Mach V on DSS/Hog Setup

[CrazyMike]

My reg is a Genesis OZ - yoke. The tank valve is the standard yoke (VA200) valve if I'm not mistaken.

I just went and tried taking the top cam strap off and looping it underneath the STA below the original top slots. It lowers the tank about 2 inches (almost exact same position as cam slots in the DSS backplate) and looks like it will probably work. Not as pretty, but I guess I won't notice that when I'm diving. I tried laying down on my bed to simulate a swimming position - the tank still hits the back of my head if I look up but not nearly as badly as before. Won't really know how well I like it until I get it in the water again (hopefully next weekend)...

Yeah, this whole thing is a production of mixing/matching parts from various vendors. Sometimes it works, sometimes it doesn't. I don't think this would be a problem at all (matching Oxycheq wings and DSS backplates), however the design of the Mach V requires a STA, so now the cam band placement becomes a function of the STA and how it bolts up to the backplate - where as traditional setups have their cam bands correctly placed by using the backplate slots. From what I can tell, STA's typically have the cam band slots too far apart as they are centered on or just inside the 11" bolt pattern - this is a documented complaint regardless of the backplate used. Having said that, I'm not sure this wouldn't still be a problem with an Oxycheq backplate as well as other backplates when using a single piece STA.

So, yeah, if you buy the complete DSS setup, you shouldn't have this issue as it will lower the tank about 2" lower than I described in my original post since you can use the cam bands in their intended position on the backplate. For now, I'm gonna try to make what I have work for me without much more purchasing/effort if possible.

 

[JessH]

I really liked this option, but I would have to put a hole in the Mach V as well. This would be the cheapest and potentially easiest solution (as far as a more permanant fix.). I hate to put a hole in the wing, but if I can get it done correctly with a grommet, this might be the way to go and it could save a little weight over the DR STA option.

This is not necessarily true since with a two piece STA you don't have to stick with an 11" spacing. The Mach V has multiple holes for the bottom hole and multiple for the top. At the bottom of the wing I align the top hole with the bottom hole on the backplate. I then drilled a hole so that I can put the top STA bolt through where the bottom hole in the wing is. This lowers the top cam band a few inches and does not require adding an additional hole to the wing. It also positions the wing as low as possible which moves the lift down a little bit which helps with heavy feet problems.

~Jess

 

[Nemrod]

There are three variables your dealing with.

1) is tank position
2) is wing position
3) is plate position

They are not the same and moving each of them does not result in the same--uh==result. You do not want to lower the wing way down on the plate. The plate can be dropped somewhat by lengthening the shoulder straps and shortening the crotch strap so that the plate rests more naturaly centered in the back. Not only do people wear their tanks to high but also their plates are worn to high.You do not want to lower the wing beyond a normal range because it can effect trim. Be aware of that.

I suggest that you lower the plate as I suggested with the straps and crotch strap and that you CENTER the wing on the plate. I suggest that you lower the upper camband and thereby allowing you to LOWER the tank.

OK, argue with me if you like but long before there was DIR, GUE or any gurus there was the New Science of Skin and Scuba. It is pictured there and in many older texts the CORRECT position of tanks. A single tank does not require the manipulation of multiple valves and therefore sitting it correctly should be the goal. The correct position has been known for decades and it is----the valve should be centered between the shoulder blades. Obviously, physical variastions of the human body, various tanks etc may alter that BEST position slightly but the current fad of wearing single tanks and backpacks up behind the neck serves no real purpose.

Think about what your doing and why your doing it before you do it.


This is not a very good picture but here you can see that my tank, valve or regulator are NOT banging my head. The plate is the Freedom Plate II which tends to correctly position itself thanks to ergonomic design. No, there is no wing on it in this pic but the pic does show--wing or not---my tank/reg is not whacking me in the head. My trim is neutral and my bouyancy is neutral (as best it can in 1/4 inch of vintage highly compressible neoprene--lol)

Here is a ic from the New Science, you do not need to wear a single hose rig quite this low but the picture will get you into the ballpark.

N

 

[cool_hardware52]

There are three variables your dealing with.

1) is tank position
2) is wing position
3) is plate position

They are not the same and moving each of them does not result in the same--uh==result. You do not want to lower the wing way down on the plate. The plate can be dropped somewhat by lengthening the shoulder straps and shortening the crotch strap so that the plate rests more naturaly centered in the back. Not only do people wear their tanks to high but also their plates are worn to high.You do not want to lower the wing beyond a normal range because it can effect trim. Be aware of that.

I suggest that you lower the plate as I suggested with the straps and crotch strap and that you CENTER the wing on the plate. I suggest that you lower the upper camband and thereby allowing you to LOWER the tank.

OK, argue with me if you like but long before there was DIR, GUE or any gurus there was the New Science of Skin and Scuba. It is pictured there and in many older texts the CORRECT position of tanks. A single tank does not require the manipulation of multiple valves and therefore sitting it correctly should be the goal. The correct position has been known for decades and it is----the valve should be centered between the shoulder blades. Obviously, physical variastions of the human body, various tanks etc may alter that BEST position slightly but the current fad of wearing single tanks and backpacks up behind the neck serves no real purpose.

Think about what your doing and why your doing it before you do it.


This is not a very good picture but here you can see that my tank, valve or regulator are NOT banging my head. The plate is the Freedom Plate II which tends to correctly position itself thanks to ergonomic design. No, there is no wing on it in this pic but the pic does show--wing or not---my tank/reg is not whacking me in the head. My trim is neutral and my bouyancy is neutral (as best it can in 1/4 inch of vintage highly compressible neoprene--lol)

Here is a ic from the New Science, you do not need to wear a single hose rig quite this low but the picture will get you into the ballpark.

N

A couple points.

In the photo of you wearing your fredom plate it appears the top edge of the plate is at least as high, perhaps higher, on your back as any plate I might make or use, ie. at about the base of your neck.

Your vintage picture shows a double hose reg on a period bottle. These early valves, as I sure you know, had small "winged" nobs on the top of the valve, not the side as do current valves. Even with tanks mounted quite low, a reasonably flexible person could reach the top mounted valve handles.

I know I used to be able to when diving a Scuba Pro blow moled backpack, which incidentally is shaped like and fits much like your current plate.

I like being able to reach my valves, singles or doubles. A yoke valve and double hose reg of course precludes having the regulator behind your head.

Modern din valves and small first stages require much less room.

Vintage gear is great, but progress permits new techniques.

Tobin

 

[CrazyMike]

This is not necessarily true since with a two piece STA you don't have to stick with an 11" spacing. The Mach V has multiple holes for the bottom hole and multiple for the top. At the bottom of the wing I align the top hole with the bottom hole on the backplate. I then drilled a hole so that I can put the top STA bolt through where the bottom hole in the wing is. This lowers the top cam band a few inches and does not require adding an additional hole to the wing. It also positions the wing as low as possible which moves the lift down a little bit which helps with heavy feet problems.

~Jess

Ya know, you're absolutely correct, I hadn't thought of that. I went and measured, the hole spacing on the Mach V is about 1.5". Doesn't get it way down, but it helps. I can probably simulate that with the top cam strap under the lightweight STA and pushing the tank up 1/2" and see if I can stand it there. Thanks for setting me straight!

 

[halocline]

There is a simple, easy solution; turn the tank around so the reg is on the other side of the tank neck. If the tank is really close to your head, this will probably improve your routing as the slight increase in distance makes the hoses follow a slightly tighter curve. If your reg is a typical right angle barrel, you're going to need to either point the reg barrel down or change the hp hose to the other port (probably there are two) so that it will rout to the left. So the tank valve is on the left, big deal. You can still reach it.

If you set up your reg like this, you'll see that it's actually less of an entanglement hazard; the yoke knob is now pointing in, and the hoses will help to keep stuff like monofilament from getting caught in the reg/tank valve.

 

[Nemrod]

Again, I like to avoid negative comments about products I never used, I like the DSS products, may soon buy a plate from you. I dont dissagree about the top edge of the Freedom Plate either. As to the valves, all of my valves, new and old are side valves as is modern practice. BTW, I dive both modern and vintage gear and I am fully cognizant of the requirments of both. I agree, you need to reach your valves but with a single the the "valves" is --singular not plural---therefore a simple pressure check, watch SPG, inhale, needle does not drop--air is on--no big deal. Besides, I can reach the valve in the configuration.

BTW, I am diving a Hammerhead, Halycon and a Freedom Plate as well as vintage rigs.

Quote:
"Vintage gear is great, but progress permits new techniques."


This is not a vintage argument, I specifically stated he might not need the tank as low as in the picture but I might remind you and all, I am not the one with the tank hitting me in the head--vintage or modern or otherwise. You guys are.

I will also say that if your wearing a drysuit or other heavy exposure protection with your doubles rig then it certainly makes sense to keep the tank valveS up high were they can be reached more easily. Nothing about the OP made me think he was drysuit diving with doubles, if so, nevermind. Nonetheless with a single rig, having the double slot upper camband allows one to select the tank--high or low--without altering the basic setup--it is a flexible alternative solution to head banging.

N

 

[diver 85]

Why? The OP has built a "Frankenstein" You and I discussed using all DSS gear, i.e. a DSS plate with a DSS wing. There is no need for a STA with our gear. It is the STA that creates the problem. The camband slots in both our wing and Plate are much closer together than they are on most STA's That allows a much greater range of tank positions.

Tobin

Like I stated earlier, I'm not used to the lingo used in these systems ie STA's etc........Was hoping none of his problem would come into play in your system......sounds good........Email me tomorrow @ drjr52@yahoo.com when you get a chance on the TTW picture you have.......thanks...........

.......Joe ...........

 

[airsix]

Tobin is just a little miffed that one of his kids married an Oxycheq.

Me? I was hopping this union would finally bring the feuding families to a truce. :shakehead

-Ben M.

 

[cool_hardware52]

Again, I like to avoid negative comments about products I never used, I like the DSS products, may soon buy a plate from you. I dont dissagree about the top edge of the Freedom Plate either. As to the valves, all of my valves, new and old are side valves as is modern practice.

That may be so, but the picture you posted as an example of "proper" tank mounting was clearly a "top actuated" valve.

Nonetheless with a single rig, having the double slot upper camband allows one to select the tank--high or low--without altering the basic setup--it is a flexible alternative solution to head banging.

Or just use a plate and wing without a STA. The camband slots in all the plates I know of permit a wide range of tank positions.

Tobin