I think the first best method is the Subconn Micro, second best is the RMG connectors from Amron that Paul mentioned. Beyond that, I don’t think I’d go with the IP68/69 setup. You can do the complete RMG swap for about $150. I wrote a little something on it at Thingiverse: RMG QD Mold for BlueROV2 Tether Blue Robotics by byke - Thingiverse
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Hi Rusty,
Is there a how-to on your heat-shrink / epoxy splice available somewhere?
I’m looking at extending the length of the cables on our thrusters.
Thank you
Thomas
Nice work… I want to do the same installation.
Note that Christian’s is different from mine and I think his Subconn Micro 8-pin is the best way to go. His Subconn threads directly into the end plate after you tap 7/16-20 threads, whereas the RMG method requires you to pot the RMG cable into a BR red penetrator and it leaves a little pigtail, so it doesn’t look quite as pro. Anyway, I’ll list the links below to what I used…
RMG Locking Sleeves:
For the RMG connectors themselves, you only need a 2-pin, but they were out of stock and they had the 3-pin in stock, so I bought those. Right now, the 2-pin and 3-pin are out of stock, but the female 4-pin is in stock and the male 4-pin is due on Wednesday, so those are the two that I’ll link below:
Scotchcast 2131:
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Why the 3M Scotchcast Flame Retardant ???
In case you come across spongebob and he’s lost his way, tattooed and standing on a corner smoking cigarettes. Don’t really need that RMG connector combusting.
…YEes i really see what you mean Corndog… mine is of stainless steel, and i dont know whats the difference, (that is why im changing, since i have a Boyancy now for 1000m)but i guess its the metal consistence?, right way to do this ! Tnx Cordog, but im not tryineg to ffool anybody in any way… there is a page to con fornt me and say if im doing things Wrong!..and its open for everybody Redirecting... … ;))
I knew you were trying to fool anybody. I just wanted him to be clear that there are differences between yours and mine so that he’s not disappointed when I give him my parts list, but he’s expecting it to look like yours, because the Subconn 8-pin definitely looks better than the RMG connectors. The only reason I went with the RMG connectors is because of convenience. I was able to order them online and they were in stock. The RMG are also cheaper, but it’s not a big price difference.
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i Know that Corndog 
-… just wanted to claify this bec im not into this for the cash… …its Fun
But hey, there’s nothing wrong with a little cash and a little fun! 
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We’ve been terminating tethers for BlueROV2 customers for a while now and have standardized on the Subconn MCOM8F/MCBH8M combo. So far this setup has worked very well. As mentioned above, these rubber molded connectors have been very hard to come by at times, so we have started keeping them in stock to eliminate the associated lead times.
It would be great to see more pics of what other people are doing for tether disconnects.
BlueLink, LLC is an Official Blue Robotics Distributor located in Southern California. www.Blue-Linked.com
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Hi Jeff,
What is the advantage of MCOM over MCIL? Is it harder to connect it to the tether?
Regards,
If molded properly, both will work well for many applications.
In our opinion, it makes for a much cleaner configuration on small UUVs. The “hotdog” mold that the MCIL requires is fairly large and does not look as professional as using an MCOM. Using an Overmold Connector also allows you to terminate directly to the pins of the connector, providing better continuity (not a big factor thought).
One disadvantage to the MCOM is that it typically extends the bend radius of the penetrator/cable combo on a subsea housing. To mold an MCOM onto a tether also requires a mold made to fit that particular Overmold Connector.
If you’re working on a WROV, a MCIL type mold will not take up much critical space and can be much easier to terminate in the field/offshore. Many people use the 2131 Splice kit shown below to attach MCILs to other cables/tethers.
Quick question on this topic.
Why is everyone using male connectors on the ROV side and the female connectors on the tether side? Am I missing something important here?
I am sure others will have more expert advice but here are a few thoughts:
- if powering through the tether (or in general for any powered instrumentation) having male connector at the end of the cable would mean a risk of having live pins
- male pins are more fragile (or rather exposed) than female ones. Since it is easier to replace bulkhead connectors (oring and washer) than inline connectors (mold/splice) it may be preferable to use male pins on the bulkhead side
That said, this is not always the case. For example with Acoustic Doppler Current Profilers (ADCPs), both Teledyne RDI and Rowe Tech use this choice whereas Nortek is the other way round (I shall ask them why they went this way…).
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To add to what Eloi already mentioned it is also standard electrical code, anything getting plugged in to the source of energy has a male end.
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How much do you charge to terminate tethers? Is this something I could send my end plate and tether to you to do? I looked at your website and I did not see this listed as a service you offer, but I love how clean and simple your solution looks. I am a computer science major working on a BlueROV2 from a software research prospective. The idea of performing surgery on my tether scares me! 
How has this held up over the years? How deep have you gone with it?