Tag Archives: riveting

Elevator skin fitting

Hours: 3

First order of business for the Elevator skin was inspecting all edges and holes and there were a few edges that needed some deburring action.
Elevator skin edges needed some filing to remove the burrs

After deburring everything that needed attention, we wrapped the skins around the rib structure. Since the Elevator is a pretty big part, it was very helpful to have a second pair of hands for this.

The last thing I had to do before I can start on closing up the skin is to install the backing plate for the Trim motor inspection plate. The plans call for 1/8 rivets, but the holes were actually 3/32, so I had to first up-drill them. There’s also another small error in the plan, in that it says to rivet all 8 holes, but actually only 7 should be riveted, since the top hole is for the screw that holds the inspection plate in place.
Backing plate goes under the skin Holes are 3/32, so I needed to up-drill them to fit the 1/8 rivets Holes up-drilled and backing plate clecoed in place Quick test fit of the inspection plate

Elevator structure

Hours: 5.25

Time to finish off the Empennage and get the Elevator structure going. I received the replacement ribs that are bent just that little bit more in order to properly align with the reinforcement plates and skins and went to work to drill out the bad ribs and put in the replacements.

New ribs in place and a final picture of a few rivets that people that visited helped pull

After that, I went to work and torqued the bolts that connect the control rod and counterweight to the Elevator. There’s also a small support bracket that reinforces the center rib to spar attachment, which is a pretty tight fit, so I had to get out the manual hand riveter.
Torquing the AN bolts Bolts torqued and support plate riveted

My brother is currently visiting and is enjoying the riveting experience.
My brother enjoying the riveting experience

Once the center ribs were finished, we moved on to put the rest of the rib structure in place.Elevator rib structure finished Clecoing the ribs in place

After that I realized there’s a mistake in the plans as they instruct to rivet the edges that hold some of the side counterweights on, but there’s another small end rib that actually has to go on there as I found out after I checked the overall plan for the Elevator. Quickly drilled out the rivets and riveted on the part. A nice trick I learned from another builder for drilling out the rivets without damaging the holes they go through, is to only drill out the top of the rivet (the donut ring) and then use the center punch to push out the back of the rivet. This way you have less chance of enlarging the hole.
Error in the plan says to just rivet the endcap, but actually this part needs to be riveted onto the side End rib where it should go Holes drilled out and end rib ready to rivet

With the rib structure in place, time to work on fitting the skin.

Finishing the Flaps

Hours: 6

With the ribs for the Flaps out of the way, I am ready to finish the flaps. First order of business is to ensure that I have the ribs all in the right order.
Completed ribs laid out along the right Flap

Once that was figured out, I first clecoed the ribs in place to the bottom of the skins and then closed up the skins and clecoed the top as well.
Ribs clecoed in place to the bottom of the Flaps skin Clecos in place to close up the right Flap

After checking that everything is aligning properly with the skins, I started riveting the skin. The top side is pretty straightforward. For the bottom side, there are a couple of tight spots next to the hinges, so the close quarter rivet wedge came in handy for a couple of the rivets.

Rivets in place Close quarter rivet wedge to rivet the tight space next to the hinge Bottom right side Flap ready to rivet Bottom right side flap almost done riveting

With the right side Flap finished and closed up, I then repeated it all for the left side Flap. There was also a couple of the edges where the hinges sit that needed a bit of deburring attention.
Some deburring was needed for the hole where the hinges go through Upside down view of the left side Flap ribs clecoed in place Almost done with the left side Flap riveting

After I finished the top skins, I did one quick alignment test fit on the wings and everything looked good, so then I finished up both sides by riveting the front rivet lane that closes the skin against the other side.
Front line ready to close up the skins of the Flaps for good Almost done riveting the Flaps Completed left Flap Both Flaps completed

Final alignment check

Once I finished all the riveting, I did one final test fit onto the wings. I used a bit of mason string and my laser level and everything is looking good. Now onto finishing the Elevator.
Final test fitting and alignment checks Final test fitting and alignment checks

Timelapse of building the Flaps

Getting started with riveting the Flaps

Hours: 2.5

With the priming of the Flaps ribs out of the way, I got started riveting the Flaps. First order of business was laying out all the ribs in the correct order.
Flaps ribs laid out in the correct order

After laying out the ribs in the correct order, I started laying out the right hinges to go with each rib. There is one interesting rib that needs to be riveted in two steps as one part goes on top of the other:
Hinge and bracket to be riveted onto the rib Ready to rivet those 3 rivets that will hide under the angled bracket Ready to rivet the bracket on top of the hinge

Once I figured all of that out of the right side Flaps, I repeated the steps for the left side Flaps:
Right side ribs done and laying out the left side

I received the missing rivets for the assembly the other day, so now I was able to finish the riveting all of the hinges to the ribs to actually complete the flaps.Completed ribs laid out along the right Flap

 

Vertical Stabilizer skin riveting

Hours: 3.5

With the wiring finished and the Antenna fitting done, I am now finally able to close up the Vertical Stabilizer and rivet the skin.

To begin, I closed up the left side of the skin and held it in place with clecos, since this is the side where the Antenna slides through the enlarged rivet hole, while on the right side I had to create the custom notch so that I can pull the skin around the Antenna.
Left side of the Vertical Stabilizer closed up with clecos

Once that was done, I riveted on the support plate for the Antenna onto the top rib of the Vertical Stabilizer.
Riveting the Antenna support plate in place Antenna support plate riveted in place 

Now that the structure is complete, time to mount the Antenna permanently in place. Using two 20mm long M4 screws, washers and Nyloc nuts and some medium strength threadlocker I mounted the Antenna in place. Here’s the Antenna mounted in place and the wire connected to the Antenna using the BNC connector I crimped onto the wire. Antenna ready to be mounted Antenna mounted and wire connected

Riveting the skin

With all the prep work finished, I closed up the right side of the skin, made sure everything fits correctly and clecoed it in place. There are two holes on the bottom on each side that are not riveted, but instead I have to install Rivnuts in them, so I marked out those holes, so I don’t accidentally rivet them.
Vertical Stabilizer skin closed up and ready for riveting Holes where I have to install Rivnuts marked

There were two rivets that I had to shorten in order for them to fit flush near the Antenna. So I made a small template for the dept through a piece of wood and then shortened them accordingly.
Wood piece to hold the rivet in place to shorten Rivets shortened (and normal length on the left for reference)

After that, it was just a matter of pulling the many rivets on both sides of the skin to close the Vertical Stabilizer up for good.
Riveting the right side in progress Riveting the left side in progress Riveting the left side in progress Done riveting the skins of the Vertical Stabilizer

The last part was to install the two rivnuts on the bottom on each side, so after enlarging the holes using my step drill and reaming them out using my hand reamer, I got out my rivnut puller and high strength loctite and put those in place.
Holes enlarged for the rivnuts Rivnuts installed

With the Vertical Stabilizer completed, I then did a quick test fit and mounted it on top of the Fuselage and also attached the Rudder for a moment – almost looks like an airplane.Completed Vertical Stabilizer  Quick test fit of the Vertical Stabilizer and Rudder

Timelapse of building the Vertical Stabilizer

Vertical Stabilizer Structure

Hours: 3

After finishing attaching the rivnuts to the rear spar parts the other day, I put everything together and did a brief test fit with the Fuselage where it attaches into. Vertical Stabilizer rear spar in place with the Fuselage

After putting together the rear spar, I also enlarged the holes in the spar so that the M4 screws can actually be screwed in and enlarged the bottom two holes so that the bottom rivnuts sit flush with the spar.
 Holes enlarged for the M4 screws and bottom two holes enlarged for flush fit of those 2 rivnuts,Screw holes enlarged and the bottom 2 rivnuts made flush with the spar

Looked all good, so onto riveting together the inner structure of the Vertical Stabilizer.Riveting the rear spar of the Vertical Stabilizer Adding the inner ribs to the rear spar Structure coming along Inner structure of the Vertical Stabilizer riveted together

I also enlarged the holes for the wiring and added snap bushings since the inside won’t be accessible once it’s closed up and the snap bushings have a better durability than rubber grommets.
Snap bushings for the wiring

There was one spot on the rear spar where one rivet was very close to one of the rivnuts and I had to use my manual hand rivet gun to pull the rivet as the head of the Milwaukee was too large to get in there.
Clearance between the rivnut and the rivet was very tight so I had to use my hand riveter instead

Completed inner structure of the Vertical Stabilizer:Completed structure of the Vertical Stabilizer

 

Lots of Rivnuts on the Vertical Stabilizer

Hours: 1.5

After putting the Elevator construction on pause due to the alignment issue of the center rib. I decided to get started on putting together the Vertical Stabilizer. I’ve heard back from the Factory and it turns out that they’ve changed the Rib and will be sending me the correct new versions of the ribs (EL-RIB-001-C-E-1 & EL-RIB-101-C-E-1), so I’ll have to wait until I get those.

So onto the Vertical Stabilizer – the bottom of the rear spar holds a lot of M4 Rivnuts, so it was time to updrill the holes to the correct size in order to fit the rivnuts.Getting my tools ready to install the rivnuts

Using the step-drill bit I enlarged the holes just a bit smaller than the Rivnuts and then finalized it to the exact size using a hand reamer since you don’t want the hole to be any larger than the not so it gets a tight fit.
Hand reamer marked to the correct size using masking tape Test fitting Rivnuts after reaming them to the correct size

Once I was done enlarging all the holes I took care of deburring the holes and then went to work installing all the rivnuts using the Astro ADN14 Rivnut puller attachment for my drill and adding Loctite 277 (red) Threadlocker for added strength.Before deburring the holes after I enlarged them Tools ready to install the rivnuts Rivnuts installed using my bench vise to hold the bracket in place Done installing all the rivnuts

After all that was done, I put together the spar with the brackets for a quick test fit. While doing so I also found an error in the instructions, which say to rivet the hinges on the bottom with 8 (4 a side) 4mm rivets, but actually, only the center one (where I have black clecos) should be riveted, the outer ones will be bolted to the Fuselage (which is why they have larger holes already and I temporarily used the larger golden clecos to hold it in place), so I sent the Factory a note to correct the instructions.
Vertical Stabilizer Rear spar with brackets clecoed in place

More Elevator priming & assembling center spar structure

Hours: 5

With the weather warming up, I got to spend some time sitting in a bit of sun with the garage door open and preparing, deburring, cleaning and then priming more parts of the Elevator.

Laying out and preparing Elevator parts Primed Elevator parts

Assembling Elevator center spar

The first thing I put together was the Center Spar itself, which I had primed already together with the counterweight the other day. Setting everything up was pretty straight forward as usual and while I was working on it I had a visit from another builder of the EAA chapter I’m part of who actually happens to live very close by and is building an RV. And then another friend was visiting and I happened to have some rivets ready to be riveted, so I continue my new tradition to have guests pull a rivet on the plane and sign it.

Elevator Center Spar Elevator Center Spar riveted

Assembling the center structure to the spar

After the priming from yesterday had some time to dry and set, I went to work to put together the center rib assembly with the center spar. There are a lot of pieces that slot together in there, so it took some time to figure out what slots into which piece. for the center channel to go on:
Center Channel in place

Unfortunately I encountered a problem with the alignment of the holes on the center Rib, both left and right, with the plate as seen below:
Rib holes misaligned with the center plate Closeup of the misalignment of the elevator rib

In trying to figure out which piece is wrong, I started putting together more of the structure temporarily with clecos and the strange thing is that the other holes on the ribs are aligned fine (the black clecos below), so then I thought that it must be the top center plate.

More of the Elevator center structure in place

But then I took off the center plate to check its alignment with the outer skin and there the holes of the top center plate align correctly with the holes on the skin. So this in turn then lead me back to determining that the top (and bottom) holes on the Rib 1 must be the culprit.

It is very strange since the misalignment is pretty severe. It definitely doesn’t look like this could just be resolved by up-drilling the holes, so I sent a note to the factory to ask how to proceed. My guess is going to be that I need new center ribs.

 

Elevator priming & counterweight riveting

Hours: 4

While I was waiting for some parts to complete the ribs for the Vertical Stabilizer, I got started working on the Elevator. Since there are a lot of parts to the Elevator I broke it down into smaller tasks, first preparing the parts of the center counterweight and then I’ll continue next with the other parts of the structures.

So onto another session of preparing the parts, deburring holes and edges and cleaning with Simple Green & degrease with MEK. After that was all done it was back into my small paint booth to prime everything.
Cleaning Station in action Cleaning the Elevator parts with Simple Green Priming the counterweight parts Priming some of the Elevator channels Priming some of the Elevator parts

Riveting the Elevator Counterweight

After all that had time to cure for a day I went to work to put together the center counter balance weight support (that’s a mouthful).
I found a small error in the instructions that say that there are 14 rivets in the center, but it’s actually 16 rivets. Sometimes with these small errors I wonder if they are intentional to keep us builders on our feet to make sure we “measure twice and drill once” – I sent the Factory a note to correct the error in the instructions for the next iteration.

So after I laid out all the parts I put everything together using clecos and the two AN3 bolts and then went to work riveting it together. A friend was visiting from Ireland as well, so after a tour of the garage and everything he also pulled his first rivet and I had him sign his name under it.Parts of the Elevator Center Counter Balance Weight Support laid out Everything clecoed together Done riveting the Center Counter Balance Weight Done Riveting the Center Counter Balance Weight

Rudder Timelapse video

I also recently finished editing together the work on the Rudder, so here’s the completed Timelapse video:

Rudder Tip fitting & riveting the skin

Hours: 2.5

After having primed the inner surface of the Rudder skin the other day, I had all the pieces together to start working on finishing the rudder.

I attached the skin onto the structure and clecoed it into place.Rudder skin clecoed in place

Fitting the fiberglass tip

Once that was done, I went to work to fit the fiberglass tip onto the skin. I had to trim a little bit away from the bottom of the fiberglass. I made a first rough measurement, trimmed it away using my Dremel and then tried to fit it in.
First trim mark on the fiberglass tip

After aligning it all, I did a second small pass to trim a tiny bit more, placed it into the skin again and then it looked all good.
Tip fit in place and held in place using some clamps

Since the instructions are very explicit to make sure that the alignment of the rudder is perfect, I checked the alignment from all sides and it all looked good.
Rudder checked for alignment using laser level Rear of the rudder checked for alignment using laser level

After all that looked good and triple and quadrupple checking that the fiberglass tip sat flush in the skin I made marks for match drilling the holes and then went to work and carefully drilled the holes into the fiberglass.
First few holed drilled into the fiberglass tip Finished drilling all the holes in the fiberglass tip

Countersinking the front of the fiberglass tip

Once that was done, it was time to countersink the holes in the front. The instructions contradict themselves – only the first 7 holes get countersunk rivets, which mathematically adds up properly to the 32 rivets (2 x 7 on the top and 2 x 9 on the bottom = 32). So after counting all the holes and re-checking the instructions and doing basic math, I decided to only countersink the first 7 holes. I sent an email to the factory yesterday and they confirmed that I was right and they’ll fix the instructions in the next iteration.
Instruction error about countersinking

Before I went to work with the countersinking, I calibrated the micro stop countersinking tool using a scap piece of Aluminum to ensure the depth was set correctly and made sure that I had the correct 120 degree pilot cutter in the tool (I made a whole post about why using the 120 degree pilot was important here).
Calibrating the Microstop Countersinking tool Making a test countersink on a scrap piece of metal

After all that was ready, I went to work, mounted the fiberglass tip gently in my bench vise and started drilling the countersink holes.
First countersunk hole drilled Checking depth using a countersunk rivetAll the countersunk holes drilled in the fiberglass tip

All the countersunk holes came out well and everything sits flush now.
Flush fit of the fiberglass tip in the Rudder

Riveting the skin

So after all that I went to work and started riveting some of the skin.Time to rivet the Rudder skin The close quarter wedge came in handy for riveting in this tight spaceRiveted part of the Rudder skin