Is there a technique to banging on a tank?

[Anna1990]

I have a metal pointer which I tried out for the first time on the trip I just took. Is there some technique for getting it to make a good sound on your tank?

I went after a couple of friends who were swimming away from everyone else when the DM wanted to move on and was banging my tank pretty constantly but they didn't hear me until I caught up to them.

Is there some technique to make it ring out better? Or maybe my friends were just ignoring me?!

 

[Doc]

If your buddies haven't yet "learned to hear", and that is an acquired skill, a hand grenade will not work. They're too busy diving...loss of senses induced by stress is very natural but not obvious.

If you gently tap your mask glass with your plastic flashlight, any DM should turn and look. They are relaxed, their sense of hearing has returned.

Stainless Steel muck sticks? I find them being used often quiet destructively as a walking stick (unknowingly and innocently, but devastating). If you want a banger, how about an aluminum snaplink carabiner? A multi use item, many DMs have them on their hand looking like brass knuckles.

There are a whole lot of noises over a reef structure, it's really rather a droning, crunching, crackling cacophony. In fresh water, it's positively silent in comparison.

Practice this hearing skill by planning "signal tests" in advance, before the dive.

 

[Anna1990]

Hmm interesting, makes sense I guess as this was one of their first dives in the ocean after qualifying in fresh water. I hadn't thought that fresh water would be much quieter but you're probably right - the reef is noisy!

I keep my pointer in my BCD pocket or in my hands (and not jabbed into the reef) but, for what I want it for some other device may be better I guess. I did enjoy pointing my stick at the anemonefish this trip though and seeing how they reacted.

 

[diversteve]

a DM on a boat once had an old box wrench on a short cord on his BC.

When he banged it, everybody heard it.

Your pointer may not have enough mass.

I was on a boat in Maui once where they showed us the emergency recall - a ball peen hammer they banged on the ladder. We certainly would have heard it.

 

[g1138]

The shorter but especially heavier the object, the louder the bang. Try a double ender bolt snap or a 9/16in wrench.
Seriously, the wrench is the best.

Pointers generally flex a little bit so you don't get a solid hit and the lack of mass in it doesn't create a loud bang.

For technique, you'll want to have your hand right next to the tank and only use your wrist motion to bang away. It makes the impact faster and sharper than using your whole arm to swing.

 

[northernone]

For knocking technique the best I know is be closer to your buddy.

If you're far enough away from your buddy to need to bang. You don't have a buddy and are effectively alone. (Unless they are unusually hard of hearing)

A loud grunt through the reg work when a buddy is close enough to be a useful buddy. Or even a knuckle against the tank.

If you're needing a hammer it's likely the buddy is dangerously far away. Unless you're trained and diving solo.

To directly answer... Using a pointer as a battering ram against the tank held loosely works fairly well with a quick flick of the wrist. One or two rings can be plenty otherwise it's a buddy technique issue.

Keep your anemones closer.
Cameron

(Tank banging is horrible annoying to everyone within earshot who doesn't want/need the noise disturbing their dive, that can be a long way underwater, especially if someone is enjoying the sounds of the reef)

 

[Wookie]

If I need a noisemaker, a reef poker isn't it. I carry a suicide clip snapped onto a d-ring as Doc described, or take a handful (OK, 4 or 5) of 1/4" stainless nuts and put them in a 3" section of 3/8 or 1/2" PVC pipe and glue caps on each end. If you shake that, it makes a noise unique to you and gets someone's attention.

But as it turns out, I don't want anyone's attention, nor do I give anyone mine unless they are dying and come tackle me. My wife says I'm a lousy buddy. I wear the term proudly. If you dive with me, be prepared to dive alone. I can't wait until I'm fully deaf. I have missed a number of whale sharks and manta rays.

 

[CamC]

Is there some technique to make it ring out better?!

Isn't this a PADI specialty? Trick missed, PADI.

 

[Ana]

Before "banging" anything, please keep in mind that you are already noisy enough by your presence. No need for greater noise pollution but trying to figure out what would be louder.
Emergencies are a thing, but someone not paying attention? oh no... lessons need to be learned (one way or another)

 

[Neilwood]

Personally I use the boltsnap that my lights (2 small identical flashlights) are attached to the D rings with. During the dive I will generally have the light in my hand so it is easy to flip it round, hold the boltsnap and bang the tank.

One thing to be aware of though is hoods - I am near deaf in mine despite having perfect hearing without it. If you need a hood , be prepared to have to either bang a lot louder or develop another method of signalling (torchlight?)