I had a short week with the holiday. This meant I wasn’t gonna start any big projects this week but I do have some to finish up in the next two weeks before my internship ends. This week I spent a lot of time cleaning and organizing the electrical shop. It hasn’t been organized in a long time and when everything was moved off the ship stuff was kinda just shoved into places. I’ve been working to get everything organized before the winter holidays because when everyone comes back in January it’s gonna be crunch time. It’s really funny (in a not funny way) how messy some of the drawers can be and you can pull out something that hasn’t been used on the sub in some 20 years. Yet some things are older than I am and still heavily used.
Category: MATE Blog Archive Page 32 of 89
Posts that were imported from the historical MATE blog at marinetech.org
I installed another chassis this week. This one took a little more effort since I had to make a new ground wire for it. Similar to houses having ground wires (wires that literally are connected to the ground, buried deep) many parts of the sub are grounded to the surrounding environment (seawater). This is important to protect the electronics in case of circuit overload.
I also set up and installed the new video hub for inside the sphere. The video hub takes all of the camera inputs, and directs their output to various pilot or observer monitors. It can be a simple one input to one output, or one input can output to multiple screens. The difference with the new one is that the connections can be changed from the hub itself as well as from the computer. I was able to boot up the old hub, save the settings, connect the new hub, find out the settings can’t be transferred between two different models, type in the settings, type in the settings again because the hub went through a firmware update and didn’t save the settings, and install the hub into the mock sphere. It’s pretty tight with the spacing up at the top but hopefully there won’t be too much wire switching in the sphere.
New video hub!
Since some of the pressure housings have been pressure tested, I’ve been working on reinstalling the chassises that hold all the electronics. It’s better to pressure test the housings without the electronics just in case there is a leak but this means I have to wait for the pressure tests to finish before I can work on the chassises. This kinda bottlenecks my workflow, but this week I was able to reinstall 2 chassises. I took them apart 3 months ago but I still remember how the process went. It’s actually easier to put everything back together; when I took them apart, the wires did not want to come out of the chassis, but threading them back in is going smoothly. One thing I don’t like dealing with is thermal paste. When the electronics are running, they generate a lot of heat. To deal with this, there are heat pipes running through the chassis that connect to cool plugs outside the housing. This helps conduct heat away from the electronics where it can dissipate in the cold sea water. However, the heat pipes need to be coated in thermal paste to help with this process. Thermal paste is a thick sticky goo that is very difficult to wash off once it’s one. Yet it manages to get everywhere. Working on the wires and end caps around the thermal paste means my arms are covered in it.
The chassis mounted on the end cap. In the front are the wires that are connected to the end cap. They are threaded in the center of the chassis and connect in the middle of the right half of the chassis.
Caught in a moment of victory! A screw had fallen into the chassis and I had to fish it out. Anything dropped in must be recovered in order to prevent any shorts.
More end cap assembly this week. It started with taking locking collars off the old connectors so they could be put on the new connectors. It’s a bit of work to pull out a metal retaining ring that’s resting in a groove inside the plastic collar with the connector leaving very little room. Though taking the locking collars off is way easier than putting them on; trying to shove the metal ring back into its groove in a space too small for my finger to fit is a great way to make your finger sore. It’s like when you’re just learning how to play a stringed instrument and you haven’t built up any calluses yet. Except instead of strings they’re metal rings. I’ve now finished assembling most of the end caps. In order to finish the rest, I’m waiting on the 66 pin penetrators to be soldered. Once they are ready to be installed, then the rest of the end caps will be assembled and the housings can be put together and sent off for pressure testing.
A connector with a red locking collar. That little slice of silver is the retaining ring that needs to be taken out in order to remove the locking collar.
We made it back to Miami on Sunday afternoon. We tied up the ship and helped the scientists unload equipment. Then we cleaned up the deck and
We have been looking into installing exhaust fans for the engine rooms. Most ships have good exhaust fans in the engine room to keep good air flow and pump the bad air out. Our engine rooms have supply fans but not exhaust fans. So our air flow is not that great. So we looked into installing fans. We ordered two large fans. We are looking to install them on the top of our exhaust stacks. The top of the stakes have large vents on their aft sides so we decided it was the perfect place to mount the fans. We unbolted the vent cover on the starboard side to access the top of the stack to get all our measurements. We also looked at our braker panel to figure out how we were going to wire the fan in. We found an open breaker to wire the fan and I calculated the wire gage we would need for it. We then bolted on some spacers to the frame of the fan so it would fit perfectly with minimal movement when we had it mounted in. We attached the weirs to the fan before we lifted it into place. We then had to hoist it up into place and bolt it in. Once it was in we wired it to the ship’s power with a switch. We could then put the vent cover back into place. The fan worked great. Now we will just have to do the starboard fan once we have some more time.
This is the fan in place!
This week has been full of reassembling the pressure housings. It’s been a little stop and go because we need some parts to work on one thing so that’s delayed, then this one needs to be tested first so bump that up, this part isn’t finished yet so push that back. Some of the waiting was so I could get work instructions on how to assemble the pieces. Specifically with the vacuum ports that were just added. Adding a vacuum port allows the pressure housing to be sealed without air trying to push the end caps off. In the one housing that was assembled this week, it was a bit of an experiment working with the vacuum port. Trying to get it assembled and see how long the pump takes to draw the air down. So we stood around and watched the pump go. Thrilling times.
The pressure housings have all been returned and I was able to verify them all! Everything went very well; only one piece will need to be sent back to be readjusted. For each adjustment that the machine shop made, I had to verify. This means that I had the part drawings and a set of calipers and I measured the parts to ensure they were within the tolerance. With the through holes, I was able to fit check by test installing the pieces, whether it be a vacuum port or a fiber optic connector.
I’ve also been continuing to work on the wire inventory. It’s amazing how many pieces of wire there can be on one box. And there are several boxes. At this point I’m about halfway done and hopefully will be finished up early next week.
The pressure housings have been moving back and forth between the lab and the machine shop again this week so I’ve gotten more of a workout. Once they’re finally all back I’ll be able to start verifying them. The verification is to ensure that the parts have been machined in accordance to the drawings. The machine shop also finished with the vacuum ports so I can fit check those once the end caps come back.
I’ve started working on taking inventory of all the wire. It’s certainly taking longer than I thought it would since what is written on one document may be different than what is written on another document which both may be different from what is actually labeled on the wire. Once it’s all sorted out though there will be a nice wire list. Some of the wires are being replaced so we need a list of what kind of wire is connected where. That way it’ll be easy to look at the list and say ‘we need to replace this type and it’s used in these locations’.
Though no longer on the sub, these are some of the wires I am taking inventory of. And yes, they still look like that.
We left the dock at 8am on monday morning. Once we were out of the channel we went to our normal cruising shifts. Everything was going pretty smoothly till tuesday night. I went down to check the port engine room. I saw water spraying out from around the propeller shaft and the water was already at foot and a half deep. It was all the way up to the bottom of the engine and the gearbox. I went and alerted the crew then went back down to the engine room. I shut the engine down then located the source of the leak. Our propeller shaft dripless seal had failed. Lots of water was pouring in. I was able to clamp the two parts together with my hands to stop the water till the crew and engineer could come down to help. Once help arrived Don and I worked at stopping the leak with clamps and the crew got to work pumping the water out. It looked like there was no damage to the seal, it had just come loose for some reason. We worked all night and the next day to try and get it back together. But everything had to be perfect to get a good seal. We didn’t have all the tools or knowledge to do this on our own. So we had the technician that installed the coupling while we were in the Tampa shipyard come to Fort Myers to meet us. We picked up the tech in our small boat and brought him out to the ship. With his help the three of us fixed the seal. We did a sea trial and then brought the tech back to Fort Myers. After that the rest of the week went pretty smoothly. 
I finished soldering my circuit boards! I made two so that they can be hooked up to each other and tested. Working on the boards was an effort since the components are tiny but working under a microscope certainly made it easier. After finishing up with the soldering, we tried testing the boards. So far it isn’t working but I think it’s a problem with the headphones we’re using and not the boards.
Outside of soldering, I’m still working with the pressure housings. I’ve definitely gotten my steps in walking up and down the stairs from the lab to the machine shop carrying the chunks of titanium. But the good news is that the work is getting done quickly so the housings can be reassembled and pressure tested.
My microscope soldering station
One of the resistors
My finished circuit boards