I’m in wing rib hell. Try as I might, I can’t do this every day for hours on end. So, I’ve been devoting an hour or so each day after work for the past week deburring holes and flanges. And since I probably get too worked up over smoothing the edges, it’s gonna take several sessions.
Wing rib prep
Time to rivet all those rear spar parts together. Follow the advice in the plans to tape up those holes that aren’t to be riveted at this time…those -4 rivets aren’t fun to drill out.
Rear spars being riveted
And here’s the finished product. Success rate on these rivets was 100 percent…no drill-outs required!
Rear spars completed
It’s getting darker earlier, and I didn’t have much time to get parts primed after work – so I just did the stuff previously alodined.
Rear spar parts primed
I had two more work trips during the last two weeks, so there isn’t a lot of visual progress to report. This entry is the culmination of bits and pieces of work done around travel and family stuff.
After the front spars were prepped, the next step was constructing the rear wing spars. The first task in this process was deburring the spars themselves and match-drilling aileron reinforcement plates to them. Nothing difficult here, I just followed the plans – with one minor exception.
These reinforcement plates fit snugly up against the rear spar’s upper flange, and I match-drilled the #40 holes on each spar flange and reinforcement plate. The instructions don’t specifically call for dimpling these flanges before the rear spar is riveted together, but it would seem to be easier to do it now while the parts can be dimpled separately…so that’s what I did.
Rear spar reinforcement drilled
Note the aileron pushrod hole cut into the reinforcement plate. The location of this hole is traced onto the plate during match-drilling. A Dremel tool with a carbide cutter makes quick work of “roughing out” the hole, and a sanding drum on the Dremel takes care of the rest.
The rear spars’ attach plates and associated doublers are actually RV-8 parts, and must be trimmed according to the plans.
Rear spar attach plate drilled
After deburring, countersinking and dimpling the reinforcement and doubler plates as required, I alodined them using the always-handy Touch-n-Prep pen.
Rear spar parts alodined
Got the tiedown plates riveted together and bolted onto the wing spars today.
Tiedown attached
Time to ease back into RV building. Did a lot of nutplate riveting…thank goodness for the pneumatic squeezer!
Lots of nutplates riveted
Got back from Fairbanks, Alaska…it was a long, tiring trip. But we finished everything we set out to accomplish, most of which involved flying helicopters in icing. Here’s a pic of the test aircraft after an hour or so in clear ice.
Sponson ice
Fairbanks is an amazing place for airplane nuts. Some airplanes that you’d see in museums in the lower 48 states, are flying every day in Fairbanks hauling supplies to outlying communities. Here’s a Curtiss C-46 departing Fairbanks International (PAFA) with a load of fuel oil.
C46 departing PAFA
And here’s a very rare find…a Carvair. It’s a DC-6 that was modified decades ago to carry cars, and only a handful still fly.
Carvair at FAI
On my day off I managed to log some float time with a flight from the Chena Marina float pond, just a mile or so west of PAFA.
Landing at the Chena Marina
Another rare bird…a Turbo Otter at the float pond.
Turbo Otter at Chena Marina
I’m heading to Alaska for two weeks, so the goal for today was to finish match-drilling the tiedown plates and associated nutplate mounting holes, then to prime the plates, spacers and also the countersunk main spar holes. By the time I get back from Alaska, the weather here may be too cold to prime parts outside. Here are the tiedown plates.
Primed tiedown plates
And here are the spar countersinks.
Primed wing countersinks
With the spacers fabricated, the next step was match-drilling the spacers and tiedown plate to each spar. Some other folks have had problems getting the spacers aligned between the plate and spar. My approach was to mark two vertical lines on each spacer, each one halfway between the center hole and the left or right side. I then aligned and taped the spacers to the spar so that the vertical lines were centered in the spar holes to be used for match-drilling the spacers to the spar and tiedown plate
pacers in place
Here’s everything clamped/bolted together, ready for drilling.
Tiedown in place
I’ve been trading emails with Van’s over the last couple of days about the slightly enlarged holes in my wing spar doubler plates. Turns out that there really isn’t any problem, the enlarged holes are an artifact of the CNC punch process – and they’re ok. I don’t want to rehash the whole discussion on this page, so here’s a link to a Van’s Air Force thread on the topic.