Fathom w/o a stand

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inquis

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I'm having issues with bumping the O2 reg/valve on a Fathom Mk3 with LP50s when on land. When tipped back, the reg/valve makes contact with the bench which obviously isn't good. I've taken to adding/removing the O2 bottle (and attaching/removing the O2 regulator) while absolutely vertical (or tipped forward), but I feel it's just a matter of time until it slips a little (while getting in/out of the harness), tips back too much, and something breaks. A sidemounted BO configuration would work for some of my sites, but I'd like to have a "boat rig", well... when I'm on a boat. :) Am I missing something, or has anyone else noticed this issue? Short of switching to AL40s (which do just clear without contact, brackets are in the same place) or finding a stand, any tips?
 
I'm having issues with bumping the O2 reg/valve on a Fathom Mk3 with LP50s when on land. When tipped back, the reg/valve makes contact with the bench which obviously isn't good. I've taken to adding/removing the O2 bottle (and attaching/removing the O2 regulator) while absolutely vertical (or tipped forward), but I feel it's just a matter of time until it slips a little (while getting in/out of the harness), tips back too much, and something breaks. A sidemounted BO configuration would work for some of my sites, but I'd like to have a "boat rig", well... when I'm on a boat. :) Am I missing something, or has anyone else noticed this issue? Short of switching to AL40s (which do just clear without contact, brackets are in the same place) or finding a stand, any tips?

Get valves with the bumpers.
I’ve had our fathoms 4+ years. You do have to be careful loading in and out of the car you don’t turn on the oxygen. Neither of us have had an issue while the units are standing leaning on a dive bench. But there is the potential for it, so we always check pre-jump.
As ratsbud said are you using inline valves with the bumpers?
 
I'll go set it up and take a pic tonight, but this one of @kierentec is pretty close to what I have.
1702403799468.png
 
Looking at the above picture, I may be able to shift the 50s down some. There, it looks like the top of the canister is a hair above the tank shoulder. I'm trying to keep the height of the valves above the backplate attachment bolt around the standard doubles height (~7"), but I do have a little room to shift that central bracket down to maintain that distance. Effectively, shift only the can & O2 bottle upward relative to the backplate. It would give me a bit more lean before it becomes an issue.

Actually, if anyone has measurements of their bracket heights relative to the top (or bottom) of the canister, that would be a good sanity check. Currently, my central/BP bracket and the 50s brackets are all 1" from the top, with the valve handles 6" above the top of the central bracket (so 5" above the top of the can).
 
@rddvet , no I'm not unfortunately but I have considered it. I have bumped the o2 on by accident more than a couple times it's just part of a check I do during transport now especially since I run a button /no spg on there.

I see a couple different styles valves with bumpers. If you have the threaded inserts just stick a bolt with a bushing on there to space it a hair.
20231205_062245.jpg
 
The regs and valves can take it. The biggest annoyance I had in that configuration would be the O2/suit inflation valves rolling on when I slid the unit into my car. With 1st stages attached it would lead to me watching the CL's fill up in my rear view mirror as the needle valve was constantly adding oxygen. Added a mental checklist item to double check all valves are closed when inside the car and stopped having the issue. With no 1st stages attached the roll on was quite annoying so I bought a set of the Din plugs with integrated pressure release for transportation.
 
I mount the 50s as low as possible while still being able to reach the valves. I keep the top of the shoulder of the tank just about in line with the top of the canister. This helps a lot with trim/balance as well as leaving more room under the can for the O2 reg/valve. I’ll dig around a bit for a better pic and post it when I find something.
 
Sorry, best I have at the moment, but I think you can get a pretty good idea on where it all sits.
 

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