Mach V and Hammerhead BP

[bluewatertoy]

My wife and I are both diving the exact same rig. I am 5'10' she is 5'6" and neither one of us has the 1st. stage hitting the backof our heads. I am using an Oceanic 1st stage and she is using an Aqualung. We both like the tank high on our backs and have no problems at all. The Oxy Mach V is one beautiful wing.
Kelly

 

[halocline]

Not sure who the "jetharness" fellow is you're referring to, but several months ago I started a thread about my Mk15 (a tall reg) hitting my head despite adjustments on my jetharness plate. My solution was to first cut a strip of boat decking rubber and slip it underneath the cam straps; it lifts the tank about .5" off the plate, and provides a nice solid semi-compressable surface for the tank to sit on. Then I just turned the tank around so the barrel of my reg is on the other side of the tank neck. This does have the advantage of making some of the "gear police" on dive boats nervous, because my tank valve is on the left rather than right...

It actually improved the hose routing in my case because the reg is in so close on the flat jet plate that having the reg a couple of inches back allows the hoses to rout a little tighter in, rather than bulging out a bit. It also appears to be less of an entanglement risk, although this seems counterintuitve. The yoke knob is now pointing in towards my head rather than sticking out, and while the reg barrel is further away, remember that there are hoses coming out of the barrel very close to the top; these (I would guess, never having had the misfortune to find out in practice) should tend to keep stuff like monofilament from getting caught on the reg barrel or top of the tank valve.

I would suggest to anyone who can't find a different way to keep the reg off their head to at least try turning the tank around. You can still reach the valve, you just do it with your left hand.

 

[Nemrod]

http://www.jetharness.com/page_templates/index.cfm?page_id=38

The link above should take you to the web page describing this sytem and it's reasons for being different. That would be the Jet Harness fellow I would be speaking of. Reading it some time back it seemed to make sense given my observations of backplates and their problems in general. I am not endorsing it, I just thought the concept was different enough to merit discussing. Not discussing it any further, just clarifying the link to the page you asked about to eliminate your confusion. Below is another interesting link some might find useful.

http://www.gasdiving.co.uk/pages/misc/kit/singles.htm

This ebay link, not mine, takes you to an old dog bone style plate. With a little imagination, I think one might see how that concept could be updated. It is much like the Jet Harness Plate and the Mark Meadows low profile plate. BTW, this plate is from around 1962.

http://cgi.ebay.com/US-Diver-Aqua-l...4QQihZ012QQcategoryZ74003QQrdZ1QQcmdZViewItem

Adios.
N

 

[halcyon]

Hey guys,

Thanks for all your replies. Will try loosening the straps and lowering the plate, and all the other useful tips to see what works.

FYI I'm using an Apeks xtx FSR 1st stage and with the logo/diapgragm side pointing up it does add almost an inch of height. Will reverse it and that shd help slightly.

Thanks also for all the pics, Nemrod and Floater - that really makes things easier and a lot more colourful. This board is never boring. Cheers!

Halc

 

[Patrick]

Again, show me, the STA is not the culprit, the entire doubles optimized design with that high central ridge is the problem--for a single.
N

Nemrod,

You are correct. Plates were originally designed for doubles. The first plate was made out of a street sign by Greg Flanigan.

STAs were made for those who normally dive doubles, but needed the STA when doing single tank diving. There are some advantages for diving a normal sized plate --- less lead on weight belt, ability to move up to doubles without the investment in another plate, additional attachment points, etc.

IMO, one of the best plates for single tank diving is the old plastic plate. It has a handle, is very light and compact for travel, and they are dirt cheap (not water front dirt). A number of people have used them with our wings already. Also, a crotch strap is not needed with the plastic plate because you can tighten the system quite well. That said, some people will find it difficult to believe because they have been sold on the need for a heavy stanless plate. If you used one of the older plastic plates and wanted to add weight to it, you could add lead bullet weights on both sides of the cam straps. This method can also be used with existing steel plates.

In the end, the customer is going to buy what they want and feel they need.

Best regards,

Patrick
---
OxyCheq
http://oxycheq.com

 

[Patrick]

Hey guys,

Thanks for all your replies. Will try loosening the straps and lowering the plate, and all the other useful tips to see what works.

FYI I'm using an Apeks xtx FSR 1st stage and with the logo/diapgragm side pointing up it does add almost an inch of height. Will reverse it and that shd help slightly.

Thanks also for all the pics, Nemrod and Floater - that really makes things easier and a lot more colourful. This board is never boring. Cheers!

Halc

Halc,

Glad to see others offered the same correct solution --- lower the plate.

Depending on your height and the lenght of the plate, you may only be able to lower it so much.

Two months until OxyCheq moves to Marianna FL. 3 minutes from Mill Pond (5 cave systems) --- oh, I am really going to hate that. That three minute drive is going to be tough to handle.

Best regards,

Patrick
---
OxyCheq
http://oxycheq.com

 

[JessH]

Am using the Hammerhead 2 pc light STA which is quite thick and can only fit to the 2nd highest grommet on the wing - am wondering if a slimmer STA might be able to fit to the 1st (highest grommet) and thus allow a lower tank position.

I assumed the same thing, then once I tried it I realized that the STA actually fits in the top hole just fine. The wing simply conforms around it. I don't think this will actually help you though since I don't see how moving the STA higher would allow you to move the tank lower...

I have the same setup as you. I currently have my tank riding very high because that is the only way I have been able to achieve good trim. I recently purchased a lighter STA and am plannign on trying that with some lead on the top cam band to hopefully be able to move the tank down a bit without negatively impacting my trim.

~Jess

 

[stefusa]

That is actually the rig I am preparing....
I am waiting for my backplate and STA very soon, and I just order the machV 40 from scubatoys this morning...
Hopefully I will not to have to wait 10 days...
Mister U_S, RUN !

 

[halcyon]

Halc,

Glad to see others offered the same correct solution --- lower the plate.

Depending on your height and the lenght of the plate, you may only be able to lower it so much.

Two months until OxyCheq moves to Marianna FL. 3 minutes from Mill Pond (5 cave systems) --- oh, I am really going to hate that. That three minute drive is going to be tough to handle.

Best regards,

Patrick
---
OxyCheq
http://oxycheq.com

Hey Patrick,

Yup, thanks for pointing that out handily!

Shd be able to lower the plate easy cos I'm 5'11 and the plate's a medium.

3 mins away? Awww.. poor u. FYI I am 2hrs away from the nearest decent dive spot here but can't dive now cos of the regional monsoon. Hope to be taking your outstanding Mach V to Indonesia instead in December and see if I can use it to sneak up on other marine life there.

Great wing!

Halcyon (oh, the irony!)

 

[halcyon]

I don't think this will actually help you though since I don't see how moving the STA higher would allow you to move the tank lower...

Yup, I've just had that pointed out to me! *blush*

Amazed you could fit the HH STA at the top grommet tho - looks like an impossible squeeze!

Thanks, Halc