« Posts tagged canopy

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.


Skin and canopy on!

2 hours.

I managed to get home for an hour yesterday from work (yes, still working the occasional weekend) and Dave came over to help me finish riveting the top skin. We got that done, and today, I think I blew my back out trying to get the canopy back on. It wouldn’t slide into the blocks, no matter what, and I couldn’t figure out why. That’s when I had one of those dark moments and issued forth curses and bile.

This is the MGL IO eXtender. It is placed on the subpanel between the instrument panel and the firewall. It is also directly in the path of the canopy frame. In retrospect, I probably should have marked out the 1 3/4″ zone in which nothing should be placed. But I didn’t. At this point, I’m like, whatever. I can move that. I think. Actually, not really. Not too many other places I can put that thing without some rewiring and I wanted the canopy on TODAY. So I came up with this:

Originally, I had a backing plate on the IOX because of the way the mounting tabs worked. Since this thing weighs basically nothing, I’m pretty confident that the arrangement here will be just fine. Now the canopy frame clears.

All that aside, I will be paying dearly for the amount of crouching and wrestling I had to do to get the canopy back on the aircraft. It’s not terribly heavy, but it’s awkward, and fragile, and it took quite a bit of work to get it into place with the hinge pin holes lined up. But it’s now on. When I get back from Seattle, I’ll put the struts back on, and then it’s hurry up and wait for some hangar space.

More odds and ends.

5 hours.

Mostly a cleanup day. And a rearrange day. And a figure-out-what-to-do-next day. So there was cleanup. I rearranged the guest house bedroom and gained back a few more precious square feet. Then I went over the construction manual and checked off things I know I did but didn’t check them off during the actual work, mostly from wing mating. After that, I screwed the panel back on and started tinkering with the throttle quadrant. I didn’t get far with that. I needed to get the canopy out of the attic. It was beginning to drive me nuts that it was sitting up there, with the spiders and the heat. So I brought it down and then I realized I’d never put on the canopy latch handle or the outside canopy lift tabs. Not fun, but necessary. I hate cotter pins. I got the handle and tabs done, then had to take the canopy off and put it up in the rafters of the main shop. It’s pretty empty right now. More parts are on the plane than off it, at least parts that came with the kit. Oh sure, there’s lots of fiberglassing to be done on the empennage tips, wheels, landing gear etc.

But I’m at a crossroads: What next? leave the airframe for a while and do the O- to IO-360 conversion on the engine? Order avionics and start wiring? Or just do it all. Go to town. Work on the wiring while i’m waiting for engine parts and vice versa. But something tells me I’d rather not have nasty stripped-down engine between the plane and the workbench for extended periods of time unless that’s all I’m working on. Engines can be whole projects in and of themselves. But the truth is, if I find enough nastiness in the engine when I pull a cylinder off, it goes bye-bye to be rebuilt by real engine builders in real shops. If not, I replace cylinders as necessary, install the hi-pressure fuel pump, the new sump and tubes, the AFP FI system, and bolt it to the airframe. Fortunately, I’ve got all the parts for that, I think. I need to make a checklist for incidental parts, like hoses and gaskets, other stuff like that, and order it in advance. I also have to be singularly anal about the teardown process and not lose ANY PARTS WHATSOEVER and adhere strictly to the manual. This is no Oldsmobile Rocket V8.

Forgot about Saturday

8 hours.

Saturday was a pretty huge day in its own right. The night before, I’d cleaned up the workshop and put all the tools away so I could start making a fresh mess. I gloated over my handiwork in drilling the wing spars for a few minutes, then got going on the flap rigging. The flaps are attached at the trailing edge of the wing with a strip of piano hinge. The right side, the inboard edge of the flap rubbed against the fuselage, which didnt allow it to travel its full range of motion. So off it came, and I filed and scotchbrited off enough metal so that it did. However, in that sentence is contained about 4 or 5 iterations of trial, error, and scratching the crap out of the flap with the file until I got smart and put some tape around where I’d be working it. Eventually, it fit fine and was able to swing up and down, and in the ‘up’ position, the skin lay flat on the belly. The left side wasn’t a problem.

After that, it was time to reinstall the flap motor and rig the flaps. This is where the first setback occurred. The flap motor was one of the first things I did on the fuselage, so maybe I screwed it up, but there are many reports of the flap motor channel interfering with the canopy latch bar. Supposedly, they fixed this in the matched-hole kit, but I have a matched-hole kit and I’m telling you now, it ain’t fixed. What I had to do was put a 3/16″ spacer between the bushing block and the F-705 bulkhead to move the canopy latch bar forward enough so that it would clear the flap motor channel. I also had to change the rivets on the upper part of the flap motor channel to flush AN426 rivets. After this, I was able to see daylight between the latch bar and the channel. Of course, this also meant that the pushrod between the latch handle and the bar was now about 1/4″ too long. Put that on the list.

Then came the weird ceremony of drilling the flap pushrod holes. I”ll post pictures of this whole mess when I get the chance.

Some old business.

Remember how I said I wasn’t going to give you a play by play of all the iterations of goop? I lied. Here’s some pics of the process.

First round of sanding. This is just the black flox-resin buildup. I grabbed some stiff foam pipe insulation (redneck water noodle), a section about a foot long, from the hot water recirc pipe on the side of the house then wrapped it in sandpaper, which gave me a flexible sanding block with about the right radius for the fairing.

A few rounds after this point, I was ready for some glass.

Here are two of the strips of crowfoot laid out on the plastic, getting ready for wetting.

Yes, it is actually me building this thing.

The black electrician’s tape is the point at which I’d like to stop getting fiberglass goo all over the skin.   Forward of this,  I covered it with clear packing tape, which was a HUGE mistake, or at least it’s a huge mistake to use the cheap stuff.   I wound up picking most of it off with my fingernails in a time-consuming, arduous process that I’m not eager to repeat.   Word on the street is that the black vinyl tape plumbers and HVAC guys use (not duct tape) is perfect for this.  It also takes a couple of hits from sandpaper without turning into a scored mess.

Another shot of me.   Are you not entertained?

This time, I put the peel-ply on in little strips, which yielded much better results than trying to wrap long strips of dacron around that compound curve.

This shot, you saw in the last post.   This is after glass and before the next layer of flox, used to fill the divots.   After that layer, I switched to micro.   All of it tinted black.. Nasty stuff.

More Canopy fairing

5 hours.
Another combination entry, since you all don’t need a play by play on the iterations of goop happening with this canopy fairing, but beginning 7/2 and ending today I’ve done the final shape of the radius, put down 4 layups of 8-oz crowfoot glass, and a fill/smoothing layer of black-tinted micro. Shelley’s real good with cloth, so she helped do the layups, which was a bonus since it took 2 of us to get a canopy-wide strip of wet glass on there. I used the plastic-sheet/squeegee method to prepreg the cloth and we laid them up wet. That stuff stretches like crazy when it’s wet, because the weight of the resin pulls at it, as well as having part of it stuck while you’re positioning something else.. But the magic sponge did its job.. I was able to get everything to lay flat and the edge came up to the electrical tape boundaries I’d made.

This is after the peel-ply came off and I hit it with some 60-grit. I”m not going to show you every iteration of sanding, because I use my iPhone for music in the shop and I don’t want to get it full of dust, but suffice it to say that there are many iterations of this. Right now, there’s a bunch of black micro hopefully slathered into all the low spots, and tomorrow morning I get to sand it all smooth. I hope this works.