your weight divided by 10 plus 8 lbs will give you the aprox. right weight you will have to use on your belt..

 

[Doc Intrepid]

who really cares bout fast or slow descent / ascent...

All divers should care about ascent rates.

Descent rate can vary significantly. Ascent rate, on the other hand, can be critical. Ascent rate can influence the formation of microbubbles.

Even when diving within no-decompression limits, it is prudent to ascend at rates not exceeding 30 feet per minute.

Ensure you are properly weighted to allow yourself to ascend at a slow rate with complete control.

Doc

 

[donacheson]

MikeFerrara once bubbled...
This has been addressed often here but it's important.

You need to be neutral with a near empty tank AT THE SURFACE. For those who say neutral at 15 ft...when wearing a wet suit, it will expand and become more buoyant as you ascend right? If your neutral at 15 ft you'll be buoyant above that. Don't you want to be able to control your ascent all the way to the surface?

While you're precisely correct, IMHO there's no practical difference between being neutral with an empty BC and near-empty tank at 15 feet or the surface. Wet/dry suit compression is the only issue.

If a line is available for a safety stop, it can be used to control one's ascent to the surface. While diving in the tropics, wet suit compression is negligle. Even with a heavy neoprene suit on, gentle swimming or controlling one's breathing can easily accomodate the increase in buoyancy associated with wet suit compression above 15 feet.

 

[Don Burke]

ssdiver2003 once bubbled... who really cares bout fast or slow descent / ascent

I certainly do. An AGE could ruin your whole day and a considerable number of days after that.

ssdiver2003 once bubbled... ...your weight divided by 10 plus 8 lbs will give you the aprox. right weight you will have to use on your belt..

That's not valid in most cases. I've worn anywhere from zero (and still was overweighted) to about 40 pounds.

 

[Don Burke]

donacheson once bubbled... quote:
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MikeFerrara once bubbled...
This has been addressed often here but it's important.

You need to be neutral with a near empty tank AT THE SURFACE. For those who say neutral at 15 ft...when wearing a wet suit, it will expand and become more buoyant as you ascend right? If your neutral at 15 ft you'll be buoyant above that. Don't you want to be able to control your ascent all the way to the surface?

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While you're precisely correct, IMHO there's no practical difference between being neutral with an empty BC and near-empty tank at 15 feet or the surface. Wet/dry suit compression is the only issue.

If a line is available for a safety stop, it can be used to control one's ascent to the surface. While diving in the tropics, wet suit compression is negligle. Even with a heavy neoprene suit on, gentle swimming or controlling one's breathing can easily accomodate the increase in buoyancy associated with wet suit compression above 15 feet.

I think this is more a matter of grammar than practice.

I weight to hover on my lungs at 10 feet with 400psig. Many people weight for empty lungs.

The difference in weight between 500psig and the minimum pressure a regulator can operate at is going to be around a pound even with fairly big tanks.

My wetsuit is about 13 pounds positive at the surface. That would be about 11 pounds at ten feet.

Coming up that last few feet two or three pounds positive isn't going to be a crisis.