D7000 Housings/ Looked at 4 different at BTS
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Viz'art
Contributor
Have to agree with Jean here (dangit!). While I did like my Nexus and it was very very solid, getting the port off was a major PITA sometimes. And the whole issue with having to rotate the dome shade is a downside too.
I much prefer the Nauticam locking system over housings I've owned previously. Locking extension rings, locking port.
Cp
Why did the threaded ports cause the flood?? The threads just hold
the port to the housing, as would a bayonet. It's the O-ring that
keeps the water out.
And for those who have trouble getting the port off:
http://www.sears.com/shc/s/p_10153_12605_00945570000P?prdNo=5&blockNo=5&blockType=G5
Viz'art
Contributor
When you screw a port down, it applies pressure on the O-ring, if this is not perfectly lubed, there is the risk that the O-ring will stretch i some area due to friction, resulting in an uneven seal, a bayonet does not perform the same, its a side seal and ambiant pressure is what presses the O-ring down, also, you so much as rotate a screw port a fraction and you will release the sealing property of the O-ring, a bayonet, if left unlocked, could rotate on itself without having any negative effect on the sealing property of the O-ring.
I am not putting down screw mount ports, after all, this is what we were using in the past, I am just validating our choice for switching to bayonet a couple of decades ago
I agree with what Jean has said.
Screw on ports have a lot of drawbacks. In general, you don't want to slide a surface too far against a compressed o-ring, because of risk of heating the o-ring (if you heat a compressed o-ring through friction, you can permanently deform the o-ring through the Joule effect, lose compression force on the seal, and cause a leak). Localized stretching and twisting of the o-ring, as Jean has mentioned, are other serious issues.
When I designed my own custom housing, I made the port install on straight, with tabs for thumbscrews to hold it in place mechanically. I often have to rotate it a little to get the thumbscrews to line up, but it's less rotation than a screw-on port or even a bayonet port.
Screw on ports have a lot of drawbacks. In general, you don't want to slide a surface too far against a compressed o-ring, because of risk of heating the o-ring (if you heat a compressed o-ring through friction, you can permanently deform the o-ring through the Joule effect, lose compression force on the seal, and cause a leak). Localized stretching and twisting of the o-ring, as Jean has mentioned, are other serious issues.
When I designed my own custom housing, I made the port install on straight, with tabs for thumbscrews to hold it in place mechanically. I often have to rotate it a little to get the thumbscrews to line up, but it's less rotation than a screw-on port or even a bayonet port.
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