Trimming the Stiffeners for the Elevators

I started work on the elevators tonight.  I have the rudder parts ready for priming, so I tucked it away on the shelf to get the elevator to the priming stage then I will do them together to save time.  Like the rudder, the elevators use stiffeners that have to be cut and shaped from stock aluminum angle and then back riveted to the skins.  Van’s has done a great job on pre-punching the aluminum angle stock that you use for the stiffeners and they even include punch marks to show where to trim each stiffener.

There really isn’t much to discuss on creating stiffeners, you simple use the aircraft snips and trim the angle at the marks and then round off all the corners with a file.  There are quite a few of these buggers, but they go pretty quickly.  Once you have them trimmed out of the stock, we have trim an angle down to the trailing edge to make room for the narrowing gap where the skins for the trailing edge.  This is marked, so I just connected the punch marks with a sharpie line, and trimmed it out with my snips.

Then we snip down the leading edge of the stiffener for a bit of clearance, but not as a drastic a cut as the trailing edges.  The photo above shows a finished stiffener.  Once they are all trimmed out, I ran each one across the scotchbrite wheel to clean up all the edges and they are ready to be dimpled and riveted on to the skins.

Thats about it for tonight,  these things took me about 3 hours to trim out, shape, and clean up.  But, both sides are done and ready to be match drilled, then dimpled, then riveted onto both skins.  Thats work for another session!

Here’s the photos from tonights work:

Google Photos link:

Hours Worked: 3

Metal Prep on Rudder Pieces

Tammy and Acacia headed out to do some grocery shopping so I stayed at home and decided to work a little on the airplane tonight.  I only spent about 1.5 hours on it, but I ended up finishing all of the metal prep on the rudder parts.

I started out by deburring all of the holes in the remaining pieces.  I picked up a small little electric screwdriver which made the mundane process of deburring, really easy and quick.  I switched out the normal deburring cutter with the single fluted deburring tool when I worked on the thin skins.  I was also very careful on the .020″ skin to keep it from knife edging. I also removed some more strips of the protective plastic on the rudder skins, so that all of my holes are now clear of it.

Next up was to deburr the edges.  I fired up the scotchbrite wheel and ran all of the parts across it to smooth out their edges.  For the thicker rudder horn, I first worked it against the normal stone grinding wheel on the bench grinder, then smoothed it out on the scotchbrite wheel.   I then used my handheld deburring tool to smooth out the edges of some of the larger holes, and finished off the hard to reach edges with a scotchbrite pad.  I then rounded the corners of the skins, and hit their edges with the scotchbrite pad.

Not many photos since this is pretty simple work, but here is all the parts after they were done:

Hours Worked: 1.5

Fitting the Rudder Counterweight and Beginning Metal Prep

I only spent about an hour on the project tonight.  All I have left on the rudder is to fit the counterweight and then start the process of deburring, dimpling, and edge finishing so I can get the parts ready for priming.  I am seriously considering building an air tight spray booth in the basement that ventilates the air outside so that I can spray the parts regardless of time of day or weather outside.  Thats a project for another day though.

Tonight I began with drilling the forward hole for the counterweight into the R-912 rib.  I placed the E-614-020 lead weight in the rib and match drilled the hole.  The plans calls for a #10, but after getting the screw and nut called for in the plans, I think a #12 bit will work just fine.  I do however have a#10 dimple die set. I drilled a #12, and then dimpled the rib using the DRDT-2.  I also had a #10 countersink, so I used that in my hand deburring tool to machine countersink the lead weight.

The rear hole was back drilled into the rib using the pre-drilled holes in the lead weight as a guide.  Once I had that finished, I decided to work on preparing all the parts of the rudder.

Metal prep is something that you will spend A LOT of time on during a build.  I am going to pick up an electric screwdriver to hold the deburring cutter so I don’t kill my wrists using the little wobbly-spinning screwdriver tool. There are thousands of holes in the plane that need deburring. There really isn’t much to photograph or even talk about during these types of phases in the projects.  I started out by deburring a few pieces  of the rudder, and then decided it was time to call it a night.  I will pick up an electric screwdriver on Monday and make this work go a lot faster.  I knocked a few pieces of deburring out:

Heres the photos from tonights short build session:

Google Photos Link:

Hours Worked: 1

Assembling and Drilling the Rudder

Tammy and Acacia were out of the house for the night, so I made the executive decision to go ahead and rivet on the stiffeners to the skins without priming them now.  I will prime them with the rest of the parts later on, so that means there will be a small section of metal that is not primed, between the stiffener and skin, but it is alclad so I am not too worried about it.

I started out by dimpling both the stiffeners and the skins using the DRDT-2. The thin .016 skin dimples incredibly easy, so I was ginger with the force. Then I back riveted the stiffeners onto the skins, being sure I kept the work on the back rivet plate.  I wished I could back rivet the whole plane! The rivets came out looking perfect.


I had previously built the rudder skeleton, so the next step was to cleco on the skins to the skeleton and then match drill all the remaining holes, including the trailing edge wedge.  I cleco’ed every other hole so I could drill perfectly aligned, and then moved the clecos to their neighbor hole and drilled where they were.

Now that the rudder is assembled, the plans has us fit the R-710 rudder brace and then back drill it to the skins lower holes.  First we have to trim away a little excess on the part, as noted in the plans. There are notches and holes that can be used as a reference to trim, but after reading from several other builders, I opted to trim on the outside of these lines to give myself some extra metal in case I have edge clearance issues.  Other builders noted that if you cut along the notches, you an run into edge clearance issues after you drill the holes.  

The above photo gives a better idea of what I am talking about.  The bottom line in the line Van’s has you trim, where I opted to give a little extra as you can see from the top line I drew.  Thats the line I trimmed along and it worked out really nicely.

I have plenty of edge distance for all the holes, and I will just file down the edges to make them smooth and get rid of that notches when I deburr and edge dress all the parts.  I then clecoed this part to the skeleton so I could complete the next small bit of fabrication.  Next up is to fabricate the R-918 rudder bottom attachment strips.  These are strips of .032 that gets riveted onto the bottom of the skeleton to provide a flange for the fiberglass bottom cap to attach to.  Van’s ships about 40″ of .032 that is already cut to the 1 1/8″ width, so all I had to do was cut them to 18″ long and then trim out the little notch as noted in the plans, which as easy enough to do.

Once you have both sides fabricated, we use cleco side clamps to hold them flush along the bottom of the rudder, onto R-904 rib.  Then, back drill each one using the holes in the skin as a guide.

I was careful that I didn’t run into edge edge distance issues and used a Sharpie to mark the holes and check they were not to close to the edge.  Once I was happy, I drilled them.  I completed both sides of the R-918 and decided that after 6 hours of working on the rudder today, I’d call it a night.

Heres all the photos from tonights work:

Google Photos link:

Hours Worked: 6

Assembling the Rudder Skeleton

After a short break, I started on the second work session for tonight.  I had finished up the rudder stiffeners prior, and now its time to construct the rudder skeleton.  The assembly starts off by clecoing R-904 rib to the spar R-902.  Once its clecoed, we need to wide the hole in R-904 to a 3/8″ hole to match the hole in the spar.  This is where a hinge bolt goes in the future. I used a step-bit (Uni-bit) to widen the hole, which worked nicely.

Next I fabricated the R-917 shim from some of the scrap aluminum that Vans ships with the kit.  There isn’t many parts you have to fabricate, but this one is pretty simple. The plans includes a full scale template of the part.  After I had it cut to shape, I rounded the corners and dressed all the edges smooth.

Now that we have the shim made up, we can cleco on the rudder horn and being match drilling everything into place.  The rudder horn required a bit of grinding to get it to fit snuggly inside the R-904 rib, which is called for in the plans.  I used my bench grinder to get a rough shape that would clear, and then worked the edges down using a file.  Once I had the edges rounded, I smoothed it all out on the scotchbrite wheel.  It’s sooth as silk and fits perfect, even though this took quite a bit of time.

I clecoed on the R-606PP, R-902 spar, R-917 shim, R-904 rib and finally the R-405PD rudder horn to the bottom of the spar. I also went ahead and clecod on the other two doublers, R-607PP and R-608PP.  I then match drilled them all using a #30 bit.

I then moved on to fluting and straightening the R-903 tip rib and the R-912 counterbalance ribs.  These parts have some pretty aggressive curves punched into them, so they needed quite a bit of work to get perfectly straight and square.  I used a metal rule to check that the holes were all lined up.  Then I clecoed them both onto the R-902 spar, and match drilled them to the spar with a #30.

This is where the lead counterbalance will go, and there is a .032″ thick piece of skin that wraps around them to form the counterbalance.  The plans has us mount that skin and then match drill everything to a #40.  This took a little bit of work and fiddling to get the thick skin to mold around the ribs just right to line up the holes, but eventually I got it clecoed on.  Then match drilled all the holes to a #40 as called out in the plans.

This was a good point to stop, as the next steps in the plans has us clecoing on the rudder skins, which I do not have ready yet.  I still need to prime them.

Here’s the photos from this work session:

Google Photo Album link:

Hours Worked: 3

Finishing the Rudder Stiffeners

Tonight I finished up the rudder stiffeners.  I filed down all the corners and smoothed the edges down.  After that I ran them over the scotchbrite wheel to get the edges completely smooth and burr free.  Once I had the edges and corners took care of, I moved on to deburring the holes.  I finished all 16 stiffeners, 8 for each rudder skin, tonight and put them on the shelf until I can prime them.

After that I removed the protective plastic from the inside of the rudder skins, and then a few strips along the outside where the stiffeners will get riveted. I’ll leave the majority of the plastic on the outside surface to protect the skins until painting, sometime down the road.  I’ll prime the interior side in a few days.

Once I had the plastic removed, the skins are ready to be deburred and dimpled, along with the stiffeners.  I’m holding off on the dimpling until I get the skins and stiffeners primered, then I’ll deburr and dimple.  The skins went back on the shelf until priming time, and that was it for this session. Here’s the photos from this session:

Google Photos Link:

Hours Worked: 2.5

Fitting the Stiffeners to the Rudder

I started on the sections of the plans labeled “Building the Rudder” and more specifically, the sub-section “Fitting the Stiffeners to the Rudder”. The rudder is made of thin .016″ aluminum, so Vans uses tiny L-shaped brackets called stiffeners to help support the skin, and keep it from wobbling.  In the kit, these are parts that you have to fabricate a little.  The kit ships with 8 pieces of L-shaped aluminum that you have to trim into the shape of a stiffener.  The plans has the dimensions, and there are some notches in the stock to help you align your cuts.  I used my bandsaw with a metal cutting blade to make the cuts instead of using snips. Here is what the stock looks like:

And here is what it looks like after you rough cut the two stiffeners from one piece of stock:

After we have the stiffeners cut from the stock, we have to trim 7 out of the 8 per side to fit the rudder because it gets smaller towards the top.  In the RV-7, Vans has made this really simple: You cleco on the stiffener and then mark the hole on the forward edge that is the closest to the spar, and then trim off the excess.  It’s important to note in the plans, that we need to leave a 1/4″ edge distance from that hole which I did.  I then used the non-trimmed stiffener as a template to mark the cuts for the end angles.  Repeat this until you get 16 stiffeners and you are good to go!

Next up was to cleco the stiffeners to the skin to match drill.  I started with the left side, marked my stiffeners and skin and then match drilled them right down into a sacrificial piece of particle board to hold everything secure. I did the same to the right side.

After everything is match drilled, I disassembled everything so I could prep the edges and debur the holes.  This is going to take some time, so I only started on the left side stiffeners.  I was able to round off all the corners of the stiffeners, as well as knock down some really rough edges.  All 8 of the left stiffeners are ready for deburring, and then a trip on the scotchbrite wheel to smooth them out.  But, thats work for another session, I have already put in 4 hours tonight cutting out the stiffeners.

Here is all the photos from tonights work:

And the link to the Google Photos:

Hours Worked: 4

Assembling and Riveting the Vertical Stabilizer

Tonight I worked about 4 hours and completed the Vertical Stabilizer, except for the rear spar, which I am leaving off until the EAA Tech Counselor can come by and take a look at my work.  This will give them access to view and check my riveting and assemblies.  Once they sign off, I will rivet on the rear spar to both the Vertical and Horizontal stabilizers.

I started off tonight by assembling the skeleton for the vertical stab but clecoing VS-704, VS-705, VS-706 and VS-707 ribs to the front spar, and making sure everything still aligns correctly.  I temporarily attached the rear spar to double check, and then remove it to continue on. Then I riveted on VS-706 and VS-707 using AN470AD4-4 universal head rivets. I used my squeezer on them to set them perfectly.  BUT, VS-704 and VS-705 end ribs were a COMPLETE pain in the butt! The plans calls for a AN470AD4-5 rivet to hold these two ribs with the VS-703 front spar sandwiched between them.  The rivet was a little long, but I trusted the plans.  I could not get my squeezer in there so I had to buck them.  However, I could not use a standard AN470 rivet set, because the ribs did not have any clearance even if I flexed them out of the way.  I had to use an offset head, and ended up folding a couple rivets over.  After drilling out a couple of rivets, I FINALLY was able to get all three of these buggers set correctly.  After reading on Vans Airforce, a lot of builders have trouble with these suckers, so I’m not alone 🙂  Heres what the skeleton looks like after it was all riveted:

Once the skeleton was done, it was time to cleco on the skin and make sure it was lining up correctly.  This was about the time I realized I hadn’t dimpled the skin yet…whoops. heh.  So, I rolled the DRDT-2 over to the bench and spent the next 15 or 30 minutes dimpling the skin. Before dimpling, I made sure to tape up the holes along the root that are marked in the plans for nut plates to hold the fiberglass fairing in the future.

NOW, I can finally cleco the skin to the skeleton and get it ready for final riveting. I clecoed every hole on both sides because this is a large surface with some complex curves around the leading edge.  I figure a little extra work of clecoing will pay off when the results are smooth and oil-can free. After the skin was clecoed fully on both sides I begin to rivet it down. The plans has us start out at the intersection of rib VS-707 and work towards the top along VS-702 front spar.  This first rivet is a little longer due to the converging ribs, but thats the only one.  All the others were a AN426AD3-3.5.  After working up the spar to the top, I came back and worked toward the root along the front spar, alternating to the VS-707 center rib.  This is to get the skin down flush and prevent pillowing or oil-canning.  Once all the rivets were driven along the ribs, it was time to squeeze the ones along the end ribs.  I started on VS-706 and the leading edge and worked toward the trailing edge, and did the same thing with the VS-704 and VS-705 root ribs.  Once I had the left side done, I flipped it over and did the same to the right side. I am happy with the results! There’s no dents, dimpling, smiley’s or oil canning. This thing will paint up nicely along with the horizontal stabilizer.  If I can keep this quality of work up, I might end up with a decent looking airplane!

After I got it all riveted up, I temporarily clecoed on the rear spar so I can hang it on the wall to keep it out of the way and safe.  I am going to round up an EAA Tech Counselor tomorrow and see if they can come out and inspect them.  Here’s all the photos from tonights work:

And of course the Google Photos album link:

Hours Worked: 4

Riveting the Vertical Stabilizer Rear Spar

I worked about 2 hours tonight on the vertical stabilizer rear spar. I also spent a few minutes coming up with a way to mount my horizontal stabilizer on the wall to keep it safe and out of the way.  For about 2 bucks in hardware, here’s what I came up with:


And it actually looks pretty decent against the wall.  At the very least, I will have some nice looking aviation related wall art 🙂


After that, I continued on to working on the Vertical stabilizer.  Vans has us start on the rear spar of the vertical stab by clecoing on the Vs-803PP spar to the VS-808PP doubler, as well as the hinges VS-410PP, VS-411PP and VS-412PP.  I also taped off the holes where the VS-704, VS-706 and VS-707 ribs would rivet on later, so I didn’t accidentally rivet those holes.  img_0843

Once I had everything clecoed in place, and taped up, I was ready to rivet.  The plans have a myriad of different rivet lengths due to the thickness of the doubler, and the hinge plates so I started out by riveting on the VS-412 hinges at the top of the spar.  Once I had those on, I moved to the shortest rivet size group and worked my way up to the longest.  Eventually I had all the universal head rivets squeezed with my squeezer, and I could finish up with the bottom section of the spar.  This section I previously dimpled and countersunk because we need to use flush rivets on the face so that the spar will sit flush on the fuselage when we mount it.  So, I put my flush set in my squeezer, set the depth and set all those flush rivets on the bottom, finishing up my vertical stabilizer rear spar.  It came out looking really nicely!


Here are all the photos from tonights work:

And here is the Google photos link:

Hours Worked: 2

Finishing the Horizontal Stabilizer Skin

I was able to finish up riveting on the skins of both sides of the horizontal stabilizer.  I had only planned to rivet on the right side skin to HS-702 front spar and HS-708 rib, but that only took about a half hour to complete.  So, I decided I should continue on!  Here is how the riveting turned out on the spar and rib:

I was relieved to have finished off all the rivets that needed to be set using a rivet gun and bucking bar.  I am very happy that the skins turned out looking perfect and I didn’t dish or dent the skins.  These are going to paint up really nicely, and hopefully be show quality!

After getting the skins done, I continued on to riveting on the HS-706 end ribs and HS-00005 and HS-00006 end ribs on both sides.  These pieces are all done using a squeezer, so I wasn’t worried about them getting messed up or taking a long time to do.  Once you get the squeezer set to the right depth, every single rivet turns out the same, making for very pretty work.   I started out on the HS-706 end ribs, since they were easy to access. I worked them from the leading edge to the trailing edge to prevent oil-canning.  They turned out great, without needing any re-work:

img_0829 img_0830

Then I turned to the inner HS-00005 and HS-0005 ribs.  Like I did with the HS-706, I started from the leading edge and worked my way back to the trailing edge.  They also turned out really nice.  Once I had both sides done, on top and bottom, I decided to call it a night. I will leave the rear spar off until I can get the EAA Tech Counselor to come out and take a look.  With the rear spar off, they can peak down into the horizontal stabilizer and verify all my rivets look OK.  Once they have signed off on my work, I will rivet on the rear spar using the squeezer.

Here are all the photos from tonights work:

And here is a link to the Google Photos page for tonight:

Hours Worked: 1.75