Proper weighting question

[revid]

I did a search but wasn't able to find an answer to this question, so forgive me if it has already been addressed somewhere else......

I am about to purchase my first doubles setup. I will be diving dry with ss b/p, steel doubles, etc. I know that with the addition of items like this that most divers need little, if any additional weight. My question is about weighting, or maybe more appropirately, buoyancy. So here goes...

1. We all know the test for buoyancy taught in the ow courses (floating at eye level) but is that the same that you would use diving hog?

2. As with most recreational divers it has been ingrained in me that I need ditchable weight...is that really necessary?

3. What if my setup isn't enough and I do need additional weight, what is the best way to add it?

As I'm sure you can tell from my questions, I'm new to this and any help would be appreciated.

Thanks

 

[donacheson]

I did a search but wasn't able to find an answer to this question, so forgive me if it has already been addressed somewhere else......

I am about to purchase my first doubles setup. I will be diving dry with ss b/p, steel doubles, etc. I know that with the addition of items like this that most divers need little, if any additional weight. My question is about weighting, or maybe more appropirately, buoyancy. So here goes...

1. We all know the test for buoyancy taught in the ow courses (floating at eye level) but is that the same that you would use diving hog?

... /QUOTE]

Minimum weight is that needed for you in all your gear to be neutral just beneath the surface with an empty BC, near empty tank, and breathing normally.

Weighted to float at eye level with an empty BC, empty tank, and full lungs might approximate minimum weight.

 

[Doc Intrepid]

I will be diving dry with ss b/p, steel doubles, etc. I know that with the addition of items like this that most divers need little, if any additional weight. My question is about weighting, or maybe more appropirately, buoyancy. So here goes...

1. We all know the test for buoyancy taught in the ow courses (floating at eye level) but is that the same that you would use diving hog?

No. For technical diving the goal is to be able to hold your decompression stops under worst-case scenarios. Therefore, you want to be able to control your ascent all the way to the surface under conditions where your doubles are nearly empty, your argon tank is nearly empty, and any deco bottles you've slung are also nearly empty. Spend some time in confined water, as noted above, empty wing, nearly empty tanks (all of them), and with your drysuit pretty tight. Make sure that you can hold 10'. Make sure you could hold 5'. While you don't want even 1 lb more than you need, its way better to be a couple lbs heavy than even 1 lb too light. (Trust me on this one...)

2. As with most recreational divers it has been ingrained in me that I need ditchable weight...is that really necessary?

No. If a technical diver has a problem, ditching weight and conducting an uncontrolled ascent to the surface will only make it much worse. Technical diving is, by definition, done in an overhead environment: either a tangible overhead (cave, wreck) or an intangible overhead (decompression obligation). Therefore, if you have a problem you cannot surface to solve it. You must solve the problem underwater. Ergo, ditchable weight is irrelevant - you couldn't ditch it if you had it. How would you thereafter control your ascent?

3. What if my setup isn't enough and I do need additional weight, what is the best way to add it?

With doubles you have basically two options. You do either one or both. Most SS plates weigh 6 lbs. You can either go with a heavier plate, or use a V-weight, or both. Heavy plates come in 9, 12, and 15 lbs. V-weights are often sold in either 8 or 11 lbs, or you can pour your own to any weight you'd like. V-weights ride on the bolts, nestled in between your double tanks, between the tanks and your wing.

As I'm sure you can tell from my questions, I'm new to this and any help would be appreciated.

You may find it easiest to locate a mentor in your area, and work with someone who has already gone through this same transformation. Mentors can save you significant grief and expense.

Best of luck,

Doc

 

[waynne fowler]

I did a search but wasn't able to find an answer to this question, so forgive me if it has already been addressed somewhere else......

I am about to purchase my first doubles setup. I will be diving dry with ss b/p, steel doubles, etc. I know that with the addition of items like this that most divers need little, if any additional weight. My question is about weighting, or maybe more appropirately, buoyancy. So here goes...

1. We all know the test for buoyancy taught in the ow courses (floating at eye level) but is that the same that you would use diving hog?

2. As with most recreational divers it has been ingrained in me that I need ditchable weight...is that really necessary?

3. What if my setup isn't enough and I do need additional weight, what is the best way to add it?

As I'm sure you can tell from my questions, I'm new to this and any help would be appreciated.

Thanks

You need to be able to be neutral at 10' with no air in your BC or Drysuit using just your lungs for buoyancy control. Go to the water with 500psi in your tanks get all the air out of your drysuit and your BCD. Have a friend bring down some weights in 2lb bags. see if you can get underwater. If you can't take a 2lb bag and try again.. Once you can get underwater make it to 10' and attempt a hover. Take weights from your friend until you can maintain position while breathing normally. Normal breathing is important. You cannot underweight yourself so that you are forced to breath shallow, nor can you go the other way.. You must be able to breath completely normal.

When properly weighted you won't need ditchable weight as in the event of a failure you will only be swimming up the weight of the air in your tanks.

When you start positioning weight in your doubles you have a couple of choices, and depending on the BP/W you use you may or may not have more. The BP's made by Deep See Scuba gives you a few different weighting options. Anyway.. you can choose to store some weight behind the backplate in the V of the tanks.. You can purchase an actual v-weight or make one yourself. If you just need to gain a few lbs you may choose to eliminate the tank boots which add about 1lbs of positive buoyancy each.. Then later you'll have to readjust as you add things like a can light etc..

Hope this helps a bit.

 

[Bob Sherwood]

Check bouyancy at the beginning of the dive when you are the heaviest to be sure that with a loss of wing you still have the ability to get yourself off the bottom. Then again as advised at the end, with the ability to complete shallow stop. Only checking at the end is a common mistake made relative to weighting. Best, Bob

 

[revid]

Thank you all for the responses. I have a local instructor that I will be working with, but just wanted to get a head start if possible. I appreciate the info and I'll be heading to the pool now to try it out.

Thanks