Thinking of doubling up my HP80s

[Marie13]

It’s a good thing the bolts are long as I can still get BP on even with Cinch system.

Got them into my apartment, into my comfy chair in living room, put them on (without regs), and walked around my apartment with them on. Heavy, but doable. My knees are not unhappy. Good thing I’ve been working out so much.

Here it is all assembled. Just missing wing inflator hose. Length I need is on order. Perdix transmitter will go on right post.

 

[Marie13]

Ended up getting hoses specifically for doubles rather than cannibalizing my single tank setup.

 

[guruboy]

For a cinch you want the bottom bolt to be a little longer but the top bolt should be the same length still.

But as long as they aren’t too long, I guess it’s fine.

 

[Compressor]

@Marie13 I played with my bolts multiple times. Multiple trips to Home Depot and Lowes to figure it out. I wanted the bolt to come out without really digging into my spine. I wanted to bolts to come out and be as flush as possible with the nuts I use to secure them. A little OCD on my part I admit. I know the plate is curved. Instead of wing nuts, I bought these Delrin thumbwheels from DGEx and I love them very much. For me one ended up being 3.5" and other 4" bolt. I ended with stainless steel carriage bolts as I could not find stainless steel bolts that are fully threaded.

The HP80s get a bad rap as not having enough volume. Glad its working. They look good.

 

[Marie13]

@Marie13 I played with my bolts multiple times. Multiple trips to Home Depot and Lowes to figure it out. I wanted the bolt to come out without really digging into my spine. I know the plate is curved. Instead of wing nuts, I bought these Delrin thumbwheels from DGEx and I love them very much. For me one ended up being 3.5" and other 4" bolt. I ended with stainless steel carriage bolts as I could not find stainless steel bolts that are fully threaded.

The HP80s get a bad rap as not having enough volume. Glad its working. They look good.

Since I have the backpad on my BP, I’m not worried about them digging me in the back. The bands are old - from the 80s. The bolts that came with them were old and shot, so the shop used new bolts. They have bolt kits.

Once the doubles were bolted to BP, there really isn’t a lot of length sticking out.

I have the Delrin thumb wheels already for single tank set up. Just have to get ones to work with this bolt diameter.

Figured out total weight must be somewhere around 80lbs. Each tank is 28lbs empty. I read somewhere a full tank adds 6lbs for an AL80, so that’s close enough for mine.

 

[hammet]

Hi marie,

Interesting thread. What is your typical dive profile?

 

[Marie13]

Hi marie,

Interesting thread. What is your typical dive profile?

Dwarf dubs are in advance of tech in a couple of years.

I’m doing 2 tank charters. Rec depths. I’ll get 2 rec dives out of these. I’ll still be doing a lot of single tank stuff as well. Will practice with these all season and hope to maybe do Intro to Tech later in the season.

 

[rhwestfall]

@hammet : many of us use doubles on recreational trips. Saves switching, and maintains skills on the same platform...

 

[RyanT]

@hammet : many of us use doubles on recreational trips. Saves switching, and maintains skills on the same platform...

+1

 

[rjack321]

I ended with stainless steel carriage bolts as I could not find stainless steel bolts that are fully threaded.

That's because the threads have to be custom cut which is a huge pain in the rear for stainless.