Cam Band Tension Pads

[cool_hardware52]

These are Tobin's Cam Strap Tension Pads in the image <edit: to the left of the cam> https://www.deepseasupply.com/index.php?product=43

There is also a rubber protective pad under the cam band in the image, but that is just to prevent scaring Aluminum cylinders when I travel. Oddly enough, that pad under the cam does very little to increase friction when wet. Tobin's pads do a much better job than just that piece of rubber.

Several of us actually did some shop experiments of holding power when preparing the http://www.scubaboard.com/forums/bu.../391300-cam-buckle-assembly-instructions.html We took a cylinder with intentionally loose bands and jerked them by letting them drop about 3' before the overhead rope stopped them mid-air. In this case we were testing the efficacy of two bands versus one, but we were left with the impression that the pads helped.

In any case, if you don't use them this way you should try it. They have worked well for several years on a Freedom Plate. I especially recommend them to people with physical limitations that makes using a highly tensioned cam band uncomfortable regardless of back plate or BC.

Akimbo,

The "wedge blocks" which are the part in question, will work only with a DSS Back plate. Plates with different geometry in the center channel (essentially every other plate on the market) don't compress the Wedge Blocks. That's why we don't offer them for purchase separately on our website.

The Wedge blocks provide a couple of benefits, one is keeping the cambands in place relative to the back plate, so they don't rotate around the tank. The second and far more important benefit is providing something compliant to compress when the cambands are closed.

The "Cam Strap Tension Pads" will work with most BCs / Back Plate and Wings. These are placed between the band and the cylinder. These too work by providing something that will compress as the cambands are closed. The Tension Pads don't really work via friction between the elastomeric Pad and the tank.

It requires very little tension in a camband to retain a tank, but there has to be some tension. Because camstraps stretch, and tanks actually become smaller as the pressure drops having some element in the system that maintains some preload on the strap helps quite a bit.

The analogy I use is two pieces of steel bolted together via two bolts. The first short bolt bolt as tight as one can get it with their fingers and the second bolt is quite long and a compression spring has been placed over the bolt. As the longer bolt is tightened the spring is compressed.

Pretty easy to see that the first bolt need only loosen a fraction of a turn and there is zero clamping force. The second bolt can loosed many turns and there will still be some force holding the plates together. Both the Cam Strap Tension Pads and the Wedge blocks are the "Spring" in the system.


Tobin

 

[Akimbo]

OK, different parts. I stand corrected. How different are they? Meaning could the “Wedge Block” be moved to the cam bands to function like “Cam Strap Tension Pads” in order to solve tddfleming’s problem? They “look” the same from the photos.

I can understand the back interference. I have seen divers that can’t use wing nuts to secure their plate to doubles for the same reason. Needless to say, they don’t have to pay extra for spine pads in their wetsuits like me.

 

[cool_hardware52]

OK, different parts. I stand corrected. How different are they? Meaning could the &#8220;Wedge Block&#8221; be moved to the cam bands to function like &#8220;Cam Strap Tension Pads&#8221; in order to solve tddfleming&#8217;s problem? They &#8220;look&#8221; the same from the photos..

Very different. The wedge blocks only work in the center channel of a DSS plate.

Tobin

 

[OkByMe]

I tried those once. Reese makes what is called a sure-step pad that goes on boat trailers and boats that are different sizes and traction configurations. I replaced a pad on my boat trailer that had bad adhesive and used the one I took off to make cam band pads. They will compress under some tension, but do not get loose at depth, they also do not tear up. If cut to the right length and put on the buckle side, it will keep the band from sliding around the tank.