Deburring Left Tank Parts

No Proseal work tonight, but its close.  I need to get the left tank up to the same point as the right, which means breaking it down, deburring, finishing the edges, and then dimpling.  First I need to trim my vent tube, and flare it for its fitting. I measured and marked the tube where it goes into the bulkhead fitting, and then trimmed it using a tubing cutter.

I used a Parker flare tool to make the flares perfect.  This tool makes it really easy to get a nice and perfect flare every time and its simple to use.

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Finally put on the fittings and done them up finger tight so that I could measure and trim the very far end near the outboard of the fuel tank, where the fuel cap is.  I left a good bit extra on this tubing, so I needed to trim a decent amount on the end.

Once that was done, all that was left was to disassemble the tank and get the parts ready for deburring.  I started deburring all the small parts first, and I made pretty decent progress before I decided to call it a night.  Since I used a reamer on most of these holes, the deburring process went really quickly, and with much less effort.  These are all the parts I was able to get deburred tonight:

All that I have left to deburr is the holes on the ribs.  Then I’ll follow all the pieces up with some edge deburring to get everything ready for dimpling.  I still need to deburr the skin though.

Thats it for tonight.  Decent progress on these parts.  I’d say I have another hour or two of deburring and edge finishing before I’m ready to dimple these parts.  Then its scuffing for sealant, and then sealing.  Lots of work going into these tanks!

Google Photos Link: https://photos.app.goo.gl/hFeupKe9wpfhHRMD8

Hours Worked: 2.0

Sealing the Right Tank Drain and Fuel Cap

Another proseal session tonight, but this was a pretty short one.  This stuff is still messy, and I still have a hard time dealing with it, because I am not good with messy stuff!  I wanted to get the tank drain, and the fuel filler sealed and ready to go, since the next steps after this will be installing the ribs.  I started off by scuffing up the areas I wanted to seal, and then cleaning those surfaces REALLY good with acetone and MEK.  After that, I used some masking tape to prevent me making a mess in places I didn’t want sealant.   More specifically, I wanted to mask off the interior part of the tank around the tank drain to leave little draining channels clear so that water can get to the tank drain with no obstruction.  Here is how I did that:

Then I suited up with some gloves, and mixed up about 2 ounces of proseal.  I decided to get the tank drain done first since it was small and easy to get to.  So, I applied a decent layer of proseal onto the tank drain fitting itself, and then cleco’d it onto the skin.  This made things less messy, with only a little squeezing out the sides.

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After I got the tank drain clecod on with its sealant I decided to do the same for the fuel filler, and then move on to riveting.  This way I had at least got the sealant applied and clamped down to both parts.  So, I did the same, applied the sealant to the top of the fuel filler flange (the part that mates with the skin), and clecoed it on.  Granted, these parts were also scuffed and cleaned earlier in this sesison.

I sloshed some rivets around in a jar of MEK to get them nice and clean and then dried them on a clean towel, and squeezed them all into the tank drain first..  I was able to use my squeezer on all of the rivets on the tank drain pretty easily.

This was a messy job, as proseal was getting all over my squeezer and clecos.  But thankfully, it cleans up really easily with MEK. Here is the exterior of the tank drain, after I riveted it, and cleaned up all the proseal.

Next up, I put a dollop of proseal on the backside of each rivet on the inside of the tank to help them seal.  Once I was happy with the dollops, I removed the masking tape, and cleaned up the area to provide the water drainage channels for the tank drain.  I used some q-tips soaked with MEK to make this process easier.  I also made sure to fully clean all the goop out of the threads of the drain.

 

This isn’t the most neatest of jobs, but its very functional.  I am just hoping I am getting these things sealed good! Next up I moved on to riveting the fuel filler flange.  This was TOTALLY messy, and I did not get any photos of me during the process because my hands were essentially covered in proseal.  I was able to squeeze maybe 6 out of all these rivets, I had to use a bucking bar and rivet gun on the last few because my squeezer wouldn’t reach them.  Then, after I had the rivets set, I smeared a good coat of proseal over the entire inner surface of the filler flange.  This was probably overkill, but I figured why not?  Might as well be sure that this thing is gonna be sealed up nice and tight.  This is how it looked all messy, before I cleaned it up with some MEK and paper towels

And here is the outside view AFTER I cleaned up all the excess proseal.  You can see the faint black line on the inner side of the filler flange that is helping keep this sealed.  The rivets look nice and flush and what you are seeing is the scuff marks from where I scuffed the dimples.  These will get buffed out when its finished for painting.

That wraps up this proseal session.  I had some excess left, so I would say 1 or 1.5 ounces would be plenty to do the filler flange and tank drain.  I’ll keep this in mind when I do the left tank.  I left the tank in the tank stand / jig to help it hold shape while the filler flange dries, since its formed around the leading edge curve a bit.  I’ll leave this as is for a few days to cure and dry, I still need to prep the left tank and get it ready for sealing.

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Google Photos Link: https://photos.app.goo.gl/PeBtsgKAZdjoCTBM7

Hours Worked: 1.75

Sealing and Riveting Right Tank Stiffeners

Its time.  Time to start working with this sticky, smelly, nasty sealant again.  I have not really been looking forward to this, but it has to be done.  My right tank has been scuffed and semi-cleaned in the last couple of build sessions, so I wanted to give it another quick scuff and clean it really well with MEK to get a good bond with proseal.  After I had the skin all cleaned and scuffed, I did the same to the stiffeners.  I pulled a big scoop of AN426AD3-3.5 rivets and put them in a glass jar with some MEL to soak off any manufacturing residue.  I’d give them a shake every now and again to agitate them around.

Next up was to mask off the area to help make clean up easier.  Plan old masking tape worked good for this, and I left enough room for the filet around the stiffeners.

I mixed up a batch of proseal, using the 10-1 ratio.  I mixed 120 grams of one part and 12 of the other, and then made sure it was all nicely mixed together.  I dabbed. little bit of sealant into each dimple to help seal the tanks, which made a big mess, especially trying to put rivets in there.

Eventually I managed to get a rivet into each hole, making a hell of a sticky mess.  I double gloved so I could switch out my gloves easily.  Once I had a rivet in each hole, I slapped on some masking tape to act as back rivet tape.

Now it was time to smear on the sealant on the inside of the skins.  I used a cheap paint brush, about 1/2″ wide, and I cut the bristles down very short to make spreading this thick goo easier.  I did not get any pics of this, because I was an utter mess, gloves covered in this stuff, and I didn’t want to get it on my phone. Once i had a good covering of sealant where the stiffeners go, I placed them over the rivets and pressed them into place.  I pulled out my back rivet plate, positioned it under the stiffener and used a back rivet set on my rivet gun to set the rivets.  I had to work a little fast here because my sealant was starting to harden, and I am inexperienced so I didn’t get many pics.

After I had all the rivets set, I came back over with some popcicle sticks and formed my filets around the stiffener edges, and used the extra sealant I scooped up in this process for the little dabs that covered the rivet tails. This was super messy.  I think I used a little too much sealant! hah.

The pic above is after I pulled the masking tape off, during clean up.  Like I mentioned, my gloves were covered in this stuff, I didn’t want to chance getting it on my phone.  But, even though this was my first time, and I spent more time on it that most people, I think it came out OK.  I am just hoping its sealed up nice and tight, and I wont know until I do some pressure testing.  I pulled the rivet tape of the outside of the skin, and cleaned up the excess sealant with some MEK.  MEK really does a good job of cleaning this stuff up.

You can just barely see a small little black area around the rivet head where the sealant squished around it.  The excess cleaned up nicely.  I’ll put lots of photos in the gallery below of how they came out.  Fingers cross they wont leak! I’ll let this harden a bit while I work on deburring and dimpling the left tank and getting it ready.

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Google Photos Link: https://photos.app.goo.gl/o58XDci9wEmcCkg9A

Hours Worked: 2.25

W-423 Splice Plate Finishing

I changed it up a bit tonight.  I realized I could go ahead and knock out the W-423 splice plate since it needed a little more work per wing.  These are the small strips of aluminum that are used as reinforcement plates between where the leading edge and the fuel tanks butt up against each other.  I started out by drilling the holes for the screws (at the fuel tank end) out to a #19 per the instructions.

Once I had my holes drilled, I deburred all the holes on these plates since I had not done that yet, and my new holes needed it too.  After they were deburred, I have to drill the rivet holes for the nutplates that go on the back of the screw holes to captive the screw.  I don’t have a fancy nut plate jig, so I had to do it the old fashioned way.  I screwed the nutplate on with a screw and then lined it up so I could drill one of the holes for the rivets.

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Once I had the first hole drilled using the screw to hold things in place temporarily, I clecoed the new hole to hold the nutplate tight into place, then I drilled the second rivet holes.

Once I had these new rivet holes drilled, you guessed it…it was time to deburr these holes as well.  Next up was to dimple the #8 screw holes, and then dimple the #40 rivet holes for the nutplates.  I went ahead and dimpled the other #40 holes since these will be getting AN426AN3-3.5 rivets when it gets riveted to the leading edge skin.  This went quick on the DRDT-2 dimpler.

Finally, it was time to rivet on the nutplates.  Like usual, I clecoed on hole of the nutplate, and then squeezed the rivets in place using my squeezer.  Pretty easy work with these nice tools I guess.

After I had completed one W-423 splice plate / reinforcement plate, I moved on and did the exact same thing to the other wings.  I think I did the left one first and then the right. Thats it for this quick build session!

Google Photos Link: https://photos.app.goo.gl/pSD1JdiEWEJGkeYB6

Hours Worked: 2.0

Right Tank Deburring and Dimpling Part 2

Another semi-boring build update.  I’m still working towards pro-sealing these tanks, and the right one is pretty much ready after tonights work.  I started out by finishing up the last remaining deburring on the ribs, which wasn’t much, the pile on the left is what I had left to get done.

Once I had the ribs deburred, I decided to start deburring the skin.  This meant I needed to remove some strips of the protective plastic so I could deburr and dimple them.  I like leaving the plastic on as much as possible to protect the skins whiles they are in storage.  I used my trusty old trick of a blunt soldering iron to melt a line in the plastic making it easy to remove.  I also found that the leading edge reinforcement strip makes a very nice template and guide for the soldering iron! I have it clamped on the skin in the photos below as a guide.

After a few minutes, I had the plastic removed and the skin was ready to be deburred……and it has a TON of holes in it!

After I got the skins holes deburred, I used a bastard file to round off the corners, and then smoothed the skin edges with a scotchbrite pad.  That essentially finished up all the deburring, edge deburring and cleanup on all of my right tank parts, so the next step was dimpling!  I moved my DRDT-2 dimpler over into position and pulled up a comfy chair and started working on dimpling the stiffeners while I enjoyed some music and coffee.

After the stiffeners were all dimpled, I moved on to dimpling the ribs.  Same process here.  I used the DRDT-2 to do all the dimples.  The only caveat was there was a couple holes near the very corners that I couldn’t get with the DRDT-2, so I simply put the dimple dies in my pneumatic squeezer and dimpled that way.  These went really quickly, just like the stiffeners.

I decided to get a good initial scuffing on the inside of the tanks where the ribs and stiffeners would get prosealed, BEFORE dimpling.  I am a big fan of scuffing before dimpling because the smooth surface doesn’t tear through your scotchbrite pads as quickly as the dimples.  So, i gave each row a really good scuffing.  I’ll dimple these, and then do one last final easy scuffing to clear away corrosion and grime before prosealing.

Once I had the skins all nicely scuffed, I gently cleaned the grit using some acetone, being careful not to wipe away my marks.  This was just to keep grit and scuffing dust out of my dimple dies.  I’ll clean them way better before prosealing.  The dimpler made pretty quick and easy work on these skins, its well worth its money!

You’ll notice some holes dont get dimples, like the long row running foreground to background, and the sump drain holes.  The long row is where the baffle goes, and the skin is machine countersunk on the outside instead of dimpling so that the baffle will slide easily in place when its gooped up with proseal and final sealing.  The sumo drain is like that so that water drains directly into the sump.  After I had the skin all dimpled, the right tank is now ready to be sealed and riveted!  Finally making progress on these tanks!

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Google Photos Link: https://photos.app.goo.gl/Bbger4QMJTC8NAiq5

Hours Worked: 3.5

Right Tank Deburring Part 1

This is a quick build update as there isn’t much of an update.  I disassembled the right tank and then removed the plastic from the parts so I could start the arduous process of deburring, edge finishing and dimpling.  I logged a little over an hour tonight, and that was mostly deburring all the holes.  I did one piece at a time, deburred the holes then deburred and finished all the edges of that part before setting it on the shelf as completed.  I got through MOST of the parts, except for a half dozen ribs or so, and then called it for the night.  I did a little shop cleaning afterwards, but I am not counting the time spent cleaning the shop 🙂

Here’s the parts after disassembly and ready for deburring:

This is to be continued in the next build session!  Thats all for tonight.  Super simple.

Hours worked: 1.25

Right Tank Resistive Float Sender and Vent Line

More progress made on the fuel tanks tonight! I picked up with the right tank, and I wanted to get the vent line trimmed and finished.  I had left it a little long so I could trim it down to size once I bought a tubing cutter.  Well, I remembered to stop by Ace Hardware today on my way home from flying a PA-11 Cub and bought a decent little tubing cutter.  I spent a good deal of time playing with the cutter as well as my Parker flare tool that came in my tool kit, learning on scrap bits of tubing until I felt confident at making the cuts and flares on the actual parts.  Here’s the carnage from my little learning session.

Eventually, I got brave and made the cut on my vent line for the right tank.  I measured roughly where I’d need to cut the tubing to line up with the bulkhead fitting, and then made my cut.  I can still push the excess tubing out to the outboard side, and just trim there if I haven’t made a precise measurement, so no real worry.  I am pretty happy with the way my first official “production’ flare and fitting went!

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I have about an inch of extra I will need to trim on the outboard side, where the vent attaches to the clip on the filler neck, but thats an easy one since theres no fitting thats go on it.  I marked where I think it should be and trimmed it with the cutter.

Then I put all the ribs back on the tank, and did my first official test fit.  I only went finger tight on the fittings just to see if the alignment and flares were good, and I am pretty stoked about how nice it looks in the tank!

The next thing I wanted to tackle was fitting the resistive float style senders.  Since I don’t have flop tube in the right tank, I can use the traditional method of installing the sender as outlined in the Vans plans.  So I pulled the sender from the shelf, making sure I had the proper one, as there are two different senders and they are specific to each wing.  After double checking against the plans, I grabbed the F-385C sender. This is what comes in the box.

Notice the float arm is straight.  We need to bend it per the plans with a 3″ arm, then a 90′ degree bend with another 3″ section.  Like this:

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Heres the kicker! The plans don’t tell you that you need to bend another 90 degree turn that slots into the sender body to hold the arm! I would not have caught that but I was reading the instructions that came with the sender and noticed that we need a 0.6″ bend to slot in the body.  So, I measured things up, and made the bends.  This is how it came out.  Notice the little bend at the end of the float arm!  I did have to trim the excess off with a hacksaw and then ground the end down nice and smooth.

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Once I had the arm bent into shape, I clecoed the sending unit onto the tank access plate, and then inserted the arm to make sure it cleared everything.  I did have to bend it a little this way and that to get the float to work like I wanted but eventually after some gently bending I managed to get the float to rest just above the tank bottom, with it traveling all the way to the top almost touching the top skin.  Then I hooked up a Vans fuel level gauge I bought from another builder so I could make sure it worked OK.

Here’s a video of it working.  Forgive me, I shot this with my iPhone while I was trying to hold it and work the fuel sender as well.

After I tested the fuel sender, I called it a night.  Tammy had dinner cooking and it was making the whole house smell AMAZING, even down in the shop.  I was getting to hungry to push on any further for the night! But, this essentially finished up the actual fitting portion of the tanks.  I do still need to install the float sender in the left tank, but due to its flop tube, I will need to put the float sender on the baffle, and I may wait until I have some prosealing done before doing that work.

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Google Photos Link: https://photos.app.goo.gl/Zb3cMxNkRWSwhdjJ6

Hours Worked: 2.0

Right Tank Vent Line and Capacitive Senders

After a short break, I came back down to do some more work on the airplane. Tonight, I was able to get the right tank vent line and the right tank capacitive senders assembled and ready.  This time I cleco’d all the ribs and skin for the right tank in the stand so I could get some work done on it.  Once I had it all assembled, I grabed the 1/4″ soft aluminum tubing and began unrolling and straightening it to form my tank vent line.

Then fed the line through the holes in the tanks ribs until it was at the very end of the outboard outside rib.  I left about a foot extra on the inboard side, because I need to bend it a little to go to the fitting on the inboard outside rib, which I still need to drill the hole for.  Thats next up. So grabbed the inboard outside rib, and marked where I wanted to drill the hole for the vent line fitting.  We’re not given any specific spots, just a rough location where we should put it.  I made sure I had enough clearance to work around for the BNC connector for the capacitive senders, marked the hole and drilled a pilot hole with a #40 drill bit, then enlarged it to the proper size for the AN833-4D bulkhead fitting using my step drill bit. Once I had that done, I started bending the vent line so that it would meet up with the fitting nice and straight.  This took some trial and error and many times putting the rib on and off to get it just right. I also installed the modified / notched SB437-r bushings in the ribs.

But, after a bit of fiddling and work, I am very happy with the results.  I honestly like this better than my left tank, and I will probably go back and re-bend my left tanks vent line so it looks as nice as this one 🙂

Now that I had the vent line made up, I pulled it from the tank and put it in a safe place and continued on working.  I figured I could probably knock out the capacitive sender plates for this tank tonight too, especially since I had the tank already assembled.  So, just like the left tank, I inserted the plates to double check the orientation, marked it, and then removed the ribs so I could back drill them.   And just like the left tank I done earlier tonight, I measured the distance from the back of the rib (4.5″) and then used a 5/32″ center punch as a spacer to get the clearance on the top and bottom of the plates just right.  Then I clamped them down, and back drilled using a #20 bit into the ribs with the pre-punched T-813 sender plate as my guide.  I did this for both the ribs / plates in the right tank, as there are two plates. Recalling that we need to remove the plates, and then enlarge the holes in the RIBS ONLY to a 1/4″ hole as well.

Once I had both the inboard and outboard inner ribs and plates drilled.  I deburred all the edges and holes in the plates as well as the new holes in the ribs and then dimpled the proper side of the sender plates to accept the AN426AD3-3.5 rivets for the nutplates.  Once I had them dimpled, I clecoed on the nutplates and then squeezed the rivets, double checking that I had the nutplates on the correct side, as its VERY easy to get these wrong.

Recalling that the outboard most sender plate needs to be notched a bit to clear the stiffeners since it is mounted on the opposite side of the flanges.  I clecoed on the stiffeners, and then did a rough assembly of the T-813 sender plate and its plastic washers and spacers, to get an idea of where to notch. I marked on the plates where I needed to notch them, used some snips to cut the required pieces off  the one plate out so that it cleared nicely around the stiffeners per the plans.  Once I was happy with the fit, I took the plate over to the bench grinder to deburr the newly cut edges nice and smooth.

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Once I hand the edges trimmed and deburred, I clecoed on the nutplate for this outboard sender plate and squeezed the rivets to hold the nuteplates on, and did another test fit using the hardware to make sure it fit nice and perfect.

  

That pretty much completes the fabricating and fitting of the sender plates for both tanks.  I can’t really install them until I am close to sealing the tanks, so they will go in the parts stack for their respective tanks until I get ready to seal things up.  I went ahead and finsihed assembling the right tank in the stand, including cleco’ing on the access plate, and fuel pickup tube.  I will be installing the resistive senders in the next build session, so I wanted to get the tank ready for that step.

  

Thats all for tonight.  I am happy with the amount of work I got done tonight, and I’m in a good starting point for the next build session.  It’s getting close to sealing the tanks. I just need to finish up these last little bits of fitting, then I need to deburr and dimple and do final skin preperations for the parts before riveting.  The tanks do not get any primer, so we can skip that step at least!

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Google Photos Link: https://photos.app.goo.gl/zn7mZSEkp6px4gPs5

Hours Worked: 2.75

Left Tank Capacitive Sender

Getting to do some neat work on the fuel tanks now!  I started on the capacitive sender plates that I am planning on putting in the tanks.  These will be my primary means of fuel level indications, with the float style senders being a backup.  Yeap, I am installing both capacitive and float style senders, since they are both lightweight and easy to do with the tanks being assembled.  I read over the instructions several times, and looked over the plans and drawings to get an idea of how these go in.  They are pretty dead simple:  Two aluminum plates mounted on the ribs, and electrically isolated from the fuel tank with insulators “dip” into the fuel thats in the tank and measure its resistance / capacitance to get an idea of how much fuel is in the tanks.  The tank skins and ribs are the other side of the circuit, with the fuel being the conductor between the sender plates and the tank skin/ribs.  Dead simple system with no moving parts to wear out.  The only downside is that its calibrated to the fuel type, in my case 100LL.  If I ever decide to run a different fuel blend (mogas, 100LL, or whatever) I’d need to re-do the calibration which involved fueling to a known quantity and running the calibration program of the fuel sensor units.

The work starts off by fitting the pre-punched T-813 sender plates into the outboard most inner rib and measuring its clearance distance. We need it to be 4.5″ inches from the bottom of the rib, and it needs 5/32″ clearance between the rib flanges.  So, I measured it out, and used a 5/32″ center punch to get the measurements correct and clamped the plate down.

Once I had it clamped into place, the plans tell us to use a #20 drill and then back drill into the ribs for the screw holes using the T-813 plates as a guide.  Then it has us remove the plates, and then enlarge the holes in the ribs ONLY to 1/4″.  After that, we do the same exact process on the inboard most inner rib.  Once the holes were drilled, I deburred all the holes in the ribs, as well as the sender plates. The next step has us rivet the nutplates onto the sender plates, double checking the orientation is on the correct side of the sender plate.  After a study of the drawings, I riveted on the nutplates with my squeezer. Take note, the plans has us use AN426AD3-3.5 rivets, so I had to dimple one side of the sender plate to accept the head of the rivet.  I did this to both ribs / senders of the left tank.

Next up was to drill the hole in the inboard external rib for the BNC connector that goes to the sender plates.  Following the drawings, I positioned my marks roughly where the plans has us, and then double checked that my flop tube would not hit the wiring or the inside bits of the BNC connector, then drilled a #40 pilot hole, and opened the hole to the right size for the BNC using my step drill bit.  I went ahead and did this to the right tanks inboard rib as well, while I had the drill bit chucked up.

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The other hole you see in the pictures is where the fuel tank vent line goes, trust me its not a stray hole 🙂  I did a rough assembly of the parts to make sure everything was looking good in the tanks.  I notched the bottom of the sender plates as per the plans, but after I did the assembly, I don’t think i really needed to.

  

You can see how the plastic washers act as spacers and isolators for the sender plates.  There is also a plastic tube that I will cut to 15/32″ to that the screw goes into to fully insulate the screw from touching the ribs. Finally the plans has us cut some of the 18AWG wiring to 15″ lengths, strip one end and solder it into the BNC connector.  Once we install the BNC for good, we’ll be slathering this thing in plenty of proseal to not only seal it up, but also protect the soldered connection as a sort of strain relief too.  So, I took the wire up stairs in my office where my soldering station is, cut them to length and soldered them into the BNC’s.  I went ahead and did both the left and right tank BNC’s since I had the iron fired up. Here’s how they came out:

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Thats it for this build session.  Going to grab some dinner, and then I’ll probably come back down and start doing this work on the right fuel tank.  It should go alot quicker now that I know what I am doing.

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Google Photos Link: https://photos.app.goo.gl/fAy5jGWGLnEELWcV7

Hours Worked: 1.75

Left Tank Vent Line

Super short session tonight.  I came back in town from being on the road, and wanted to get something done on the build to keep the progress going.  I left off with the left tank clecoed back together so I can start working on the last bits and hardware,  and this session I decided to get the vent line cut and ready to go.  I pulled out the stock of 1/4″ soft aluminum tubing which came with the wings.  Vans sends 19 feet of it most of which goes for the pitot system, but I am going with a different system for pitot and AOA, so I will have PLENTY of extra to play with.  I uncurled enough tubing to give me about a foot extra of vent line for the left tank. Then straightened it out and feed it through the holes in the ribs.  I removed the inboard rib since I need to drill a hole for the fitting.

Next up was to locate and drill the hole for the elbow fitting.  This is the plans for the fitting, and the rough location of where to drill the hole for it.

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So, I made a mark in the rough location of where it shows in the plans, and then drilled a #30 pilot hole.  Then opened the hole up to the proper size for the AN833-4D bulkhead elbow with a stepped drill bit.

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Since I am going to install capacitive senders in my tanks, I needed to notch out the bushings that the vent tube slides into in order to make room for the wiring.  I used my chainsaw sharpening file to notch out the lips in the SB437-4 bushing.  To make sure, I fitted the bushings on the vent line and inserted the wiring checking there was enough clearance.

I need 5 of these for the ribs in each tank, so I went ahead and notched out 10 of them, which is enough for both tanks.  Then, I snapped five of the bushings into the ribs for the left tank after I had deburred the holes for them.  After that, I threaded the aluminum tubing into the ribs, through the bushings so that I could get it lined up and cut to length and flared.  I need to pick up a tubing cutter before I cut to final size. My tool kit came with a nice Parker flaring tool but not a cutter. heh.  So, I’ll order a tubing cutter this week and get it ones its way.  Heres where I ended up tonight:

Thats where I leave it for the night.  I’ll get a tubing cutter on the way, but I can start working on the capacitive senders while its being shipped.  I left my tubing a little long to give me some room for margin, and I also have some scrap tubing to practice cutting and flaring on before moving on to my “production” parts.

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Google Photos Link: https://photos.app.goo.gl/zYoputXmk6761L2H6

Hours Worked: 0.75