Help deciding on tech system

[brickrncde1]

I have been tech diving for about a year. Primarily we are going 150-200ft. I am looking to start using a back plate and wing system, yet in looking at the sizes I tend to fall in between groups. Having back plates in my dive shop is not a common piece of equipment for display. How do you decide plate size? Harness size? I am 5-7, 220 lbs, with a 46 inch bare chest. When I dive dry, I will require a L or XL harness, yet the back plate size is what throwing me. Any help would be appreciated.
Thanks
Brick

 

[SanDiegoSidemount]

I would suggest you pick your tech instructor first, then contact them for advice about gear. Most tech instructors will be happy to talk for hours about gear. Then when you start training, you won't have to go out and replace anything that's sub-par or not to the agency's or the instructor's standard.

 

[WhiteSands]

I have been tech diving for about a year. Primarily we are going 150-200ft. I am looking to start using a back plate and wing system, yet in looking at the sizes I tend to fall in between groups. Having back plates in my dive shop is not a common piece of equipment for display. How do you decide plate size? Harness size? I am 5-7, 220 lbs, with a 46 inch bare chest. When I dive dry, I will require a L or XL harness, yet the back plate size is what throwing me. Any help would be appreciated.
Thanks
Brick

I'm no expert, and these tips are from my own experience only.

For backplate sizing, this is what I look for.

1. Top of plate should be just below the large vertebrae of your back. It should be around where your shoulders start to drop down vertically to your arms. You should be able to reach back and touch the top region (and about 5cm more) of the back plate.

2. With the top of the plate at that location, check the bottom of the plate. The bottom edge should not be so long as to dig into your hips or butt. It should end near the small of your back.

3. Look at the slots where the waist strap come out from the backplate. The location of those slots should allow the waist strap to come out horizontally or at a slight downward angle, when the waist strap is on or 1" below your navel. If the straps come out at an upward angle, no matter how slight, the plate is too long. If the downward angle is too big, the plate is probably too short.

4. Position the plate correctly, then get someone to press the plate hard on your back and see if it's comfortable. There should be no hard corners or jutting parts that you can feel on your back. I have tried some brands of plates which were bent at an angle that was too aggressive, which resulted in the side edges of the plates digging into my back.

For harness, just use a continuous piece and you do not have to worry about sizing. It can be made to fit anyone. When switching between sizes, you have to leave some excess webbing, and resize accordingly.

If you want good quality and ease of adjustment straight out of the box, I highly recommend the Halcyon Infinity system.

What kind of BCD are you using now for your tech dives?

 

[brickrncde1]

I was trained using a Seaquest Balance with 120HP and 30 sling with the sling positioned on my L side. It has been a good set up, but I would like the versatility of a tech rig so I can add doubles down the line. I have used my instructors doubles before with with tech rig which was created from multiple systems. I am wanting a rig where I can adjust sizing easy since I dive year round. The winders are dove dry, the summers in 5mm farmer johns, and late summer in just a top. My main objective is to simplify. My instructor dive aqualung rig and my dive buddy dives OMS.

 

[GCullen94]

Ok couple things:
First off go with a simple harness. It is easy to adjust and once the harness is set, it is perfect for your body every time you put it on. There is also less clutter and less to go wrong.

Second. Most agencies will require a drysuit with steel doubles as they are too negative to be balanced in just a wetsuit. You will also get cold hanging on deco as you are not moving at all, therefore a drysuit makes a lot more since as it keeps you warmer, has redundant lift and better for pockets.

Third. BP/W brands are interchangeable... My rig is a Diverite simple harness, Hollis SS plate, Highland bands and a Halcyon wing.

Fourth. Personally I'd look at HOG if you are on a tight budget, DSS, Dive Rite and Halcyon (Least to most expensive) Halcyon and DSS have multiple sized plates.

5th. Keep the amount of lift you need reasonable. There is no reason for a 100lb wing. Ever. 40-60lbs will be more than enough.

 

[PfcAJ]

200ft on a single hp120. Wut?

 

[GCullen94]

Also yeah 200ft on air on a single tank... HUH???????

 

[OtherHalf]

Third. BP/W brands are interchangeable... My rig is a Diverite simple harness, Hollis SS plate, Highland bands and a Halcyon wing.

I would slightly disagree with that. Different manufacturers cut their plates to slightly different shapes so the profile better fits the shape of the wing. I just finished heavily reshaping my dive rite plate to fit my Hollis wing and drilling new bolt holes. It was pinching the bladder because the top of the diverite plate is wider than the hollis plates and was sitting high enough I had to move my wing up to get it to fit with proper trim.
It worked, but wasn't optimal. Personally I didn't mind trimming my plates only because its winter and I had nothing better to do.

Just something to keep in mind when you're searching for gear.

 

[brickrncde1]

Thanks for all the helpful replies. I have a few things to help me consider my options. Yes....I dive 180-200 on single hp120 air with sling of 50% for hang times. Run time is short, yet time below 100 is usually long and total dive time is about 45 minutes finishing without hitting decompression. I finish with over a 1000 psi in my 120s.
Thanks

 

[Teller]

Thanks for all the helpful replies. I have a few things to help me consider my options. Yes....I dive 180-200 on single hp120 air with sling of 50% for hang times. Run time is short, yet time below 100 is usually long and total dive time is about 45 minutes finishing without hitting decompression. I finish with over a 1000 psi in my 120s.
Thanks

It does not matter how much gas you have after the dive. Thats not the point. You dont have the redundacy that you would have if you dove doubles or SM.