8 hours of High Powered Fun.
Stuff we used:
MIL spec 223759, wire 12 and 16 AWG Jan’s Electronics
Tubing cutter and bender Montville Hardware
Pitot tube connecting kit of stuff Steinair
The Hunt for Red October. U-571. Das Boot. Movies like that and countless YouTube videos show some of the parts of submarines on the $50 dollar tour. But there are lots of unforgotten but no less essential systems which don’t get talked about, like the shuffle board courts, or the casino where the Navy can recover some of its labor costs on those long voyages. Powering all of that is the nuclear reactor part of the boat where little chunks of Uranium are turned into electricity. It’s not like the ice cream machine or the torpedo room bits. It is such a drab and unexciting part of the ship that no one likes to really talk about it. but let’s not forget how essential it is. nor the people that run it. Let’s not forget about the poor fireman who has to spend his entire 6-hour watch shoveling the uranium pellets into the blasting blue glowing beast. On every Mortal Combat tournament night in the boat’s game room, he pauses (okay, yes this is the 21st century, women can be the fireman too) mops his brow and wishes someone would hurry up and kill off Shang Tsung already. But the gaming goes on, and one arm bandits keep spinning their wheels, all driven by the electricity. Electricity generated out of uranium but transmitted by wire. Lots of it.
Top Secret! Don’t tell any one this is a top secrete design plan of a Nuclear Reactor in a Submarine. Shhhhhhhhhhhhhh!!!!!!!!!!
Here in Southeastern Connecticut, our local submarine proprietor, Electric Boat is a quiet neighbor, polite, keeps to itself, and doesn’t share its interests with the neighbors much. But we have it on good YouTube authority that they use over 250,000 miles of wiring in a submarine. We have yet to find out how much more they use in the higher trim models, the ones with the power windows and electrically heated travertine floors in the spas. it’s a secret. Nevertheless, it takes a lot of wiring to get electricity from the reactor to the electric train symposium in the ship’s ballroom on Deck 3 and all the other cool stuff. And not just any wire. Oh no! it’s the Military. It can’t use the Walmart stuff Radio Shack would’ve sold, that just wouldn’t do!
This puts Submarines almost in the same lofty league as Slings. they both need expensive special wiring, ordinary off the shelf stuff wouldn’t do ‘cause it has such a low price tag. To help boost the price for itself, the Military came out with a 43-page treatise of gobbledygook telling itself what wire is. It goes by a nice warm inspiring title: MIL spec 223759, with numbered paragraphs with titles like “Quality Conformance Inspection of Finished Wire”, and “Post Flame Dialectric Test”, sounds expensively irrelevant.
The good part comes at the beginning, which was about all we here at Connecticut Slingers could stand reading.
This specification starts out talking it up used car sales like. It’s fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel coated conductors of copper or copper alloy as specified in the applicable specification sheet. The fluoropolymer insulation of these wires may be tetrafluoroethylene (TFE), fluorinated ethylene propylene (PEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene (ETFE) or other fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials. Lovely reading for a long commercial flight.
The point is, all of these plastics contain some sort of fluoridated carbon-based plastic which is really great at holding its own heat in. Heat is not a big deal in South Africa where the Penguins live, but here in Scorching New England, those dog days of summer turn wings into nice roasting ovens. (Clever idea not to try: stuff a potato into the pitot tube inspection panel the in the morning for an inflight snack after your first fuel stop The good thing about the MIL spec 223759 wire is its ability to bear heat up to 200◦ F. Plus, in the wintertime, it can take the cold, as low as -55◦C, for when we go to visit Grandma in Northern Maine.
Some examples of Flourocarbon plastic coating formulas
From this we get a nice heat tolerant plastic. Well matched for everything from coating the beryllium tampers of thermonuclear devices to coating our special wire with its 43 pages of approving drivel. It even comes in a variety of colors.
The Left wing has the Pitot and its own set of lights. To do those, Tedderfield sent some wire with the kit. some of it came in a gray cable that’s shielded, so the blinky strobe lights won’t make annoying noises in our earmuffs (Chester Greenwood didn’t think of that), and the ATC can’t read its signal. and the rest is some white 16 gage with the required MIL spec 223759 printed on it. We used that for the taxi and Landing lights.
Not much has been said in the writings or videos, except for Evan Brunye, in his brilliant Emmy worthy episode where he fathomed its use. We followed the pictures in the Legos instruction book, running the two sets of wires down the Lower Wing Stringer (P/N: WG-STR-003-L-F-0). The stringer is riveted to the bottom skin, and as we cruise along, the wires will rattle and chafe against the rivets. The folks at Tedderfield thought about this and put holes for cable ties spaced down the length to secure the wire. For additional peace of mind, we sheathed it in some of the same nice, braided cable sleeve we used for the empennage wiring. It is a bit big for the wires, but it pads around them well enough. Still, stuffing them down the sheathing needed the right technique, otherwise friction builds up and slows the progress. If you pulled on socks, you can figure it out. One thing we overlooked before installing the bottom skin was the plastic grommet edging on the ribs where the wing stringer runs through. Fortunately, we could wedge the edging into place. We will remember to put them in before the bottom skin on the right wing.
The lower stringer at the left has the wires enclosed in the braided cable sheathing. the red and white air lines and the wires for the pitot tube are at the right
The lower stringer at the left has the wires enclosed in the braided cable sheathing. the red and white air lines and the wires for the pitot tube are at the right
The next bit of wiring came with the Garmin G-26 Heated Pitot tube, all the rage amongst Slingers. This is a variant of one of those Unknown unknowns. You know that you should know, but still don’t, until you happen to wonder if you do know. We initially thought 16 AWG would be sufficient, and so we got some additional 16 AWG wire through Jan Electronics, our local purveyor of electronical electric stuff to Electric Boat.
It wasn’t until we had the wire wrapped up in PET braided cable sleeve and ensconced in the wing ribs that our operative, on a fact-finding mission at The Airplane Factory asked if we had the right sized wire. Mssr D’assonville looked it up, and found we needed 12 AWG. Brilliant, really smart. Install first then ask. Good move right there! This is why we are not building the thing starting from bauxite. No need to tell you what we did next.
The cable sleeve was great for running the light wires up to the end of the stringer, but that was where they had to part company, with the shielded 6 wire cable going to the NAV lights leaving the three loose wires for the taxi and landing lights. The cable sleeving was to big for the three wires, and we still had to thread them through the main spar and into the Forward Illumination Units ( FIU) chamber. We saw this problem as a wonderful opportunity to flex our wing interior decorating chops. We spied some lovely blue wire shrink tubing at Jan’s. We have to confess that we originally used black tubing to do the job, but our sensibilities won us over and we swapped the black out with blue, so now we have good old red, white and blue flying with us! Plus, we also got to use the heat gun, always a good source of fun on those cold winter days.
The Blue and the Gray. The blue shrink wrapped wire on the left leads to the Forward Illumination Units (FIUs).
The Pitot hook up stuff includes comes with clear vinyl tubing for running the air from the pitot tube to the pressure transducers in the analyzer. This is perfectly fine and works great, though it’s hard to think why anyone would like to watch air going through a tube. There is also a bit of psychological turmoil going on with using safety wire to secure tubing to the ends of the Pitot tube. It just looks, well, frankly speaking, somewhere around the -3,857 level on the Ghetto Grade Scale and evokes an image of a Cro-Magnon era stone spearhead held onto a shaft with the odd bit mastodon sinew.
Then we looked at what Phil Rueker did with the push to connect fittings and ¼ inch tubing. We wanted to do it to. We could have spent a lot of time in digging around on the internet to get the right fittings but being members of the McDonald’s-drive-through-feed-me-now generation, we found a Garmin GAP-26 connector kit at Steinair, ogled, dreamed then splurged. We got it a few days later, and found it came with red and white tubing, but no blue. This is a real attack on our ‘Murican red, white and blue color troika. Not to worry since the FIU wiring could be wrapped in blue.
The kit also came with a whole bag of doodads, fittings, tie wraps, and whatnot. Hidden in that bag of stuff was a pair of anodined Hindenburg blue compression to push to connect fittings to adapt the aluminum tubes coming out of the pitot tube. The compression fitting gets its name from a beveled ring and special nut which slipped over the tubing and tightened, squeezes the aluminum tube when the nut is tightened. Rather cruel to the tubing, but it makes a nice seal. The plastic tubing would just snap into the push to connect end nice and snug. Easy as making a Kraft Mac and Cheese Dinner, And we are talking Velveeta.
The real challenge was bending the aluminum tubing. We could have cut the tubing short to stick straight up out of the pitot mount and shove a 90◦ elbow on it and declare victory. That would work OK, but the GAP-26 manual says we should have about 8 inches from the hot pitot tube to plastic. Equally important, the cold hard 90◦ angle doesn’t really match the gentle sweep of the leading wing edge, and thus could ruin the interior decorating aesthetics. Bending it, we would.
The tubes are a bit on the narrow and delicate side, and that would make the potential for kinking them lurking around. To prevent this, the boys at Montville Hardware set us up with a tubing bender and some springs that were just big enough to slip over the tubing to form a cage around the tube. The idea was to keep the tube’s barrel-chested figure nice and svelte as it got bent in a tubing bender. It worked nicely, and we got the tubes bent in a lovely sweeping graceful bend in keeping with the bends in the wing skins and ribs. We could then install the fittings and connect the red and white plastic tubing. The tubing went in easily enough, threaded through the grommets in the wings and pushed into the quick connects. It brightened up the place when accessorized with the blue anodized compression fittings. But we still needed more blue. Fortunately, we found a way to add in some more, and solve the wiring problem at the same time.
Pitot Tube Mount, mixed media. The lower left shows the gentle graceful arcing sweep of the aluminum Pitot tubing which draws the eye out of the chaos of the G-26 wiring to the red strident order of the sheathed wiring and tubing which briefly spans the vomit green of the wing interior to disappear in the rubber grommet. The artist is trying to show the order in life denoted as green, emerging from chaos only to disapear into mystery (grommet).
The wing needs electricity for the pitot heat, NAV lights, and landing lights. We can manage to keep the wires for the pitot heat under control and protected all the way up to the connections with the control box by passing it through the gromets in the ribs.
The lighting is a different matter. The Nav and strobe lights need even more to go through the composite wingtip so we made the gray cable long enough for that, but the FIU wiring was a loose collection of wires which needed to be bundled somehow. We thought of the shrink sleeves that we saw down at Jan’s Electronics in New London. they he had a whole rack of different sizes in a variety of colors and sizes to choose from, so we made a mistake and chose black ‘cause we did not know better. We saw the mistake, and fixed it, changing the black over to blue which we slipped over the FIU wiring and shrunk in place with a heat gun.
This is the black shrink wrap, we changed it to blue to match the red and white pitot tubing.
With the wiring out of the way, we have the hole for the GAP-26 and pitot tube inspection hole to drill. This is one of those fun jobs, even better than the alodining. We carefully measured it, and at 57/8”, we could have slapped a hole saw onto our 18V ½” drill and have at it, but a hole that big was definitely in HoleHawg Territory. Seriously, it’s the principal of the thing. And there in is a problem. On the one hand, if you are the average Slinger, your chances of having such a toy like that lying around is about the same as Mike Blythe inviting you to observe his next BRS demonstration. Which means we would have to shell out for one, spending the equivalent of a pair of Whelan Blaze Wingtip lights.
On the other hand, if we didn’t, we would be violating the Suburban Man’s Creed: A Man Cannot Have Too Many Tools. This is yet one more difficult dilemma.
The solution is found in the ever-deepening archive of Sling Videos and Treatises of Sling Hole making. With enough googling, and as the Duck Duck Goes, we found the beautiful and moving work of The highly skilled Phil Rueker. he chronicles his use of theDicfeos double headed cutter, model DIC001, and includes a video of himself deftly cutting a hole with elegant dispatch. We felt the same fevered desire gotten after watching a late night TV infomercial. We wanted one. It was a good deal cheaper alternative to the Hole Hawg setup, and we would fulfill the Suburban Man’s Tenet.
You can get an idea how it works, the large goiterous mass at the bottom of the picture fits into a drill. the drill drives a shaft that goes up and down in the housing. the shaft has a well machined notch that acts like a scissor blade that chews off chunks of metal as it moves around the circle.
This really needs its own Infomercial.
Using it is straight forward. We had to find where to drill the hole, and we referenced the instruction sheet Phil astutely included in his blog entry which shows where the treasure is supposed to be buried.
Well we were itching to try it. So we laid out where the center of the hole would go using the dimensions on the diagram we found on Phil’s site. Next we used a compass to draw a circle around the center hole that was the size of the cover. With that, we could drill the two required holes, a 4mm for the center, the other 10mm one is more difficult, since it had to be drilled with the edge of the hole just touching the inside of the circle drawn using the compass. With our resident ham-fisted gorilla technique, we managed to get it the finest chinchilla hair close, so you can too. Next we could make the hole. This was where it looked just a bit easier than it was. The heavy drill and the ungainliness of the affair made it a little tricky.
The trick was to keep the guide shaft nice and level, not pull outward against the centering pin and move the whole drill and cutter head in unison as it gnawed away at the metal. That said, we won’t go into all the gory details, as it went pretty fast. We guided it around keeping it lined up with the circle we drew, the drill drove the shaft with ravenous fury. As it moved up and down, it bit off chunks of the metal sheet like a meth/crack fueled hippopotamus that had just smoked an unreasonable amount of Cannabis would attack 3-and-a-half-ton pile of river grass. Sadly, with it nawing and chewing away so fast, we didn’t have time to get any photos of it working.
Our aim point
While we do not have step by step photos, we can assure you, dear reader, that as luck provided, we had a perfect hole that fitted the cover plate perfectly. We assembled a cover with the bayonet mount, including Inspection Hatch Grip on Plate (P/N WG-PLT-014-X-F-0). Next, we fitted this into the hole, and used it as a template and guide to drilling the rivet holes, dimpled and then riveted the plate in place.
Needless to say, we were utterly astounded that our handy work turned out so well. We admired it for a while, then got back to work.
Next time: Getting Tanked.