Halcyon Backplate and Harness

[stephenws]

Hello,

I've been diving a Halcyon backplate and harness rig for many years now and am wondering if there is much difference between what I have and backplate/harness rigs made specifically for double-hose diving? Will I be able to achieve optimum double-hose tank positioning with what I already have?

Pardon my newbie questions, as a may have several while I wait to get my Argonaut Kraken - hopefully later this year.

Thanks,
Steve

[Herman]

Welcome to the board and DH diving.
Off hand I am not familiar with the Halcyon plates so I am swaging it some but here goes. Looking at the Halcyon plate photos it appears to have a substantial ridge along the spine. If I am looking at the BP correctly, that ridge is going to lift the tank up off your back by an inch or more, that will hurt any DH regs performance a good bit. The next issue is a DH reg should be worn a good bit lower on the back than most people dive single hose regs. The "cans" (metal or plastic main body of the reg) needs to be roughly between your shoulder blades. In my experience, this positioning is difficult to achieve with most modern BCs or plates. The plates want to come to rest much higher than is acceptable even if the straps are adjusted so the top of the plate is in the correct position. If you manage to get the plate low enough, that tends to put the waist strap much too low. When "modern" DH diving, I use a Zeagle ET which is soft BP. In it's factory design, I could get the plate low enough but when I did, my waist strap ended up below my crotch....that did not work and was down right uncomfortable with a crotch strap...which you should use to prevent a BP from riding up. I had it modified to move the waist strap up several inches which put the waist strap where is should be and it now works great..

Then next issue you may have is the top of the plate making contact with the reg cans. That is not good on the cans if for no other reason than it scratches them. Most hard BPs just do not allow the cans to set low enough without hitting them. If you look at Bryans BP, it has the top of the plate cut out to make room for the cans.

So what do you need to look for. First off, find a BP that will keep the tank as close as possible to your back. Any ridge that holds the tank away from your back is not desirable. Some older BP do have ridges along the sides that the tank nest into, that is not a problem, they do not raise the tank but do tend to kept it in line. Tanks stays are a big no no unless they just guide the tank without lifting it off your back. Next make sure the straps can be adjusted so that the BP is low enough that when a tank and reg are mounted in it and placed on your back, the cans set between your shoulder blades AND when adjusted that way, the waist strap is not too low. By the way, your tank WILL feel way to low when walking.
The bottom line is , you can use your current BP but you will suffer a considerable loss of performance in any DH reg. The reg will work and provide you gas but it will not perform anywhere near optimally. If you wish to dive your Kraken as a modern reg, my best suggestion is to get one of Bryans BP’s , they are especially made to work with DH regs and will work fine with any single hose reg as well. If you prefer a more traditional route then look into one of the thin BP’s from the DH era like the Voit Snugpack, the USD Kam-EZ or one of Allan’s harnesses.

If you do a search on the board, you will find a lot of info on diving with DH regs and the BPs to use with them that myself and others have posted over the years. Ask away with your questions, I suspect there will be a lot of folks wondering the same things as the Kraken begins to show up at dive sites.

[21]

I am not familiar with a "Halcyon Back plate and Harness"

I would suggest that you visit E bay and purchase "The science of Skin and SCUBA" or one of the many later editions of "The New Science of Skin and Scuba." Or send me $5.00 and I will mail you a copy that covers double hose regulator diving.

Spend the cold snowy winter in your local pool mastering ALL the exercises in the book then head to the closest mud puddle and slowly acquaint your self with the double hose bubble machine.

There is a huge difference in a single hose and a double hose regulator.

Then plan on a vacation to Ohio for the annual gathering of the tribe at Portage quarry in August-- You will lean much from the many double hose veterans in this group.

SDM

[swimjim]

Herman's advice is spot on. With a double hose reg positioning of the cans is critical to the performance of the regulator. Here's a picture of me wearing a VDH back plate, 38 lb wing and a prototype Kraken mounted. By the way, the strap on my arm is from my weight harness, which is a work in progress. Ha




You'll notice that the cans ride between my shoulder blades. In this case the reg is actually a tiny bit low, but pretty close. You will also notice that the cans are touching my back. This is about as good as it gets for a double hose.
In my modern diving, I used to use a Seaquest Pro QD BC and for the last 5 years or so I've been diving an Apex backplate. With both of these the regulator tends to sit a little away from the body and usually up behind the neck. While this is fine for a single hose, it really hampers the performance of any double hose. Good luck!

Jim

[luis]

The Argonaut Kraken case is specifically designed to work with many more backpacks and backplates than most other double hose regulators.
The tapered shape of the front can is intended to reduce the chances for interference and the back can has a large cutout/ chamfer to provide more volume for a variety of different BC bladders/ wings.

As mentioned above, not all BC or plates will work as well and that is why I designed a new backplate (based on elements from a vintage 1950’s backplate design) that would locate any double hose regulator in the preferred spot. The VDH backplate was also designed to accommodate many commercially available bladders and it is designed to use a conventional style harness.

The VDH backplate is also designed with the shoulder straps crossed to provide much better control of the tank position (and keep the straps from falling from the shoulders). The shoulder strap attachment on this backplate is almost at the same level as the tank valve (as opposed to a vintage harness that attaches down below the tank shoulder). The harness attachment on the VDH plate limits the side to side motion of the tank so that the regulator stays at the ideal location.

The Argonaut will have a lot less interference with many backpacks and backplates, but (as Herman mentioned) you still don’t want a back plate or backpack that separate the tank away from your back.

If you already own a backplate and wing, you can probably transfer the wing and harness to the VDH backplate. The VDH backplate is very simple and its cost is much more reasonable than most other commercially available plates.

[stephenws]

Thanks, everyone, for the input and advice. Sounds like I need to invest in the VDH backplate. Glad to hear I should be able to use my Halcyon wing, as they are quite expensive.

Again thanks. Much appreciated.

- Steve

[Superlite]

Just a curious question. But I'm wondering if a Scubapro Knight Hawk BC (BIU) could be used in conjunction with a VDH back plate.