Messy Business, but you cannot ignore the results
Stuff we used:
More Schmoo: Aircraft Spruce
Lots more gloves: Home &($%#
Red Dye 40, which to the layperson, it is more commonly known as simply disodium 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-2-naphthalenesulfonate: Sigma Aldrich
A white cloth: Joanne’s fabrics: Norwich CT
2X12: Riverhead Building Supply Niantic CT
Podavelle 4AN Female Flare Cap Port Plug Block Off Fitting: Mr Bezos
Podavelle 6AN Female Flare Cap Port Plug Block Off Fitting: Mr. Bezos
Not too long ago, top authorities had given a lot of attention to using water boarding as a wonderful activity to get to know their personal collection of ne’er do wells. The subject even reached the White House, where it’s merits were bantered about amongst the Cabinet. With time it became better understood that it was like using a jack hammer to push a pin through a wedge of hot brei cheese, ineffective, and makes quite a mess.
We mention it here after watching an obscure interview on the YouTube of Dick Cheney done by Erran Morad a sad, obscure Israeli journalist lacking in eloquence and quite frankly, possessing all the comportment of a Borat wannabe. The interview starts out covering Cheney’s career as Defense Secretary and migrating to the subject of water boarding, culminating in Cheney autographing Morad’s personal water boarding kit. While Our Dear Inspiration and sage The Lord Slingungus does not see the merit of using waterboarding to break the conversational ice, he cannot disagree with, nor ignore its usefulness to test the integrity of our fuel tanks.
We start our post tank construction integrity testing by following the word of Mike Blythe himself. Now, as with any other book of hallowed and precious verbiage, changes happen over time, and now there are many versions of the Sling Legos Book. We like the latest Attorney James Esq. Version, all others should be consigned to the dumpster fires of Paris. The real, and proper version of March 22nd 2022 enlightens us in the word of Mike Blythe with an extra special message on page 44. We shall quote it here:
“After the fuel tank has been assembled and the sealant cured it must be tested for leaks. Close all openings and connect a pressure gauge to the drain and pressurise (sic) the tank to 0.1 bar. Apply soap water over all joints, rivet heads and overlapping areas for possible leaks and inspect. Take a reading from the pressure gauge and leave for at least 1 hour. After 1 hour make sure that the reading on the pressure gauge is still the same as previous reading. Assemble fuel tank onto the wing and redo these steps and inspect for any leaks before painting the fuel tank or wing.”
This is the word of Mike Blythe,
Amen.
“Once more onward to Osh Kosh, dear friends, once more;
Or Ply the Skies up with our Sling two and TSi.
In flight there’s nothing so becomes a man
As crossing ocean wide and over mountains high…”
This one shouldn’t be too hard a commandment to follow. The first thing mentioned was to close all the openings. We tried a few ghetto grade methods involving a rubber hose, rubber gloves and tape.
Well, The Connecticut Slingers Directorate of Web Standards has issued a decree that the things we did with all that stuff is best left unwritten, sorry folks. Suffice it to say we quickly found the best way would to be use 4AN and 6AN flare caps with United National Fine Thread (UNF). So off we went marauding across the winter wasteland of southeast Connecticut raiding whatever auto parts and hardware stores we happened across. All, Even the venerated Montville Hardware, were not spared our ransacking for end caps that would fit. Alas, we retreated to our Sling Build Headquarters (SBH) empty handed, cursing the heinous engineer that created that most wretched UNF threading. We did an after-mission investigation and found that in the world of screw on fasteners, fittings and threaded what not, there are 19 different thread styles. This is against the rules of nature right there. a number this big means the Government must be involved.
We had no choice we would have go to the Jeff Bezos fencing syndicate where we found a 6AN Female Flare Swivel to 1/4 NPT Pipe Male Adapter Fitting Union to convert the beastly UNF to the more civilized NPT. We would complete the arrangement with a Female TEE that would hold a gauge and a Schraeder valve on the other openings.
With the parts procured, and the ports were capped, we fired up the air compressor and waited for the gauge to start going up. The Glorious part of this is finding that the left tank had just a small undetectable leak somewhere because the gauge did indeed reach 1.5 PSI, Happy Joy! all we needed to do was figure out where. The right tank, however, was disappointing. We hooked our gauge up, capped off the openings, fired up the compressor and waited. Then we waited some more. Next, we sat with our beverages, and waited. and waited. and then waited a little more, all the while the air compressor screamed away. We must have waited a good solid 20 seconds, which in Today’s TikTok McDonald’s Drive Through feed me now generation, is more than sufficient?
A few seconds later, we figured it out. We had leaks to fix. Fortunately, the leaks were at the ends, two at the outboard end, another at the inboard. Pinpointing exactly where was a bit difficult since our inspection mirror could not fit through the fuel filler hole. We will put in a request to Mr. Blythe for a larger fuel filler and an orange ball to stick on the VOR antenna to make our Sling easier to find amongst all the other Slings on the ramp.
We resorted to lowering a flashlight into the dark but not bottomless void of the tank and looking for the light peeping out of the holes, which proved to be surprisingly effective. One leak was down deep at he bottom, the other was behind the filler cap near the fuel overflow vent. They were at where the back channel (P/N WG-CHL-015-R-F-1) is riveted to rib 216 (P/N WG-RIB-S26-R-F-0) and Rib 2 (P/N WG-RIB-S22-R-F-0). The hard corners in these ribs have gaps between the teeth were hard to fill with the shmoo. These would be the hardest since even our child labor doesn’t have hands small enough to reach through the fuel filler to apply the shmoo to the leaks. We would need to resort to special tools.
Taking our inspiration from the gifted and wizened tool makers residing in the Corrigan Correctional Institute, we fabricated a Manually Operated Shank-like Shmoo Application Device (MOSSAD) out of a piece of 6 gauge wire left over from hooking up our golfcart charger. We carefully used that to hook around the filler hole to apply the shmoo to the offending holes. Not overly difficult, but tedious.
With that fixed we moved on to the other end. The good thing about the inboard was the nice gaping hole used for the fuel level sensor. It made it easy to stick our hands in to massage the shmoo gently and lovingly into the offending holes, we didn’t even have to consider using small handed child labor for this.
We waited a week before doing another check and found just a teeny slow reduction in the pressure on the gauge, not unlike the left wing. We weren’t sure if it was leaking from the Rube Goldberg setup that we used for connecting the gauge, or if it was hard to find teeny tiny one somewhere in the plethora of joints. Regardless, any air escaping from the tank is about as welcome as that escaping from a walrus that just binge ate the entire remnants of a cabbage and bean freighter that had run aground on its rock. We tried rubbing pipe snoop all over the tank to find it, but it was fruitless. Nothing to do but resort to more drastic and, let’s just say, more enhanced measures.
We extraordinarily renditioned the tanks to our top-secret location where we had the High Availability Manifold Aqueous System (HAMAS) which we would use to carry out the inquiry with a straightforward, simple but very effective method, which would generate irrefutable results that could not be ignored, just like when we filled the tank with water the first time.
The Equipment was simple, a pair of tables with a 2X10 resting on them. To protect the subject from permanent revelatory marks, we provided a 1-inch-thick foam rubber pad on top of the board and covered that with a white piece of cloth, to catch any fluids. It was prepared.
Once we got the tank splayed across the white sheet, we dumped some powdered disodium 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-2-naphthalenesulfonate which is more technically known as Red Dye No.40, and filled the tank with water. And waited.
Think about it, it is clear we are milking this here, trying to fill space with blather and make the process look highly technical and difficult. We apologize for insulting your intelligence like they do on TV, (but not like on the YouTube). We will spare you further trouble and cut to the chase. We left the tank overnight and checked it the next morning. Indeed, Water boarding is a messy business, but we cannot ignore its effectiveness at where the leaks are. There was only one little dribble, where the level sensor wire comes out. a tightening of the nut holding the wire on would take care of that. Yippity Skip Hoozah! Let jubilation rein.
There wasn’t much to do after draining the water out, except put the tanks on the wings so they wouldn’t be kicking around in the garage getting in everyone’s way.
This proved easier than we thought, just a couple of annoyances. Trying to slide the tank head-on on to the wing makes the edges of the sheet metal catch and butt against one another, and it is hard to get the holes to line up front to back and side to side, what with all the congealed shmoo in the cracks creating all the friction.
The best way we found was to start at the outboard end. We used a pair of awls to align holes in the top and bottom of the tank and wing. They served like a nice hinge pin so we could do a scissors swing kind of move to make the tank skins overlap the wing skins. The strap trick came in handy to squeeze the tank the rest of the way on, and it worked great, and we had the tank Clecoed and riveted on quicker than Bagdad fell.
Next: Flapping in the Breeze