Tank height strap for backplate?

[patrickusaf08]

I use a back plate and wing and when i first got it I to had the same problem. Now what I do is put two straps on i get the top one semi tight just so i can make minor corrections to it. Once corrections are done I go to the bottom band make that tight and secure it then go back to the top band undo the cam tighten it properly and then secure the cam.

 

[tbone1004]

once you set the cam bands for the tank diameter, the only time you should ever have to change them is if you change to a new tank diameter, especially if there is any sort of pad on them that will compensate slightly for any inelastic recompression. I.e. I haven't touched my STA in over a year, and put it on a tank last night and it is still tight enough to dive with.

The stock cam bands from Tobin do not have any sort of pad on them at all, this is fine for plastic cam buckles, but on metal it causes paint to chip off and scratch and makes things ugly. With pads it prevents that but also prevents slippage as the grips are quite wide and provide pretty good grip. When you remove the cam bands it will require you to do one of two things, either manually hold open the cam band *most plastic ones will actually lock in the open position when you open them all the way, this loosens the cam band over an inch*, or you will manually shimmy it up the tank to get it off. Either is acceptable and with grip pads and metal cam bands it is usually a shimmy, with plastic cams without it is usually lock it open and it will generally behave for you.

Yes the comment was mostly facetious and was proving a point, but there are many reasons not to want them. Here they are

Colossal PITA when switching tank diameters, the 8" tanks *surprisingly common for some recreational shops, they'll have AL80's for air and AL100's for nitrox*, move the valve half an inch farther away from the back and the crown profiles are also slightly different, 6.9" LP72's are the same but opposite moving the valve closer with a steeper neck profile, and steel tanks can have a slightly different crown profile to aluminum, so it is another strap to adjust and it is an irritating one to adjust.

Useless with doubles, but more importantly it flails around and is a lovely way to hook yourself on a wreck if it is flailing around as they are difficult to reliably tuck in.

Useless in sidemount obviously

Useless in rebreathers for the same reason

It is an equipment solution to a skills problem when you have two cam bands, and if you only have one it is a necessary evil, but conveniently for this discussion all "real" backplate style rigs have slots for two cam bands, so it is moot.

They exist for the last reason, they are a necessary evil with single band systems to keep the valve from running away from you when you reach back for it. When you have a properly set up backplate system, you will know where you need that band in relation to the crown of the tank. The break of the tank should be 1-1.5 inches above the mounting holes for doubles. One of the reasons I am a firm believer in STA's for new divers is that with most of them, the top cam band is centered on the mounting stud for doubles. The magic rule for doubles is the top band sits just below the break of the tank, so the cam band goes in the same spot for singles, without an STA you have to find out where that sits. DSS puts their cam bands very low on the plates which I think is more for the recreational community to allow them to have tanks sitting very low, but take your hand and figure out if it is a full hand width or less than a hand width between the top of cam strap slot and the mounting holes, when you figure out how much it is, just set the bc on the tank, get the height set using your hand *i.e. full hand from the top is where I want it so it there*, lock the top cam band down, then lock the bottom and you're good to go. It's quite simple to do even on a rocking boat.

 

[TSandM]

I'm scratching my head over this issue. For each tank I use, I have a pretty shrewd idea of where the cambands need to be to allow me to balance properly and reach my valve. I've really never noticed being annoyed by the tank slipping down. I have sometimes had one spin a bit and have to be repositioned, but it's still pretty minor. I have had the straps on other BCs get caught on the valve handle or stuck between the tank and the BC, and have to be repositioned. That is also a minor issue.

I'm really quite sure that no one makes an item like what the OP wants, so he may as well build one if he feels it would make his rig nicer to handle. Seems like a pretty simple DIY.

 

[Dhboner]

When I dove a back mounted single tank I marked the tank where I wanted the top of the upper cam band. Then I slid the rig on while holding the plate in position with one hand and closed the upper cam band with the other hand.

 

[Tony387]

I think like everything else, adjusting your rig...becomes much easier with experience. When I first began diving, I remember fumbling with my BCD and tank in an attempt to get it just right. Now, throwing my bp/w on a tank of any size, and adjusting two cam bands, takes a matter of seconds. Before you know it, it will be a non-issue.

 

[eelnoraa]

I actually understand OP's issue. I had the same feeling when I first switched to BP/w. I think the slip OP is talking about is NOT after the cinching down the band, but during the process of attaching the tank. You can hold the bp/w by should strap using one hand and close latch with other, but it will be easier if the bp/w can have some thing to hold onto the tank neck, so I can just work on the cam strap without worry about the plate shifting up or down with respect to the tank. This is especially true if you use cam band like highland or scubapro, where the cam can open up entirely for easy tank switch. But this was never a big enough of an issue for me to do something about it. I think using 1" webbing is kind of messy. If I find a easy and clean way to do this, I will definitely give a try.

 

[ams511]

Tobin sells a wedge pad thing that does the same, but says for non DSS products, so might be worth sending him a note asking about. If your cam bands don't have any sort of grippy pad on them, that's your real problem and is better solved with getting grip pads or new cam bands.

Actually I think you have this in reverse, The wedge blocks are for DSS products because they slip into the channel of the backplate. DSS also makes a cam tension pad for non-DSS rigs. I presume the reason they say for non-DSS rigs is the fact that DSS rigs really don't need it because is already has wedge blacks.

Octogrips, as all things Halcyon, are expensive at $11 each. DGX sells a cheaper pad for less than $2.00 each.

 

[stuartv]

Actually I think you have this in reverse, The wedge blocks are for DSS products because they slip into the channel of the backplate. DSS also makes a cam tension pad for non-DSS rigs. I presume the reason they say for non-DSS rigs is the fact that DSS rigs really don't need it because is already has cam tensioners.

Octogrips, as all things Halcyon, are expensive at $11 each. DGX sells a cheaper pad for less than $2.00 each.

I believe tbone was actually talking about the cam tension pad. At least, that was what I understood. But, I may have assumed incorrectly. Of course, my rig does already have the DSS wedge blocks that the cam straps go through on the front side of the plate, in the plate channel.

Do other BP setups not have those wedge blocks? Maybe that's part of why my experience seems a little different than others. With those wedge blocks compressed, that means that when I open the cam buckle, those wedge blocks decompress some, taking some of the slack out of the open cam band. Thus, possibly explaining why my cam bands might not be as easy to slip off a tank as others?

---------- Post added March 26th, 2015 at 10:30 AM ----------

Also, the more this thread continues, the more I think that I am probably somewhat creating my own problem by putting too much effort into getting the cam bands tight. In other words, I think I may be getting them way tighter than they need to be. And the struggle to do that is always where my twisting and slipping down occurs.

If other BP setups don't have those rubber wedge blocks on the front side of the BP, in the channel, for the cam bands to go through, then I can see where they would benefit from the DSS cam tension pad - and also where people without any of those compression pads would need to really pay extra attention to getting their cam bands really tight.

I picked up somewhere along the way that you need to wet your cam bands and then make sure they are really tight. And, as I explained before, I have often not been able to wet my cam bands first, so I've always been paranoid about getting them EXTRA tight when dry. Maybe the specific rig setup I have I just don't need to work THAT hard at it. 'Cause if I don't, then I think a lot of my problems on this just disappear.

 

[ams511]

I suppose I could do it just using a piece of cave line tied into a loop, but that wouldn't be as convenient if I happen to be switching between 7.25 and 8" tanks.

Cave line would be the cheapest and you could always make two loops. One for 7.25" tanks and one for 8.00 tanks. However, I am wondering if the BC was assembled correctly. My experience with eBay used BP/W is that they are usually misassembled in some way.

 

[Lorenzoid]

. . .
Do other BP setups not have those wedge blocks? Maybe that's part of why my experience seems a little different than others. With those wedge blocks compressed, that means that when I open the cam buckle, those wedge blocks decompress some, taking some of the slack out of the open cam band. Thus, possibly explaining why my cam bands might not be as easy to slip off a tank as others?

---------- Post added March 26th, 2015 at 10:30 AM ----------

Also, the more this thread continues, the more I think that I am probably somewhat creating my own problem by putting too much effort into getting the cam bands tight. In other words, I think I may be getting them way tighter than they need to be. And the struggle to do that is always where my twisting and slipping down occurs.

If other BP setups don't have those rubber wedge blocks on the front side of the BP, in the channel, for the cam bands to go through, then I can see where they would benefit from the DSS cam tension pad - and also where people without any of those compression pads would need to really pay extra attention to getting their cam bands really tight.

I picked up somewhere along the way that you need to wet your cam bands and then make sure they are really tight. And, as I explained before, I have often not been able to wet my cam bands first, so I've always been paranoid about getting them EXTRA tight when dry. Maybe the specific rig setup I have I just don't need to work THAT hard at it. 'Cause if I don't, then I think a lot of my problems on this just disappear.

From what I recall--and Tobin could very well chime in--DSS includes the wedge blocks because the cam buckles are plastic. Closing the cam buckle compresses the wedge blocks, and the added tension is enough to help the cambands grip the tank tightly but not so much as to potentially break the plastic cam buckle. In contrast, a camband with a metal buckle could be closed extremely tightly without damaging the buckle, and would eliminate the need for the wedge block. But for whatever reason (cost?), DSS prefers plastic cam buckles, and so includes the wedge block to make up for the inability to crank down hard on the buckle.

I have rarely had a problem with tank slippage on my DSS rig. The only time my tank started slipping was when I had a long walk between the gear-up area and a shore entry. A tank doesn't need to be super-tightly gripped to avoid slippage except maybe in circumstances like that. Once underwater, the wet bands hold the tank just fine.