Making the Tank Stiffeners

Tammy and Acacia went on a “Girls Night” with my mom and sister to Knoxville, and they’ll be gone overnight, which freed me up to do some work on the RV-7 tonight.  The work for tonight started with making the tank stiffeners from the provided punched and notched stock.  These are the T-711 A through D stiffeners for each tank.  They were pretty easy to cut from the stock using a pair of snips and going along the notches to indicate where to cut.  This is similar to the stiffeners used in the control surfaces, so its very familiar work.

And here’s the pile of stiffeners, cut out and ready to take to the bench grinder for deburring:

I spent about 20 minutes or so on the bench grinder working these stiffeners on the scotchbrite wheel to deburr the edges and smooth out the cuts I made. They came out looking pretty nicely.  Since these are going inside the tank, they will NOT get any sort of primer or alodine.  I will clean them with acetone before I bond them with proseal and rivet though.  Next the plans tell us to cleco the stiffeners to the tanks, and match the drill the holes.  All of these are different sizes (A through D) but Vans offsets the rivet holes making it a simple task to find the right ones and get them in the right spots.

After I had those all match drilled, the next thing was to put the T-701 tank skins onto the baffle and check the fit on the wings. I did this a little differently, as I wanted to make sure I had all my holes lined up on my baffles.  I clecod the baffle to the T-701 skins and then mounted the assembly onto the wing checking alignment.  I then clecod the skin assembly to the main spar to make sure it was steady.

Then I reached in from the side, and marked the holes onto the tank attach brackets using the baffle as a guide after I made sure the centerlines from the tank attach brackets were showing in the center of the pre-punched holes in the baffles.  I marked as many holes as I could reach, and pulled the assembly off to check my alignment:

 

It’s not EXACT, but its very close! Once I was happy with the alignment, I clecoed the baffle back down to the tank attach brackets and then backdrilled into the brackets using the remaining holes in baffle as a guide.  I ONLY drilled the center hole in the brackets, leaving the other 4 holes for later, as prescribed by the plans.

Now that the baffle had enough holes to cleco it down to the attach brackets, it was time to start cleco’ing on the ribs!  Once the ribs are on, I will backdrill the ribs, baffle, and tank attach brackets together using the rib holes as guides.  I clecoed on the ribs, double checking their placement with the plans.

I was pretty spent after clecoing the ribs on, so I decided to call it a night, and do the backdrilling when I was fresh.  Of course, I did this same set of procedures on the other wing, I just simply showing photos from one wing in the blog post 🙂 . Heres all the photos from tonights work:

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Google Photos Link: https://photos.app.goo.gl/z1bQgQJa14SmSxr19

Hours Worked: 3.5

Tank Attach Brackets Part 2

WHAT? I’m actually getting something done on the RV-7?  Yep.  Thats right, I found some more time to work on the airplane tonight. This new position at work has been keeping me busy, but I think I am going to have more time to work on the airplane since I will be traveling a lot less.  I have been briefing up where I left off this past week, so I am not adding those hours into the build.  I need to get these tank attach brackets finished up so I can continue with the tanks.  So, I pulled the brackets off the wings so I can drill the nut plates and deburr them.  I marked the locations so I could get them exactly returned to where they came from, and then started on the nut plates.  I don’t have a nutplate jig, so I had to make do with my tools on hand.  I used an AN3 bolt to thread into the K1000-3 nutplates so I could line up the “ears” on the nutplates with the centerlines I had drawn on the brackets.  Then, while holding the nutplate in this position, I drilled one of the holes.  After the first hole was drilled, I stuck a cleco in to help hold it all squared up for the last hole to be back drilled.

I used some clamps to help hold the bracket on my table as I drilled. Eventually I turned this into an assembly line:

Once I had all 12 (6 on each side) of the tank attach brackets drilled for the nutplates I moved on to deburring all the holes, as well as all the corners and edges to make them nice and smooth.  On the front side of the nutplates, they are attached with AN426 flush rivets, so I needed to countersink the holes for a nice smooth fit on the side of the tank attach brackets that gets bolted to the main spar web.  I used my clamps again to hold the brackets to the table, and then fired up the micro-stop countersink and adjusted the depth so the rivets would sit nice and flush.

I again, turned this into an assembly line, by clamping several brackets to the table and doing the countersinks all in one run 🙂 Once I had all the countersink done, I decided to go ahead and Alodine these parts.  I’m not going to prime them, since a good Alodine coating will be plenty of protection.  I got my dunking tanks out and started the process. First up, cleaning them with Alumaprep 33:

Then after a quick rinse to rid then of the Alumaprep, I dunked the in the Alodine bath for about 10 minutes:

Heres a shot of me doing the work to prove I am the dude building the plane.  You might notice that I have lost a good bit of weight!  Nearly 83 pounds to date, all from eating 1800 calories per day and doing a ketogenic diet.  It feels pretty amazing, but this blog isn’t the place to discuss dieting, unless we are measuring the gain in useful load 🙂

Now that the parts are Alodined, i went ahead and riveted on the nutplates.  I clecoed one hole of the nutplate to hold it, while I used the Numatix rivet squeezer on the rivets.  This made quick easy work of them, and in not time, I had 12 tank attach brackets all ready to go!

The plans tells us to go ahead and bolt these onto the main spar web using the AN304 bolts, and a washer (the size escapes me currently, but I did find the correct size on the plans).  I am not sure why we bolt all three bolts for each bracket, as they’ll need to come off again to rivet them onto the baffle.  So, I just used two bolts per bracket and got them snugged up onto the spar web for alignment purposes in the next step,  These will be coming off in the near future when we seal up the tanks.  I’ll reinstall them with all the bolts and apply proper torque values and then some paint some torque seal on them.  Here’s how they look for now:

This was a long working session!  Even though it doesn’t look like much was done, there was a lot of work in those nutplates! From here I’ll fit the baffle and the tank skins.  Heres all the photos from tonight:

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Google Photos Link:  https://photos.app.goo.gl/ccsAmu7qk7K5dn8k6

Hours Worked: 4.75

Drilling The Tank Attach Z-Brackets

Time to drill the tank attach Z-brackets.  I swung by Ace and picked up some cheap 10-32 bolts, nuts and washers to temporarily hold the brackets to the spar for back drilling.  These will get tossed for the final assembly, they’re just used to help steady the bracket for precise drilling.  I actually had my little helper Acacia tonight for a little while.  We stuck a bolt, and washer in each bracket and then put them on the spars.

Then I squared up the brackets to the spare to make sure they were perfectly aligned.  My little helper gave up and got bored so she went back upstairs to play with her dolls.  But I managed fine on my own. HAH.  I used the cheap nuts and bolts in the center hole to tightly hold the bracket to the spar so they wouldn’t move when I was back drilling them form the other side of the spar.

I used a small square to make sure the brackets were lined up perfectly perpendicular with the spar.

Once I had all of the brackets installed and squared, I tightened the bolts down and then double checked them with my square to be sure they didn’t move.  I did the same to both spars.  Next up was to back drill the other two holes in the brackets by using the pre-punched holes in the spars as a guide.  Unfortunately, I didn’t snap a pic of the back drilling process, nor the final results.  I’ll get a photo of them in the next build log.

I wanted to make sure I had things correct before moving on to the next step, so I slipped the baffle onto the right tank skin and then placed the assembly onto the wing so I could check that the prepunched holes in the baffler were lining up with the centers of my tank attach brackets.  Heres the baffle installed on the skin, in my jig.

And here’s the assembly cleco’d onto the wing.  The alignment was really good, and the prepunched holes were lining up nicely on the center of the tank attach brackets.  Its starting to look like a real wing now!  Now, you can see the bulging in the skin where the fuel filler is.  That is because I do not have the internal ribs installed.  This was merely a test fit to see if the baffles lined up on the center of the tank attack brackets.   The tanks will come off before I do any more drilling 🙂

I was pretty happy with the results so far, and decided to call it a night.  I’ll take the tank assembly off in the next build log, remove the attach brackets and drill their nut plate holes.  Once I have all the nut plate holes drilled, I will probably prime them, and then install them onto the spar for the next steps.

Heres the Google Photos album: https://photos.app.goo.gl/8tAeECZ8mQ5VSsi36

And heres all the photos from the build session:

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Total Time spent: 2.75 hours

 

 

 

Drilling the Fuel Tank Z-Brackets

4 months?  Has it been that long since I last done any work on this thing?   Yep. It has.  I decided to mozy down to the shop to get a little work done on the plane tonight.  I have been busy with work, family and travel, and the Cardinal, that I just haven’t had any spare time to work on the build.  I got down to the shop and first had to do a little housekeeping as it had gotten cluttered over the 4 months.  I’m not counting that time in the build though.  After I got things organized into my “shop” again, I decided I’d pick up where I left off.  The Z-brackets.

In my last post, I also said I needed to place an order with Van’s to replace the messed up W-408 end ribs.  I am going to get that order placed tonight / tomorrow and also toss in the pro-seal and some other bits and bobs I need to complete the last little pieces of the leading edge and stall horn.  It won’t impede progress of the next step or the fuel tanks thank goodness.  I started off by doing lost of refresher reading, including some videos on Youtube and looking over Mike Bulloks post about them.  Folks seem to have the best results using the Checkoway method, which I was I did as well.  I measured 11/32″ from the outside edge of the web on the Z-bracket and made my centerline.  This lets the nut plates (the ones used to bolt the tank to the spar) get as close as possible to the web to give you more room on the opposite side of the web to pull the blind rivets that go into the baffle.

Once the centerline was done, Vans has us mark and drill the very center lengthwise for our first bolt hole.  My Z-brackets were 4.5″ long, so I marked my hole at 2.25″ using my square.

There are 7 brackets for each wing/tank.  We are only going to drill these 11/32″ holes in 6 from each side, as the inboard z-bracket is mounted a little different.  So, for now, I jigged these 12 brackets up in my drill press and drilled the holes with a #12 drill bit.  Coincidently, I noticed my drill quill also had a bit of wobble in it, so I spent probably a half hour trying to adjust it out.  I got it good enough for now, but not where I want it.   I’ll use this guide when I have some spare time: drill_press_tune-up

The holes came out good enough for me. These will get an AN3 bolt, and like Mike Bullock, I decided I will use a spare AN3 bolt, washer and nut to temporarily clamp them down on the spar and use a square to get them lined up perfect so I can back drill the other two holes in the Z-brackets.  BUT….of course I didn’t find any junk or spare bolts in my bins or garage to use, so I will hold that for another build session.  I did get all the 12 brackets center holes done though:

And that is where I’ll stop tonight.  I’ll run by Ace and get a couple of AN3 sized bolts, nuts and washers to use to hold these to the spar for back drilling.  I don’t want to use the “official” hardware for that.  I’ll save those for the real assembly.  I’m headed for Houston tomorrow (on Labor Day no less!) for work so it might be another week or so before I get back after it.

Google Photos Link: https://photos.app.goo.gl/ZLrsMNSYi8q7DLtL8

Hours worked: 2.25

 

 

Assembling the Right Leading Edge

Time to finish up the leading edges….almost.  You see, I realized I made a mistake and back drilled the W-408 ribs too close to the flange bend, and they’ll need replaced.  It happens :-/  But, I did manage to get the right leading edge mounted on the wing.  This is a repeat of the left wing, so I wont go into too much detail.  I started out by getting the leading edge skin mounted into the cradle so I could start clecoing the ribs in place. Then I stuck the ribs in, and clecoed them in starting from the leading edge and working my way back.

Once I had the leading edge assembled, it was time to mount it onto the spar and start the pain in the but….making the joint plate and back drilling the W-408 rib.  This is probably one of the worst parts about the wing build.  The W-408 isn’t pre-punched, so you have to get the joint plate, rib and skin all lined up just right and then back drill using the skin as a guide.  I messed up my edge distance on this one, as I will note late on in this post.

Now its time to make the joint plate.  Van’s has the dimensions in the plans for this strip, but I have found that they actually sent two pieces (one for each wing) that was already cut to the dimensions, which was nice:

I removed the plastic and marked a line 1/2″ from the edge per the instructions.  This line is used to line the joint plate up with the skin. After that, I marked the center of the flange on the W-408-1R rib that rivets to the spar.  This was so I could see where I should line up the rivet holes on the spar for match drilling. Then I slipped it into place with the leading edge, lined up the blue line with my spars rivet holes and match drilled them using a #30 bit. These holes turned out great:

Now the fun part.  Trying to form the joint plate into the shape of a leading edge.  I remove the W-408 rib that I had just drilled (in the photo above) so I could use it as a template for my initial hand-bending.  After a good while I sort of got it to resemble the shape of a leading edge. Then I re-clecoed the rib’s flange to the spar, and started working the joint plate into the small gap between the W-408 rib, and the skin.  After fiddling and tapping and fiddling and moving, etc I finally had the blue line I marked on the joint plate lining up with the holes in the skin.  I had thought that the plans said we’d need 11/16″ inch from the rib to the outside edge of the joint plate, so thats what I did:

I was obviously wrong.  I drilled all the holes using the skin as my guide and was thinking everything would be perfect, because I measured this thing a thousand times and has that 11/16″ perfect at each hole.  I was SO SURE this rib was lined up.  So I took the rib and joint plate out to check my work:

And there it is…. WAY TOOO CLOSE.  I thought to myself…”This is exactly the way I did the left rib, so let me make sure I didn’t mess it up too”. And sure enough, I messed it up too:

Oh well.  Thank goodness these are only about $28 bucks from Vans and I am still able to replace them.  It was at this point, I decided to call it quits for the night.  I still need to match drill the right leading edge, but I’ll leave that for another session.  The next step is the fuel tanks, so I need to place an order for some proseal, and other goodies, so I’ll toss in two new W-408 ribs to replace these ones.  I am thinking it may be easier next time to get this right, since the joint plate has its holes.  I can just mark the centerline on the new ribs, line them up the holes in the joint plate and skin and match drill.  The joint plates turned out pretty nice, and they even look like a leading edge:

Time to spend some money I guess.  I’ll probably order some sealant, conduit, new W-408 ribs, and see if I can find a good aviation grade crimper set.  My “mistakes” pile is growing 🙂  Thankfully its still much smaller than my pile of completed parts.

Google Photos Link: https://photos.app.goo.gl/wMDxjsoBsiXhjxBX9

Hours Worked: 2.75

Assembling the Stall Warner

I wanted to knock something out tonight since it’s been a while since I last worked on the plane.  So, I figured it was time to finish the stall warner.  I had alodined all the parts to it previously, to help prevent corrosion, but I did not get any photos.  Tonight, I finished building it, all except the electrical connections.  I need to order a good set of crimpers. The session started out by dimpling the nut plates.  I’ve read a bunch on the best way to do this, but theres really no good way.  They are gonna warp regardless.  So I dimpled them in my DRDT-2.

Sure enough, the warped.  But it a little tappy-tap-tap with a small hammer on the back rivet plate and they flattened right back out.

With that bit of detail worked out, I moved on to assembling all those tiny washers, nuts and bolts into an assembly.  This was a fiddly operation, but actually quite fun.  This is the sort of building I enjoy, and its a good break from the monotony of the wings.  The little switch is pretty straight forward, I just had to make sure I had the right washers and the right number of them in the correct spots as called out in the plans.  Then tightened  down the lock nuts just enough so that the actuator worked nice and free, but not sloppy.

It turned out pretty great!

I am not 100% done with it yet.  I still need to make up the 3″ pigtail for the electrical connector and crimp on the terminal, but I am going to wait until I get a good set of aviation grade crimpers to do the job.  Not my cheap, autozone jobbers.  So, I put this assembly away in a little tub, and decided to remove the plastic from the right leading edge, before calling it a night.

Thats it for tonight. Heres a  Google Photos Link: https://photos.app.goo.gl/KH9jBunbivXv7s3H7

Hours Worked: .75

Pre-assembling the Stall Warner

I decided to tackle some small things tonight – The stall warner.  I have been looking forward to this for a while now, because it looks a bit intricate (a nice break from the monotony of the wings!), and includes a little electrical work.  The first step was to open the parts bags and sort all the bits, pieces, nuts and bolts! There was a lot of tiny washers, and nuts to sort. Thankfully I was not missing anything, I did not inventory this kit when I received my wings.  Not sure why I didn’t, but I would recommend that you do.

The first thing I needed to do was deburr all the holes and edges in the inspection plate cover and its doubler.  I removed all the blue plastic, deburred the holes on each and then smoothed the edges down.  The plans tell us to go ahead and rivet the nut plates on now, but I think I am going to wait and do that AFTER I alodine all these parts together in a batch, so I set it aside for now.  Following that, I removed all the plastic from the small brackets and deburred the edges on the scotchbrite wheel for each one to make it easier to work with.  I also rounded the corners of the stall warner vane as per the plans.  I think its stainless? So it was a bit more difficult than the soft aluminum to work with a bastard file.

Then the plans tell us to double check the layout of the mounting bracket, and then machine countersink the holes where the three screws hold the stall warner switch , as well as the two AN426AD3-3.5 rivet holes that holds two nut plates.  I decided to do this by hand and just use the screws as my depth guide checking every now and then again until I had removed enough material for them to sit flush. Here’s how it came out:

Now comes the fiddly part.  I spent some time with the dial calipers measure the three different sizes of washers to make sure I had them correct, because on the smaller ones, there is only 1/16″ difference in thickness, something my eyes can’t see!  A cheap digital calipers worked great for this.  Now that I had my washers sorted, and my bolts and screws identified, I laid everything out and started assembling it:

Now that I had those spacers looking correct and the stall warner vane setup, I slide the switch itself on and stacked the other side of washers:

Then I laid on the retaining plate and made sure to use the thinner washers where appropriate:

I didn’t want to torque anything down, as I need to alodine the assembly, so I just finger tightened the nuts to make sure I had everything pre-assembled correctly. The whole assembly came together really nicely, and its a very simple and robust design.  It uses machine screws with hex heads going into nutplates to hold it to the leading edge assembly, so it should be easily removed from the leading edge via the inspection plate if maintenance is ever needed on it.   The entire assembly would slide right out, very clever!

Once I was happy I had all the parts in the proper places, I slowly disassembled the unit and made sure to remove the thinner washers (there’s only 4 of them) and put them in a separate and labeled container to save time on final assembly.  The rest, I stuck on the bolts and finger tightened the nuts on the bolts/screws to retain everything.  Then I set it all out on the bench for tomorrow.  I plan on dimpling and then alodining the aluminum parts tomorrow night, so they will have some decent corrosion protection. I may even spray them with some AKZO just to be safe, since they will get wet from the slot on the leading edge.  Heres a shot of all the parts laid out and somewhat organized 🙂

Google Photos Link: https://photos.app.goo.gl/1XQjmuetywXxaY5XA

Hours Worked: 1.5 Hours

Fitting the Left Leading Edge

It’s starting to look like a wing! Tonight, I decided to get the leading edge fit to the left wing to get an idea of what all was involved.  When I left off last time, the leading edge was loosely put together in the cradle, so thats where I started.  I first matched drilled all the holes for the stall warner access cover doubler and the stall warner mounting bracket (that goes in the leading edge) to the proper #40 hole, then removed it and put it on the bench.  I’ll do the assembly of it after I get the leading edge on the wing so I can have more working room.   I had a little helper helping with the stall warner:

Next up, was to get the leading edge on the wing, and clecoed into place, which went smoothly.  I clecoed all the ribs from the aft side of the main spar, and the clecoed the aft edges of the skin to the spar.  It fit really nicely, and its looking close to a wing!

Now, this is where it gets a bit…..fiddly.  The W-408-L wib is NOT pre-punched, so we have to back drill it using the skin and the spar as a guide.  In addition, we have to fit a W-723 joint plate sandwiched between the W-408-L rib and the leading edge skin.  Here’s the fiddly bit:  The W-723 joint plate is nothing more than a piece of AS3-032 sheet pre-cut to 1.5″x36.5″.  Which is nice, because its cut to the exact dimensions, but I had to bend and mold it into the shape of a leading edge. Before I went about bending it, the plans tell us to draw a line 1/2″ from one edge. This is the line we will use to help line the joint plate with the pre-punched holes in the skin.

The photos above, you can see where I have already drilled it, thats because I didn’t get any photos of me bending it. I will on the right wing 🙂 . But, once we had all these pieces sort jammed together on the leading edge, I double checked all the clearances, and then back drilled the aft flanges of the rib to the main spar, and clecoed it securely.  Next, I made sure my blue sharpie line was lined up correctly in the leading edge skin holes and then double checked the rib was straight with a square.

I started at the aft edge, and back drilled a #40 hole using the skins holes as a guide, then clecoed it.  I skipped a few holes and drilled another and clecoed to help make sure nothing was moving.  I kept doing this until I had everything back drilled.

Once I had everything back drilled, the only thing left to do on the leading edge was to match drill all the holes in it.  So, I chucked up a #40 reamer and reamed all the holes (ribs, spar, etc) to the proper size, then moved my clecos, and reamed those holes.  Eventually, I had all the holes reamed, but there were a few that needed back drilled at the front of the leading edge, so I used a #40 drill bit on those, and marked them so I would remember to deburr them. That finished up this session, and I think I will work on assembling the stall warner completely, getting it test mounted, and then open up the hole in the leading edge skin for the tiedown. Here’s all the photo from tonights work:

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Google Photos Link: https://photos.app.goo.gl/zxEU6f3vWHnQctkE6

Hours Worked: 2.25 Hours

Assembling the Left Leading edge and Stall Warner

I started out tonight assembly by doing some disassembly! I needed to remove the right wings bottom skin per the plans (both bottom skins come off, the left I did last night), and to free up some much needed 3/32″ clecos. I was running pretty low!  This was quick work, I removed both the inboard and outboard bottom skins and tucked them safely out of the way for now.

The next step was to build the leading edge cradle, to make assembling the leading edge and tanks much easier.  I built them pretty much to Vans specs, and used a W-709 leading edge rib as a template for where to cut:

I only traced the line onto one of the cradle supports, they are both the same size.  So, I screwed them together in a sandwich,  so that I’d only need to make one cut on the band saw and they’d be cut exactly the same.  I always say….even though I’m building a metal airplane, I tend to use my woodworking tools a good bit during this build 🙂   The band saw made quick work of the curvy cut, and the rib fits nicely in place, with enough room to put some duct tape or foam for cushioning and to keep from scratching the skin.

Then I cut a 2×6 to 26″ in length and screwed the cradle supports into it using some 3″ construction screws (yeah, a bit overboard on the 3″ but they were some I had laying around extra).  I’m pretty happy with the way they turned out.  After the photo below, I put some duct tape on the inside edges of the cradle to protect the skins a bit. I’ll make the second cradle once I need it, which will probably be the tanks.

Reading the instructions, Vans has us remove the plastic from the inside of the W-701-L wing skin, and put it in the newly made cradle to make assembling the ribs a bit easier.  It’s starting to feel like I am actually building again 🙂

Once I got the plastic removed from the inside of the skin, and put into the cradle, I cleco’ed the ribs into place to help form the leading edge.  A few of these were a bit tight, as I had to sort of bend the skin over a bit to get it to take shape against the leading edge ribs. I did the outermost ribs first, and then worked my way inwards clecoing every other hole.

The next step in the plans tells us to start working on the stall warner kit. This is where the plans gets a little hard to follow, as the RV-7 plans tell us to complete OP46-02 Steps 1-4 and OP46-03 Steps 1-5. These are actually provided in the stall warner sub-kit, which was designed to be installed in all of the different RV models, both during and after construction (in case of a retro-fit on an already-built airplane).

Stall Warner installation kit

Stall Warner installation kit parts on display

I had to read over the entire set of OP46 plans and instructions to get an idea as to what to do, and when to do it . There’s a few pieces of the kit we don’t need since the RV-7’s are now shipping with the holes already drilled for the stall warner. I didn’t need the template and the mounting bracket for the RV-9, so I put them in the scrap bucket.  The first step in mounting the stall warner, is to attach the access hole doubler.  Since my kit was pre-punched after Vans released this kit, the inspection hole was already cut and drilled, I just needed to cleco the doubler on for match drilling.

I double checked that the inspection cover plate fit nicely. Once these are match drilled, it’s time to do a little metal working.  The stall warner pokes out a small slot on the leading edge of the wing. Vans has pre-punched two holes where it needs to go, but they are drilled to a #40 size, and are used as placement holes.  I have to drill these holes to a #10 size, and then remove the metal between the holes to form the slot for the stall warner to protrude from.  Here is where I started drilling the holes and widening the slot.

I used a sharpie to darken the area between the holes to mark where I’d need to file the metal out.  Then I used a small file (a chain saw tooth sharpener to be exact!) to stick in the holes, and file the area out, very slowly sand methodically.  Once I had the hole widened enough, I used a small bastard file to flaten the slot and get a nice finish.  It’s not exactly perfect, but it should work fine, and probably won’t even be able to tell its not a perfectly straight slot 🙂

Lastly, I cleco’ed the VA-195F stall warner mounting bracket to the leading edge skin to check its fit, and alignment with the slot.  It fits decent, but I’ll need to do a little flange bending to get it perfect.  Not a biggie, and it’s expected with these formed parts.

My wife hollered down to the shop/basement that dinner was ready…so I washed up, put the tools away and headed up stairs.  It’s hard to turn down her delicious pot roast 🙂  All in all, I am happy to be building like this again, these parts are fun to work on because you get to see finished progress at the end of the build session.  Not to mention, the parts are different from what I spend the last 150 hours working on.  In the next build, I’ll match drill the stall warner parts, dimple the inspection doubler and probably alodine them, so they are ready for the nutplates. I may even build the warner switch assembly.  Here’s all the photos from tonights build session:

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    IMG_20190218_221540
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    IMG_20190218_221528
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    IMG_20190218_213941
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    IMG_20190218_212842
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    IMG_20190218_212837
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    IMG_20190218_212833
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    IMG_20190218_212826
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    IMG_20190218_204041
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    IMG_20190218_203804
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    IMG_20190218_200620
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    IMG_20190218_194455
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    IMG_20190218_193009
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    IMG_20190218_193004
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    IMG_20190218_190116
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    IMG_20190218_190106

Google Photos Link: https://photos.app.goo.gl/sEfZjQdvnQUzUz3z8

Hours Worked: 3.25

Match Drilling the Right Wing Skins

Tonight was pretty much the same as last night.  I wanted to get the right wing skins match drilled so I can move on to something a little less repetitive.  Just like the left wing, I match drilled the top skins moved the clecos and then reamed those holes.  I had to remove the bottom skin from the left wing so I would have some cleco’s left to work with, so while I had the bottom skins off both wings, I went ahead and torqued the tie-down mounts to the proper value and applied some torque seal.

I had to read up in Section 5.20 of the plans to see that the AN3 bolt and locking nut calls for 28 inch-pounds of torque.  I used my beam wrench to find the drag of the nylon nut to be about 5 in/lbs, so I added that to the spec’ed value to come up with a final value of about 33 inch-lbs.  I then snugged all the nuts down to the required 33 inch-lbs and layered on some torque-seal (Cross-Check brand) so I’d know if they ever back off.  I did both the left and right wings, on both sides of the bolts.

I know there are guys out there that make this stuff look so nice and neat when they apply it.  I can never get it that neat! But, I guess it’ll do its job of telling me when the bolt looses torque. Then I cleco’d on the bottom skin for the right wing and reamed the holes to the proper size, moved all the clecos down a hole (actually my wife helped me to that!) and then reamed those holes.  The wing skins are now match drilled; Left and right wings, top and bottom!

Reading in the plans shows its time to start working on the leading edge! I need to fabricate a leading edge cradle, that gets used to help hold the leading edge skins, as well as the tank skins when you are working on them. The plan only calls for one, but I am going to make two because they will come in handy when I am working on the tanks. I rummaged through scrap wood pile in the garage and came up with some plywood that I decided to use.  Here is how the plans calls us to build the cradle

So I cut up a few boards and called it a night.  I’ll finish the cradle tomorrow night and start on the leading edges!

I also did a live stream, but the audio was pretty horrible.  At least it will show that I am the guy doing all the work 🙂

Google Photos Link: https://photos.app.goo.gl/xkH4oGExJmB13H64A

Hours Worked: 3.25 hours