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Odds, ends, and annoyances.

6 hours.

Last weekend I had to work to deliver a product launch, so no airplane.   This weekend, I had a list, and I knocked out a bunch of stuff on it.  To sum up:

  • Tensioned and safety-wired alternator bracket
  • Removed protective plastic from aft canopy and removed tape residue
  • Relabeled mag switches and made “OFF” labels for everything else
  • Reconfigured quadrant for extra travel on governor
  • Added a wider heat shield to protect the throttle cable
  • changed out a too-short bolt on the purge valve cable bracket.

Apparently the way you do alternator belt tension is by increasing belt tension until it takes 12 ft/lbs of torque on the alternator nut to slip the belt.   That’s it.   That also gives you the 1/4″ deflection (on a new belt) called out by the usual procedure.   This is important, because a slipping belt can cause over/under voltage problems.  I did that, and safety-wired the bracket tension bolts together, like so:

Alt bracket saftey wire

Alternator bracket Safety wiring


When I put the aft canopy in all those many moons ago, I left the protective plastic on it, because why not?  Why subject the vulnerable plexiglas to my fumbling ministrations while I’m climbing in and out of the tailcone to adjust one thing or another, swinging tools and wires about?   Because once the canopy is attached, it’s difficult if not impossible to get all the plastic out from between the roll bar support and the canopy.   I had to put a space heater in the cockpit and run it for a while, until it was a balmy 75 degrees and the plexi and surrounding aluminum were warm to the touch.  I took out all the fasteners and removed the aft canopy section, which I put on the bench, then removed the rest of the protective plastic and cleaned off all the tape residue I couldn’t get to before.  100% better.

Protective plastic and tape residue gone

Protective plastic and tape residue gone


The magneto switches on the panel were cryptically labeled “MAG 1” and “MAG 2.”   I don’t know why I thought this was a good idea, and it broke with common practices in aircraft UI/UX design.   I relabeled them “L MAG” and “R MAG” because that made the most sense, and that’s how everyone else does it.   While I was in a labeling mood, I made about a dozen or so “OFF” labels to describe the down position of most of my toggle switches.   The double-throw switches like flaps up/down already had good labels in both directions, but there wasn’t anything labeled “OFF” anywhere.  The switch pointing toward the function described seems obvious to me, but apparently it isn’t to whoever wrote that reg at the FAA, so now everything is labeled according to the AC’s.


Like I said, there were odds, ends and annoyances.   Firewall forward, there was the matter of a heat shield, a too-short bolt, and the prop governor travel.

Heat shield on throttle cable

Heat shield on throttle cable

I did have a shield in place at this spot, but I remembered I had an extra double-wide one, so I put that one on in its place.  On the topside of the engine, I changed out the bolt holding the purge valve cable.   It was a temporary thing when I did it, and it didn’t have the required number of threads showing to meet spec, and since it’s pretty important that the purge valve remain closed in flight, it’s also important that everything connected to it is not half-assed.  This is what the proper bolt length looks like:

Purge valve cable bracket

Purge valve cable bracket

As to the prop governor, if you’ll recall from last time, the prop didn’t cycle at the low end of the throw.  The quadrant was only moving the lever arm about halfway through its arc of travel.   The simple fix to that was to drill a #12 hole about 5/8″ up the quadrant lever from the original one and voila, I get me 75-80% travel instead of 50%.   That story ended with a quick runup to 1800rpm and getting the prop to cycle, so that’s good enough for now.   Whether or not I have the rpm set right due to the arm position relative to the governor shaft is another story, and it will be resolved on either a full power run or first flight.  Even so, the engine is more responsive, now that it’s firing on all the plugs, which are now more or less synchronized in their ignition, so that’s a plus as well.

What was really awesome about this weekend was that for the most part, it was forward motion, not playing catch-up.  New things got done and good fixes were made, rather than unsuccessful stabs at a persistent and difficult problem.   There’s still a bunch of stuff to do to get ready for first flight, but I think if I can keep up the pace, I’ll be on track to fly it in early 2014.



5 hours.

Today was about putting things back together and getting a handle on some of the chaos.   The first bit of good news is that the oil temperature probe works fine.  I pulled it out of the engine and hit it with a heat gun and sure enough, it gave me a reading.  So I’m not going to worry about that anymore.   I secured the wires back in their bundle and i’m calling that squawk done.

I also wasn’t real happy about the weird way I had the fuel pressure sensor set up.  The Adel clamp holding it was maybe a size bigger than it should have been, and this way seems more secure:


As I mentioned last time, I flipped the governor arm over and it seems to work just fine:


My biggest problem with doing it this way was where the injector line was going to go.   A piece of angle solved that.   Now it’s out of the way, and less likely to be heat-soaked down near the cylinder.  I still haven’t safety-wired the screws yet, or put the cotter pin in the cable attach nut, But I think this is how it’ll stay.

Last week, Owen recommended tightening up the tailwheel chains.   Van’s recommends a half an inch of slack, but if you ask ten different people how they like their tailwheel chains, and you’ll get at least five different answers. But my chains had an inch of slack, and if I took a link out, I’d have none.  But I did take a link out of each side, and while there isn’t really any dangling slack, I can move the chains up and down by about a half an inch, and I’ll tell you, based on today’s test, it taxis just fine:


That little gap in the rudder fairing is kind of annoying.   Not exactly sure what to do there, except put nutplates in there and hope for the best.

Today’s test was all about seeing how things went with the cowl on.  First, I wanted to make sure I could actually get the cowl on with the flipped-over governor bracket making the cable rise a bit more than it did before.   Turns out, I’ve got about 1/8″ of clearance between the cable and the top cowl, which is good enough.   And from what I remember, the cowl inflates a little in flight, so that 1/8″ becomes a little more.   And that’s fine.   I just don’t want to have to put a clearance wart in the cowl to accommodate the cable.


But before taking it out for another test, this adjustment had to be made to the baffle material on the lower cowl.  I had to cut it back a bit, because it was covering up about 6 square inches of air intake.   Bad.   So with this mod in place, I put the top cowl on, and pinned it down.   Then I put a few of the floor panels in, and you’d be surprised how much the plane stiffens up with the reinforcing action of the panels.   I ran it up, then shut down the left mag.  Engine died.   Started it again, repeated.   OK, right mag dead.   Grr.   Still runs fine on one though.

So I said screw it, let’s taxi it around.  The new tailwheel chain tension was much better.  Now it’s more like Mickey’s Citabria, and the ground handling is nice!  I took it to the end of the hangar row, turned right, went down the next row, turned right again, then went back to the barn.  CHT’s never got above 210.   As soon as I get this mag situation sorted out, it’s time for ground runs.

\Last time, shutting off the left Mag made a lot of popping and missing, which I attributed to timing.   This time, I’m pretty sure the timing’s right, but now shutting off the right mag shuts off the engine.  Now, it might have something to do with the fact that I left the pop-rivet I was using for a timing pin in the hole when I pulled the prop through, but I can’t say for sure.   What I do know is that before, on the right mag, I had backfiring.   Now I’ve got squat.


EFIS returned to service and wing root fairings on

8 hours.

Today and yesterday.  I got the EFIS back before Friday’s taildragger lesson and got it back in the plane on Saturday.   My only gripe is that the voice alerts don’t make any sound.  I”m not sure if that’s because of the EFIS or the wiring, maybe both, but it worked before I pulled it out, and now it doesn’t.   More testing is needed there.

I did get the wing root fairings on, and hoo boy, are they a pain.  They’ll have to come off again for the DAR inspection, but I don’t need to access anything between the wings and fuselage, so they can go on the plane and not be hanging off the handle of my tool box.   It took some time, because the fairings and the seals are kind of awkward and I had to do a couple of passes with the deburring wheel to gain enough clearance for the u-channel of the rubber seal, but I think they’ll work OK.

I think we’re going to start the engine next week.   Time to quit procrastinating.   Need to torque the alternator bolts down, but other than that, it’s ready to go.   I’ll pre-oil it again, then we’ll fire it up.   With a gallon in each wing tank though, It’s not going to run for long.


Equal parts forward and back.

6 hours.

One of these days, I’ll move forward without moving backwards.  Today I had to dismount the EFIS in preparation for taking it to MGL Avionics.   Apparently the OAT module is fried.  I tried it with a new probe last week, no dice.   Maybe, if I’m lucky, I’ll be able to drop it off tomorrow on my lunch hour.   Other than that annoyance, I got the tailwheel hardware primed, something I should have done long ago, and I got my spark plugs torqued in.   But now, for some mysterious reason, the tailwheel steering chains don’t reach their mounting points on the rudder anymore.   It’s possible I had the steering link on upside down/backwards, which would have accounted for the missing 3/4″ of chain necessary to bridge the gap between what I need and what I’ve got.   Looks like I’ll be ordering another set of tailwheel chains.  Grumble.

Anyway, once I get my EFIS back from the shop, it’ll be time to prepare the engine for first start.

On another note, I’m progressing nicely in my tailwheel training.   We flew from Torrance to Hawthorne, where I did 8 landings, unassisted.   Apparently I CAN land a Citabria in 3-point attitude.   At least when the wind is coming at me and I set up the approach right.


8 hours.

A full day full of fiddly things.   And a cleaning.   The biggest thing today was moving the purge valve and alt air cables out of the way of the stick travel.  I was able to do  this by detaching the bracket from the underside of the panel, rotating it 90 degrees and attaching it to the throttle quadrant.   It’s not pretty, and I should come up with some kind of cover, but it will do for now.

I also put jam nuts on the forward elevator pushrod.  This was a chore.  Big fingers, small spaces, washers in between slices of metal.. you know the drill.

I fiddled around with the OAT probe wiring again.. Matt at MGL gave me a new one, but it doesn’t work either.   The EFIS comes out and goes to MGL again. 🙁

I’m glad I checked the elevators again.. Apparently I never put nuts on the hinge bearings last time I was fiddling around with rigging them.   This is now fixed.   I also cleaned up the plane and the shop, putting all the extraneous hardware and tools away, getting ready to make a fresh mess.

I still need to secure the cabin heat SCAT tube, but I did get my heat shields installed.   Then I began having all kinds of fun with the left side canopy strut mount.   One of the the screws is loose and it’s nearly impossible to get any kind of wrench in there to tighten it down, since it’s under the longeron.   Sucks.

This kind of stuff shouldn’t take 8 hours, but the awkwardness and inaccessibility of the stuff in question made it so.   I can’t wait to get back to straightforward stuff.

This Game Is Rigged.

6 hours.

Would have been 7, but I went for lunch with the Marks in their hangar down on the west end.   Split pea soup, garlic bread, and a video on the history of the F-14.   Mark S used to fly them in the Navy, he’s now building a Rocket.

My biggest intention was to fix the interference between the control sticks and the throttle quadrant, as well as the alt-air and cabin heat controls.   I was fully prepared to move the quadrant back, but as it turns out, I don’t have to.

I reset the rigging on the ailerons to neutral, and also tuned the sticks so that they’re just a hair outward of center.   This clears the quadrant, but just barely grazes the alt-air and cabin heat controls, so they’ll have to be moved.   This is less of a big deal than moving the quadrant, and now I know the wings are rigged as well as they can be.  The purge valve control interferes with the stick, but that should never be open in flight, ever, so that doesn’t bother me.  What does concern me is that while the wings and flaps align at neutral/flaps up, the trailing edges of the wingtips are slightly off.   I don’t know if this will result in a heavy wing condition or not, but I’m guessing it might.  The remedy for that is to split the trailing edge of the wingtips and fasten them back together aligned to the aileron.

You might be wondering why this single, simple operation took 6 hours.   Once the wings are installed, access to various things is far less convenient.   There are access panels, but these are now on the underside of the wing, in the dark.  In addition to that, the bolts on the control stick require washers that are extremely difficult to install, especially with large fingers, and with the nose-up angle of the aircraft on the gear, a dropped washer tends to roll back under the seat floor, requiring numerous fishing expeditions with a telescoping magnet.

Next time, I’ll have to address the fact that there is no jam nut on the forward elevator pushrod, which will require some crawling, but on the whole is more accessible and should be easier.

A Fix and Some Finishing

7 hours.

Although the last three shouldn’t count because I spent them fixing something I should never have had to in the first place.

20130728-192738.jpgThat little corner of aluminum is the bane of my life.    Since I put the wings on, I’ve caught it on shoes, shirts, and finally, the belt on my jeans.   When this happens, it bends.   This time, I bent the crap out of it, so badly, that I had to remove the fasteners on the skin, peel it back, and hammer it flat again.  The light makes it look worse than it is, but it’s still pretty bad.   Fixed now, though.


20130728-192751.jpgThe day wasn’t all bad.   I got the fuel pump overflow plumbed.   I used some of the tubing I had from the MAP sensor install to create a flexible link between the output of the fuel pump to the hard line shown here.   The engine wiggles.  The aluminum tubing doesn’t.   I need a flexible line between the two.

20130728-192805.jpgThe fuel sensors concerned me for a minute.   When I connected the wings, I had some little extra wires that I thought I’d run for spares.   I guess this is why you label things.   After some pondering, I realized these were the fuel level sender wires.   Duh.  The good news is that I didn’t have to do any splicing and apparently I cut them to the right length.   A couple of connectors later and I had fuel level, which was, of course, zero.

No luck on the OAT sender though.   Either my EFIS or the probe is bunk.   OAT reads a steady 32 degrees F.  Have to contact MGL for a new one.

Crotch Strap Bracket part 2.

5 hours.

I’d been avoiding it, but today I worked on the right seat crotch strap bracket.   I did the left one before the airport move, and I really should have done this one at home too, but I had bigger fish to fry at the time.   Today I got the bracket drilled and deburred, and got 3 out of 4 platenuts on, but one will have to come off so I can enlarge the hole.  Slight misalignment, and  fixable.

I just have to fix that and pop-rivet it in.   This side was easier to deal with because there wasn’t a trim relay board in the way, although I did have to cut down the aft part to clear a wiring conduit.

I really wish these had been included in the kit, and I’d installed them before I wired everything.   C’est la vie.  Wot’ ever.


Still more connections.

6.5 hours.

A bit of a late start.   Since I took this week off, yesterday was my first weekday commute to OXR.   I went via PCH, which is nice enough, but it took a little longer, especially during rush hour.

I finished installing the rudder cable linkages to the pedals, so that’s another thing done.   I also got the pitch trim servo wired in.  I’ll need to adjust the throw on the trim servo, but that’s essentially done.

Then I went back to wing wiring.   I got the strobe and lights connected for the right wing, plus the autopilot servo.  It was lots of tedious, fiddly stripping and crimping in small, awkward places, which has an extra coating of suck because I did something to my right elbow and now operating hand tools like crimpers is fairly painful.

Left to do is connecting the VOR antenna wire (This may become an ADSB antenna wire if they phase out VOR) in the left wing and putting in a couple of pieces of UHMW tape here and there.  If I can have lights, strobes and VOR by the weekend, I’ll count myself lucky.


The Thing Has Wings!

3 hours.

This morning, Dave and Peg picked me up from home and we met Derek at the airport to fly up to OXR in his 177RG Cardinal.  It took a while to get out of SMO because somebody’s bizjet blew a tire and was stuck on the runway for half an hour, but we finally got off the ground and got to Oxnard.   There, we put the wings on the RV, which involved a lot of shuffling things around in the hangar space and trying not to bash the other occupants, the structure, or each other, with ungainly airplane parts.

The wings did go on, after a fashion.   Our time here was abbreviated because of earlier runway delays, so the wings are currently held on with the sacrificial hardware store 5/16 bolts I used during the initial alignment and the proper AN5 aft spar bolts.  My hangar mate Ron and a friend of his helped us get the overlap sorted out on the right wing, and all totaled it didn’t really take more than an hour once we arranged everything in the shop and actually began putting the wings on.

It truly was a 4-person job.   Derek, Dave and I wiggled the wing into place, Peg kept the wires from getting fouled, and then I bashed the 5/16 bolts through with the rest of the crew doing precision wiggling where needed.





One thing I should have done is left the flaps off.   We tried getting the left wing on with the flap on and that didn’t go so well, especially when it came time to line up the aft spar holes.   I wound up taking the flap off the left wing, then took the flap off the right wing before we tried to put that on.   So what you see here is the current state, which is the big flat bits that make the plane stay up in the air, stuck to the bit that holds the meatbags off the ground.

As an aside, I’m hoping that when I connect the control push tubes, the sticks are a little more limited in their side to side travel, because currently, my hand just barely grazes the quadrant.