Steel VS Aluminum Backplate

[RTodd]

Uh, I don't think that's what DIR sells at all. If you took that to it's extreme, then a recreational diver would be using the same rig as the WKPP cave diver, and we know that's not the case.

I have one rig for recreational, and one for diving doubles also. Each has it's own requirements. But, within each sub-specialty, the rig stays pretty much the same.

Actually, it is the case assuming we are talking open circuit. The only thing that changes is the wing size and the number of tanks and regulators. You can use the same stainless plate that you use for a 3mm suit open water dives for double dives in AL tanks or when using mix in steel tanks. However, for convience reasons most people don't.

As you advance, always having a balanced rig generally dictates at least one stainless and one AL plate. For instance, when not diving mix with steel doubles most people need an AL plate even in a drysuit for freshwater dives - in order to have a properly balanced rig. More than one of each is convience. However, once you get to this point you have so much money invested in equipment, buying second stainless backplate that is permanetly set up for open water so you don't have to adjust it is just easier.

 

[detroit diver]

This isn't worth arguing about, but if you're changing wings, then you're diving a different rig. Same w/ regulators.

I can't use a SS plate on my twin 104's-it's just too heavy. But I do use it w/ my 3mm shorty as it balances perfectly. Has nothing to do w/ convenience at all.

I don't dive CC, so I can't comment on that equipment.

Actually, it is the case assuming we are talking open circuit. The only thing that changes is the wing size and the number of tanks and regulators. You can use the same stainless plate that you use for a 3mm suit open water dives for double dives in AL tanks or when using mix in steel tanks. However, for convience reasons most people don't.

As you advance, always having a balanced rig generally dictates at least one stainless and one AL plate. For instance, when not diving mix with steel doubles most people need an AL plate even in a drysuit for freshwater dives - in order to have a properly balanced rig. More than one of each is convience. However, once you get to this point you have so much money invested in equipment, buying second stainless backplate that is permanetly set up for open water so you don't have to adjust it is just easier.

 

[andrek]

I just ordered a Dive Rite Steel Plate with the 'Basic' (continues) strap and based on a few local reccomondations got a steel backplate instead of the aluminum one. Well the more I think about it - I question my decision. I usually dive with a 3mil suit, and a 3mill vested hood and I had used 12 pounds of weight on my belt. This is in salt water

Now Im wondering if Ill be overweighted with the steel plate and a 100 or 120 Steel tank ...........

As your diving in a wet suit you shouldn't be diving with steel tanks.

You will have to get your weighting sorted out no matter wether you ordered a steel or ali backplate.

 

[mossym]

I just ordered a Dive Rite Steel Plate with the 'Basic' (continues) strap and based on a few local reccomondations got a steel backplate instead of the aluminum one. Well the more I think about it - I question my decision. I usually dive with a 3mil suit, and a 3mill vested hood and I had used 12 pounds of weight on my belt. This is in salt water

Now Im wondering if Ill be overweighted with the steel plate and a 100 or 120 Steel tank ...........

As your diving in a wet suit you shouldn't be diving with steel tanks.

You will have to get your weighting sorted out no matter wether you ordered a steel or ali backplate.

that's twice in 2 days that's been said..it depends whether or not he can be bouyant with the steel tank and wetsuit, if he still needs extra weight with the steel tank to get down he should be fine...i dove a steel tank for ages in my wetsuit, that said it's a full7mm with a 7mm hooded vest, so i still needed 24lbs of weight to sink..

edit: there i go again posting in the DIR forum without realising...excuse me folks..

 

[jonnythan]

that's twice in 2 days that's been said..it depends whether or not he can be bouyant with the steel tank and wetsuit, if he still needs extra weight with the steel tank to get down he should be fine...i dove a steel tank for ages in my wetsuit, that said it's a full7mm with a 7mm hooded vest, so i still needed 24lbs of weight to sink..

edit: there i go again posting in the DIR forum without realising...excuse me folks..

From what I gather, and I might be wrong (Lord knows it's happened before), wearing a thick wetsuit deep is what's really not DIR. The critical question is whether you can deal with a total buoyancy failure or not... it doesn't matter whether you have steel tanks and 10 lbs of lead or an aluminum tanks and 20 lbs of lead if you're wearing a thick wetsuit at 100 feet.. either way you're probably not in a balanced rig..

 

[mossym]

true, like i said, i didn't realise it was the dir forum, but now that you mention thats an excellent point..

 

[jonnythan]

true, like i said, i didn't realise it was the dir forum, but now that you mention thats an excellent point..

OT, but.. DIR or not, it's a critical question for every diver, period. Can you deal with a total buoyancy loss at the depth at which you're diving? Do you even know?

What if that pull dump comes apart at 100 feet, and you're suddenly hopelessly negative? Is your answer to just dump weight and rocket to the surface uncontrolled?

Anyway, back to the discussion at hand..

 

[mossym]

something to check on the next dive..

 

[Charlie99]

wearing a thick wetsuit deep is what's really not DIR. .......... whether you have steel tanks and 10 lbs of lead or an aluminum tanks and 20 lbs of lead if you're wearing a thick wetsuit at 100 feet.. either way you're probably not in a balanced rig..

That really gets to the heart of the matter! It's the clearest statement of the problem I've seen in all of the various "steel tanks and wetsuit" threads.

 

[RTodd]

That really gets to the heart of the matter! It's the clearest statement of the problem I've seen in all of the various "steel tanks and wetsuit" threads.

Yes and no. The bigger problem with steel tanks and wetsuits is they are a few pounds negative when empty and are really negative when full. By contrast, an AL tank swings from a few pounds negative to a few pounds full. So, assuming you need 4lbs to offset the bouyancy of your wetsuit, you would need 6lbs of lead when wearing an al80 to be neutral (2lbs positive when empty) at the end of the dive meaning you start off being 4lbs overweighted due to the air in the tank. In a steel tank that is say 3 lbs negative when empty, you would only need one pound of extra weight to offset your wetsuit and would start off being 4lbs overweighted (actually more since they typically hold more air) due to the air in the tank. As the amount of air in the steel tank and the how negative the tank is when empty increases, the amount you are overweighted at the start of a dive increases even more. The compression of a wetsuit, and subsequent loss of bouyancy increases this problem even more on deeper dives, particularly with a thicker wetsuit.

These numbers are not that big of a deal when talking about single tanks, but when you are talking about doubles, they are extremely material. Even so, if you are really striving for the safest rig possible, the AL80 when diving with a wetsuit is generally the best way to go. (Drysuits represent redundant bouyancy and steel tanks are fine as long as you still keep your rig balanced.) As a complete aside, as your breathing rate improves, an al80 will easily take you beyond the 32% no-deco limits on anything deeper than a 60' dive.

Edited to correct the numbers. As long as you have at least 4 lbs of ditcable weight with an al tank you can always be neutral. With a steel tank, you do not have a way of making yourself neutral.