So, like many others when we received our OpenROV and assembled it water submergence testing showed a major amount of water leaking into the electronics can, I've said in other parts of the forum, but I am a Mechanical Engineering Student currently on a Work Term. Part of my work term has been helping some people here are the university in geography assemble their newly purchased OpenROV. Due to the fact that they don't have access to a shop, and by handing the ROV over to them when its completed I don't want there to be any chance of leakage I was wary of the Teflon tape / Latex balloon / Rubber bands solution. Initially tried Teflon and needed upwards of 5 layers on each side and still did not get a perfect seal.
I am also a member of our local International Competition level ROV Team, so I was familiar with endcap design, and O-Ring Design, and the shop I'm in had some spare 10 Pin Subconn connectors laying around (http://www.subconn.com/connectors/micro-series) to replace the epoxy potting.
Therefore, to solve the waterproofing issue I designed new endcaps in Solidworks to be manufactured out of HDPE. They allow for two 10 pin Subconn connectors ( one of the AUX wires is now just inside of the electronics can) which seal against the HDPE face with their own O-Rings. on the other end of the can I replaced the syringe with a swagelock fitting that simply seals with a M5 bolt, and when released releases the vacuum.
They were manufactured at our campus Technical services for about 60$ for the set, including one set of 1/8in O-Rings which were made in the shop out of 1/8 O-Ring Stock. We also got 4 spare rings made. they did them on a computer controlled lathe out of one solid piece of HDPE.
Some modifications were made to the chassis to accept the connectors
( just a couple of holes), nothing major!
They have been water tested for over 15 hours of submergence with no leakage whatsoever, but I haven't been able to test it with the ROV going yet, as we are still waiting for our batteries to arrive!
All in all, we are really pleased with them. It was also lucky to have the extra subconn connectors lying around. If we were to purchase the whole set ( two bulkheads and two connectors) it would have cost several hundred Dollars.
I have attached some pictures, as well as the solidworks files. If anyone wants a specific format let me know!
1037-IMG_0493.JPG (381 KB) 1038-picturesOfNewEndcaps.zip (1.21 MB) 1039-SolidworksFilesNewEndcaps.zip (435 KB)