I nor anyone else at this time understands the leaking housing and can only offer consoling thoughts to the OP however these are some things I know can cause leaks and have caused leaks on other housings I have seen in use or have owned. The tray is often a culprit. When I saw the design of the little, tiny, bitsy, FIX (Recsea) housing I knew I wanted one but I also knew it would require a tray/handle solution that I did not see a commercial off the shelf design I was happy with. I did use an Ikelite for a bit with a custom spacer and it was fine and plenty stiff and did not interfere with the door but it was not perfect with my dual strobes so I went shopping yet again and ultimately made my own.
Anti-flex doubler/adapter designed to isolate the housing from the tray and reduce the possibility of flexing the housing even with heavy lenses and strobes:
Anti-flex doubler/adapter on housing:
Camera and dual handle DIY tray assembled:
Door MUST clear the tray!!!!!!, if the tray can flex and push on the door, well, watch out!:
Another shot of door clear of tray:
Not being an O-ring and camera housing engineer I would prefer to see double spring latches and a thicker or dual O ring even if the resulting housing was a bit larger. I would also like to see a stiffer, thicker bottom. This is not unique to the FIX and RecSea housings but an issue with many aluminum and plastic housings. I had an Ikelite that creaked so loudly at depth it was scary and it was possible to off seat the door O ring at shallow depths and flood the camera by flexing the housing, I learned not to do that. However, I must say, Ikelite housings are generally very robust. Now there is this new Olympus XZ-1 and it's OEM housing with a single attach point, OK, now mount a heavy Inon lens on that sucker and I predict a flex-flier, JMO, could be wrong.
This allows me to mount all of this heavy stuff and even more and then pull, twist, tug, drop, bang and yank on the handles without any flex being imparted to the camera housing base:
While the OP figures through his disappointing circumstance I thought to take an opportunity and show what I mean.
BTW, the blue and gray grips that everybody is using on these trays are Serfas brand MTB grips or similar.
Why are the knobs so big on my tray, because I have arthritis and I need the big knobs when I get cold and it was what I had on the shelf when I made the darn thing.
I know the Canon OEM housings have had seeping/leaking issues with mold flash as I had one myself and had to polish the sealing surface, however, I suspect some of the mystery leaks on the Canon housings are also the housings being flexed in use and allowing the O ring to partially unseat.
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