cool_hardware52
Contributor
Stephen Ash:There is absolutely no reason why your weight plates should not be used with doubles. If the bolt length is right they will fit just fine. Even with the weight plates on the back side of the backplate there is still plenty of thread to grab and still have bolts that are within the plane of the cylinders.
MANY divers use AL80s twinned up. These make a great little set. MANY divers use these cylinders with a drysuit. It is a well known fact... and sometimes a real unfortunate one... that this combo needs extra weight. This is the perfect situation to use a V-weight or a extra heavy backplate. Your weight plates are a great solution for this problem.
Stephen, Who designed these goods you or me? It is beyond arrogant for you to tell me what my goods should or should not be used for. Simply amazzing.
You want to be objective, but you have seen and used only a tiny fraction of what we make and sell. How does that qualify you to tell me how my goods should be used?
While it might be true that double 80's need extra ballast we can't be all thing to all people. Because a combination of goods is possible doesn't mean it's a good idea.
Using the weight plates with doubles creates several problems. You need longer bolts, so long infact that they may project above the plane of the tanks. I consider this unacceptable. It leaves the bolts subject to damage when the tanks are not secured to a backplate. If you make the band bolts long enough to accomodate a backplate that's effectively 1/2 thick, and then use these same tanks on a plate without bolt on plates you run the risk of damage to the exposure suit.(sound familar?) It is exactly these problems I seek to avoid by not using the bolt weight plates with doubles.
Stephen Ash:I'm sure that you know that I know that, too.
Stephen, I suspect you know a number of things. If this was private one to one discussion, there is much I hope I would not need repeat. This is a public forum. I can't assume what others "know". Backplates and wings are a pretty simple device, but my consistent experience has been that people who have not ever used or assembled a BP&W have very little real idea how they work, how they assemble, what combinations are possible, and what the pros and con's of each combo might be.
When I answer a question I always try to keep in mind the other readers who may not know what you do.
Stephen Ash:Metal to metal. There's no squishing these together any closer. Ya know... sometimes an 1/8" is all ya need. But if ya don't have it, then ya don't have it. It simply won't work. Not to my satisfaction, at least.
It's not metal to metal, not at all. The plate contacts the wing and tanks exactly where the harness weaves through the plate. The metal of the back plate doesn't even touch the wing or tanks. If the harness is "puckered" a bit it can hold the plate off the tanks a bit. In most cases if you lean on the plate you'll get a bit more bolt to project through.
Stephen Ash:I holed my suit with the longer bolts and I've heard of other guys that holed theirs in the same way. It can happen. I hope that no one else holes their suit. But it would be wise to listen and learn from those that have made the mistake already. There's no reason not to size your bolts appropriately. Not doing it exposes your suit to some added risks.
Agreed. With our Backplates, used the way I recommend, do not require excessively long bolts, 1/4" to 3/8" below the plane of the tanks works fine. This is the way almost all doubles I've ever encountered are set up. Bolts of this lenght are not a risk to exposure suit, when used with our plates, or others.
Stephen Ash:The first two pics show your plate with the bolt that I use for my other plates.
The second two pics show your plate with the slightly longer bolt.
You'll notice that there is no way to thread a wingnut on the bolt in Pic 1.
Exactly, that's one reason why the weight plates are not recommended for use with doubles.
Stephen Ash:You'll also notice that if you use a washer ang a split ring that you will only have a few threads grab in the setup shown in pic 2. That's not enough for my liking.
There's plenty of thread if you use the DSS delrin thumbscrews, no need for flat washers and lockwashers, use the right tool for the job. http://www.deepseasupply.com/page13.html
Stephen Ash:However, if you look at the setups in pics 3 and 4, things work perfectly... whether the weight plates are front or rear mounted, there is plenty of grab for the wingnuts. Yet these bolts are still behind the plane of the cylinders. This shows that these weight plates can be a great way to offset the inherent bouyancy of AL80s. There's no reason in the world not to recommend using your plates for this purpose. No reason except that the bolts MIGHT be a little long if one should choose to slap on another more typically designed plate from another manufacturer.
Let's see here. No reason not to use our goods contrary to our recommendations except that it might lead to the very problem you experienced....... Sounds like a pretty good reason to me.
Suggesting people change bolt lenghts on doubles that they may not even own opens a huge can of worms. Having bolts on doubles that extend beyond the plane of the tanks is a damned PITA. First time you lay the tanks down, or slide them into your pickup bolts down you'll realize why.
Tobin