We have recently finished making our own cannister lights. I have attached
some photos and drawings for the mounting bracket. The bracket is secured
to the side of a scuba tank, using a standard cam strap and the battery
cannister is secured to the bracket by two SS hose clamps.
The cam strap has a series of slots and an adjustment screw so it accommodates
from a 70 to 120 cu ft tank range quite nicely. The SS metal band does
not stretch like the nylon tank straps do. I have single 80's and twin
70's, so it works well for me. We tried the cannister in front, but didn't
like it. We found it hung too low and bumped into things.
We chose to put the switch in the cannister because there was lots
of space. We found the small switches (compact) had too low horse power
rating and would weld on from the in rush current. The unit I photographed
has a 1 3/4 horse power DC rated switch, that work well. By placing the
cannister switch down, I can reach back under the cannister and switch
on/off easily. I will be changing the handle, to a larger SS model to act
as a guard over the toggle switch.
The batteries (accumulators) are 2x 6V 10Ah lead acid gel cells.
2 orings would be better, next generation we will have two.
The pictures are also available in larger size if necessary.