Just received the Fundamentals book

[detroit diver]

Consider finding a shop that promotes GUE training and establishing a relationship. Perhaps get on the shop's local mailing list.

If it's DIR you're interested in, beware of just assuming that because someone's wearing a backplate that they know anything about it. Many don't ... even some who claim they do.

My advice ... go to the source. At an LDS who offers the training you'll find the real deal ... and in my experience, you'll find people who are willing to mentor. One of the advantages of the DIR approach to diving is that it's easy to find people who are into doing dives simply for the sake of practicing skills.

... Bob (Grateful Diver)

Bob's advice is good. Make it easy on yourself and give GUE a call and ask them who's in your area. www.gue.com or www.extreme-exposure.com

 

[JustJoe]

My FredT plate came with a harness kit that included everything you needed ... but it wasn't assembled.

FWIW - Fred uses quality webbing, but it's extremely stiff. If you go this route, I'd recommend you soak the webbing in a solution of fresh water and fabric softener for a day or two to loosen it up a bit ... makes the assembly go a little easier.

... Bob (Grateful Diver)

I contacted him yesterday and he is sending me a price list. Started looking at wings on ebay. The wings on there are still more expensive then the bc I purchased. After I get my bp/w setup I will put my bc on there and see if I can recoup some of the cost.

Joe

 

[detroit diver]

You always dive your plan. Included in that plan is a concept called "rock bottom". It is an amount of gas that can get you and your buddy to the surface with all of the normal stops. You NEVER violate rock bottom, because at that point you have put both yourself and your buddy in potential jeopardy.

This brings the need for excellent gas management to the forefront. Most OW REC divers (like me) are trained that when you get to a predetermined PSI, then you ascend at a relatively slow pace and do your safety stop. If you add time to that wouldn't you need to also add the amount of air consumption to the equation? And if your air consumption changed on the dive due to whatever reason, do you now have to recalculate your SAC to know when to start your ascent? Or do you build the dive based around a gas consumption safety margin (meaning it should take x cf of gas so I am going to have x+y cf of gas)?

Maybe these are stupid questions.

Joe

 

[reubencahn]

And rock bottom is based on SAC rate that is double your normal to allow for stress-induced increase in breathing rate.

 

[kalvyn]

This brings the need for excellent gas management to the forefront. Most OW REC divers (like me) are trained that when you get to a predetermined PSI, then you ascend at a relatively slow pace and do your safety stop. If you add time to that wouldn't you need to also add the amount of air consumption to the equation? And if your air consumption changed on the dive due to whatever reason, do you now have to recalculate your SAC to know when to start your ascent? Or do you build the dive based around a gas consumption safety margin (meaning it should take x cf of gas so I am going to have x+y cf of gas)?

Maybe these are stupid questions.

No Joe, thse are excellent questions; ones that are rarely covered in OW/AOW and should be covered in OW, in my opinion.

I'll just give an example of a normal dive for me and my buddies. We do mostly shore diving, so we need to exit were we entered the water. So the first thing to know is your "rock bottom", which is the gas you always keep in reserve to get both you and your buddy back to the surface from the deepest part of the dive (no overhead diving, I'm talking straight recreational diving here). I dive a steel E8 119, and use a rock bottom of 700 PSI @ 100 feet salt water. So, I subtract 700 PSI before the dive even begins... if I gear up and my tank's at 3700 PSI, I now treat it as 3000 PSI.

The second thing to consider is turn pressure. Since we need to get back to where we started from, we'll turn the dive after we've used about half our gas (minus the rock bottom reserve). So my turn pressure on this dive is 1500 PSI + 700 PSI = 2200 PSI.

Also, as you come up shallower, your rock bottom needs decrease. So my and my buddy will spend a lot of time at 33 FSW and less, making up for time spent below 66 FSW. I will not have any problem running my tank down to 500 PSI or even a little less while I'm in 15 FSW or less, depending on the conditions that day.

This might seem complicated at first, but it's not really. It just takes practice. I dive the same tanks all the time, so I just "know"; I don't do any math during the dive or anything like that. I am not that good at math.

Jimmie

 

[JustJoe]

Rock bottom is calculated by doubling your sac rate and that of your buddies sac rate? This would make diving with someone who doesn't know what theirs is a piece of guesswork.

Rock bottom and turn point are both parts of gas management that I did not see in the book, is this tought in the fundies class?

Joe

 

[Soggy]

Rock bottom is calculated by doubling your sac rate and that of your buddies sac rate? This would make diving with someone who doesn't know what theirs is a piece of guesswork.

Rock bottom and turn point are both parts of gas management that I did not see in the book, is this tought in the fundies class?

Joe

Yes, it's taught in the fundies class. We just use a SAC of 1cft/min per diver. That's pretty conservative and makes the math easy.

 

[MXGratefulDiver]

Rock bottom is calculated by doubling your sac rate and that of your buddies sac rate? This would make diving with someone who doesn't know what theirs is a piece of guesswork.

Rock bottom and turn point are both parts of gas management that I did not see in the book, is this tought in the fundies class?

Joe

The book is just an overview ... there's lots of stuff in the class that you won't find in the book. That's one reason why the class is about 10 times more expensive than the book ...

It's worth it ...

... Bob (Grateful Diver)

 

[Henryville]

No Joe, thse are excellent questions; ones that are rarely covered in OW/AOW and should be covered in OW, in my opinion.

I'll just give an example of a normal dive for me and my buddies. We do mostly shore diving, so we need to exit were we entered the water. So the first thing to know is your "rock bottom", which is the gas you always keep in reserve to get both you and your buddy back to the surface from the deepest part of the dive (no overhead diving, I'm talking straight recreational diving here). I dive a steel E8 119, and use a rock bottom of 700 PSI @ 100 feet salt water. So, I subtract 700 PSI before the dive even begins... if I gear up and my tank's at 3700 PSI, I now treat it as 3000 PSI.

The second thing to consider is turn pressure. Since we need to get back to where we started from, we'll turn the dive after we've used about half our gas (minus the rock bottom reserve). So my turn pressure on this dive is 1500 PSI + 700 PSI = 2200 PSI.

Also, as you come up shallower, your rock bottom needs decrease. So my and my buddy will spend a lot of time at 33 FSW and less, making up for time spent below 66 FSW. I will not have any problem running my tank down to 500 PSI or even a little less while I'm in 15 FSW or less, depending on the conditions that day.

This might seem complicated at first, but it's not really. It just takes practice. I dive the same tanks all the time, so I just "know"; I don't do any math during the dive or anything like that. I am not that good at math.

Jimmie

This is a sincere question. In the above scenario, aren't you wanting to plan to get you and your buddy back from your furthest point on just your gas (planning for a potential failure of the buddy's equipment) and so you would be diving thirds minus rock bottom for a turn point?

I don't often shore dive and I am honestly trying to remember but I thought that if you had to return to the entrance point you needed 2/3 minus rock bottom. Maybe because you are shore diving versus boat diving you are viewing the rock bottom and a surface swim as the contingency exit strategy?

 

[MXGratefulDiver]

This is a sincere question. In the above scenario, aren't you wanting to plan to get you and your buddy back from your furthest point on just your gas (planning for a potential failure of the buddy's equipment) and so you would be diving thirds minus rock bottom for a turn point?

I don't often shore dive and I am honestly trying to remember but I thought that if you had to return to the entrance point you needed 2/3 minus rock bottom. Maybe because you are shore diving versus boat diving you are viewing the rock bottom and a surface swim as the contingency exit strategy?

Correct ... in an OW (non-overhead) emergency you ascend and return to your entry point on the surface.

... Bob (Grateful Diver)