How to find the Optimal Height for Sidemount Cylinder Bands
by Andy Davis
Here is a quick ‘how to’ guide to configure the optimal height for your sidemount cylinder bands. This method assumes you are using LOOP bungees. It’s correct for either steel or aluminum cylinders, whether you use waist D-rings or a buttplate/rails for steels.
1) Measure from the armpit (which is where you’d want your valves) down to the mid-point of the waist belt (or buttplate rail, if you’re using that with steel cylinders). Armpit to attachment point is the measurement needed.
Note: if using the waist D-rings for attachment, the harness should be sized to place the waist belt down low on the hips… this is especially important for shorter divers – as you need to maximise the distance between the armpit and waist belt to prevent the band being too high on the cylinder. If the band is too high, it will be above the balance fulcrum of the cylinder and it will be impossible to keep the tank in trim.
This is why fully adjustable harness systems, utilizing lumbar/shoulder plates with an adjustable spine webbing strap are optimal. If your sidemount rig isn’t adjustable in length, such as with a soft or hard backplate, then you’ll struggle to make the adjustments necessary to achieve an optimal outcome.
2) Measure the same distance down from the top of the tank valve. This is the correct positioning of the cylinder band.
This locates the valves/regulators up under the armpits. If the band were positioning any lower, it would cause the valves too extend forwards of the shoulders. This would also push the valves lower, in turn pivoting the base of the cylinder upwards. That would ruin any chance of acheiving proper cylinder trim.