Vertical Stabilizer 6-1 to 6-2

I started building my RV-10 on June 29, 2022. The first section in the plans has me working on the vertical stabilizer (Section 6 in the build plans), so I pulled out all the main parts needed for this section. Below you can see all the parts laid out. Here I had already completed the first step of the build which involves cutting the left and right spar caps using the band saw, and deburring them.

Parts needed for vertical stabilizer

A few of the parts (spar caps, rear spar doubler and ribs) had some to significant bow in them. I tried removing some of the bow in the doubler by gently bending it back some, but for the spar caps I figured there will be enough rivets holding it in place that I am not going to worry about it. Also, the plans don't call out for any specific straightening of the pieces.

Next I drilled all the matching #30 and #40 holes from the rear spar into the spar caps. The vise was very useful here in holding the spar securely as I drilled. No issues with drilling other than it taking a while due to the number of holes and the thickness of the spar caps. My 20 gallon California Air Tools compressor needed a recharge every 3 holes!

I also applied some Boelube to the drill bits before drilling to see if that helps extend the life of the bits.

Drilling matching holes into the spar caps

Spar cap holes all drilled! At least on one side!

The next steps had me deburring the rear spar doubler. I used my flat files to remove the nubs on the sides of the doubler (an artifact left over from the forming process) and my bench grinder deburring wheel to round over the edges and corners. Inside edges were deburred entirely with files and the Cleaveland edge deburring tool. Once again the vise was very useful here,

Preparing the rear spar doubler

Now it was time to prepare and attach the rudder hinge brackets to the rear spar. For this I had to upsize the holes from the original size (something less than #30) to #19 for a #8 screw. Given my previous experiences with upsizing holes by large amounts in a single step, I decided to upsize the holes gradually by drilling them first to #28, then #21 and finally #19. I chose these step sizes because those are the drill bits that I have. Upsizing the holes went well as long as I didn't put too much pressure on the bit while drilling. Pushing too hard resulted in the bit catching and then me having to wiggle the bit side to side (without drilling) to loosen and remove it. Ultimately all the upsized holes were clean and round and I was happy with the results.

Attaching the rudder hinge brackets to the rear spar

Using AN509 screws to help with alignment while upsizing holes for bottom rudder hinge bracket

The final steps on this page had me countersinking several #30 holes in the rear spar doubler, and the 4 #19 holes (also in the rear spar doubler) for the bottom rudder hinge bracket. I used the #30 countersink and the #8 screw countersink for these holes and gradually dialed in the correct depth on the countersink cages. Once dialed in, all countersink holes came out consistently and the rear spar work was done.

Countersunk #19 holes for bottom rudder hinge bracket. Note use of tape to prevent me from countersinking holes that are not supposed to be countersunk.

Vertical stabilizer rear spar ready to go

Build Hints

• Use a vise to help secure parts for drilling, deburring etc. Mine is a Wilton 6" bench vise and works great with nylon pads to protect the clamped pieces.
• Upsize holes in smaller increments if necessary to reduce the bit getting stuck while drilling, and use just enough pressure to keep the bit rotating.

Time Taken:     7.5 hours

Dates:                June 29 - July 1 2022

Vertical Stabilizer Total Time:    7.5 hours

RV-10 Build Total Time:              7.5 hours

Video Note

I am still experimenting on the best format for time lapse videos of the build. I tried removing repetitive parts (deburring, drilling etc) from the videos, and changing camera angles, but figured this takes too much time and effort. As the videos are more of a support tool for my build log, I have decided to just record everything at a 10x rate (rather than 5x) and mount the camera to give an overview of my workspace. This will save me a lot of time in editing videos that I can then put towards the build. I'll continue to take close-up photos of any detailed work that I shall add to my logs here.