Tank Bonking??

[rkj1969]

I'm just a newbie using rental stuff right now, and I have a lot of trouble with the tank bonking me in the back of the head if I look forward or up. I have have tried a couple of different kinds and sizes of vests, trying to be sure it doesn't ride up around my ears.....and I adjust the top tank strap just as high as it is possible to....

It seems like all the tanks are the same - so I'm wondering if it's the fit of the BC causing the problem? or do I have some wierdly mis-shapen head?

I want to buy my BC soon (all signs are pointing to the Zeagle Zena) but I'm not sure if there's some fit consideration contributing to the bonk-a-bility of my setup that I should be weighing into my decision....

what do you think?

[petronius]

It's probably not the tank so much as the reg hitting you. I find that when I use my reg on a 7.25" diameter tank (think that's the size of an HP100) I get hit in the head unless I position the tank in a very low position that ruins my trim. So, I stick with my fatter LP tank.

You could try different reg designs that don't extend as far out from the valve, or use fatter tanks...

[Okc_diver]

It sounds like the tank is too high in the bcd. Try putting the tank a little lower in the bcd and you should not have that problem.

[Diver Kat]

I would often find that I would hit my head if I didn't get the tank straps as high as possible on the tank and if my reg's first stage was set off a bit. Thought it also might be partially caused by my being short as well. So I just have to be careful that I get things lined up right. Good thing about a Zena is it has 2 straps so I can put the top one right at the edge of the slope and not worry about the tank getting loose since the bottom strap is there. (Although I've never had the top strap slip anyway.)

[rayaa3]

My wife has this same problem. She is 5'7" and wears a medium bcd. If she wears her tank strap where I wear mine, she complains about getting bonked in the head. I tend to assemble her gear for her, so I simply moved the tank lower on the bcd (move the strap up). This gives a very funny fit, especially when walking around at the surface (almost like her tank is dragging behind her) but in the water she's happy. Since she doesn't shore dive, it's not like she walks around with the tank on her back much anyway.

My suggestion is the same as others, experiment with tank position. My wife was a much happier diver when she quit getting 'bonked'.

Ray

[din]

have you tried growing a longer neck? sometimes the most obvious solution is also the correct one.

[Vercingetorix]

I had that problem. I need to wear the tank up high in order to adjust trim.

The solution: turn the tank about 45 degrees to the right. This moves the reg housing off to the side. There is nothing in the Scuba Rules that says you MUST have the reg directly behind your head.

I also have two cam straps. The first cam strap is about 1 1/2 to 2 inches below the tank shoulder, AKA the "curve".

[Diver Kat]

My wife has this same problem. She is 5'7" and wears a medium bcd. If she wears her tank strap where I wear mine, she complains about getting bonked in the head. I tend to assemble her gear for her, so I simply moved the tank lower on the bcd (move the strap up). This gives a very funny fit, especially when walking around at the surface (almost like her tank is dragging behind her) but in the water she's happy. Since she doesn't shore dive, it's not like she walks around with the tank on her back much anyway.

My suggestion is the same as others, experiment with tank position. My wife was a much happier diver when she quit getting 'bonked'.

Ray

LOL ... that describes it exactly! I'm 5'4" so when I have the straps where I like them it looks like my tank is dragging down my back!

[Damselfish]

It happens, more to shorter people with shorter necks I assume. I'm an average height woman and run into this if I don't have my tank almost as low as possible. One thing about BCs with 2 straps, you generally can't get them as low as BCs with 1 strap, so watch out for that when you buy a BC. I have a Scubapro Ladyhawk, the SPs have one band which is very secure and allow mounting the tank a bit lower.

One drawback of lowering the tank is it may screw up your trim, depending on everything else, so you just have to play with things. Another problem is now the tank will probably be hitting you in the butt which is also annoying. One way to fix that is to dive with shorter tanks, so see what they have for rent, and take it into consideration if you buy your own tanks. Look at steel tanks which are shorter and have other advantages for most people, though they're more expensive. If you're renting, many places that have mostly the common (and cheap) AL80s will also have some AL63s, which are nice if your air consumption is decent enough, at least in comparison to your buddy.

Only you can answer the question about fit - when the tank (actually the reg) is hitting you, is the BC still where it should be?

If you buy a reg, you may want to take this into account, some may stick out further than others. I now have a Aqualung Mikron, I didn't buy it for this reason but the first stage is small and I'm sure it helps. Some first stages you can flip "upside down" (also rearranging the hoses) and it will change the position of the part that sticks out most. I think flipping a reg from "normal" will tend to make the head banging problem worse, but it's just another option to keep in mind.

[wgt]

Did I accidentally stumble into Man Laws?

My wife was a much happier diver when she quit getting 'bonked'.