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More odds and ends

April 7, 2013 / posted in Electrical, Firewall Forward, Panel, Wings / No Comments

4 hours.

A few things here and there. I installed the MAP tubing and put a couple of heat shields on the pipes to protect the throttle and mixture cables. I also installed the canopy seal, which is going to need some assistance from some RTV or proseal. I do think firewall forward is just about done, though. The cabin heat SCAT tube rubs on the engine mount a little, but some UHMW tape should fix that. The two things I did that were of major importance were the autopilot test and getting that ridiculous piece of lead off the flange of the left elevator counterweight rib.

A while back, I’d balanced out my elevators, or so I thought. You’re supposed to put the elevator tips on, then drill holes in the lead weight until the elevator balances. Well, guess what? You’re not supposed to have the elevators connected when you do this. I discovered this, freaked out, then riveted a flat piece of lead (cut from an extra counterweight) to the outboard rib.

When I put that away, thinking I was just about the smartest cat in the whole barn, I started imagining the kind of beating a control surface takes in flight. So what happens to a little piece of lead riveted to this structure with a couple of Cherry countersunk blind rivets? The piece of lead comes off and somehow jams the elevator in the dive position and I go screaming downward like a holed Stuka, straight into a busload of orphans on the 405. This has bothered me for months, but I could never find a good opportunity to fix it until Saturday. I drilled out the rivets and put the lead back in a drawer. I also read about a neat trick you can do when balancing your elevators: Pour some lead shot into the tip through the tooling hole in the rib until th elevator balances out, then stick it in place with epoxy resin. Even if it’s not perfect, bias it a little heavy, because paint will change the balance.

I also mounted the MGL GPS antenna on the top side of the glare shield. It works; I get an intermittent GPS position while still inside the guest house.

Oh and one other thing: I dragged the wing cradle over to the shop and tested out the bank servo of the autopilot. Since I actually followed a wiring plan and wired the fuselage-side and the wing side according to it, I was able to test out both servos simultaneously. I do need to make a new ground connection though. The ground from the servo bracket sucks and I was only able to get a good ground by cleco-clamping the ground terminal to a wing rib.

More bits and bobs

November 18, 2012 / posted in Electrical, Firewall Forward, Panel / No Comments

5 hours.

Since we’re now undertaking a remodel of the downstairs (as if it’s not crazy enough around here) the pressure is on to get the plane done and get it out of the guest house. I’ve been finding all the fiddly things to do and doing them, per last week’s list.

The alt air cable adventures continue. The bracket’s done, and now there’s a hole in the firewall. Suck part is that I have the wrong eyeball, I need the .188 and I have the .210, so it doesn’t actually seal much of anything. New one is on order. I reinstalled the flap brace and drilled the horizontal stabilizer to the the fuse. I had to do this because I replaced the HS-710 bracket a while back because it was crap and I never got around to it.

The panel is also labeled! This is quite nice, but I still need to put the N number on it, as well as the placard that says, “I built this plane, so don’t go looking for certification.”

Cooling blast tube for the alternator is installed, but only halfway, it needs to be secured in such a way that it blows on the alternator. Other blast tubes need to be installed for the magnetos, and then I have to get serious about hoses and control cables.

FWF Sensor Wiring DONE!

October 29, 2012 / posted in Electrical, Firewall Forward / No Comments

10 hours.

This is yesterday and today. Yesterday started with an epic shop cleaning. I have those every so often, and it’s helpful, extremely good to have a workbench devoid of clutter, if only for a little while. Stuff got put away, stuff got tossed out, floors got swept and vacuumed.

The fiddling with the FWF stuff has been progressing as well as I can make it, and the wiring has been a bit of a challenge, especially since the K-Type wires on 2 of the sensors were too short to make it all the way to the RDAC engine monitor module. Then there’s the business of where to actually run things so they don’t rub on other bits or get roasted alive by the exhaust pipes. I got the current sensor done, although I suspect I’ll have to flip it over, I got all the temperature sensor wires run, wrapped, and grounded. About the only thing that didn’t happen is the MAP sensor, which needs a 1/8″ to 1/8″ barbed elbow fitting. Searches have turned up no such animal so far. But technically, that’s not wiring, so legally speaking my FWF sensor wiring is done.


Here’s the beginning of the attachment process. The overbraid K-type wires are a ratbastard to work with. They’re a little like shielded cable, but they’ve got an extra woven sheath below the braid that absolutely sucks to try to get off. Maybe there’s a trick to it, but this was by far the worst suckage of this task.


A slightly different angle. On the RDAC (the grey box), the first 4 pairs are exhaust gas temperature thermocouple inputs. Can’t change them, which kind of sucks, because then I wouldn’t have had to extend a couple of TC wires to make them reach the proper input. Oh yeah, splicing TC wire sucks too. The ty-wrapped snarl at the bottom is the FloScan fuel flow sensor wiring. I installed the FloScan months ago, but never got around to properly wiring it until today.


Still a rat’s nest, but there is progress there. This is right after grounding all the things that needed grounding, being the FloScan, the tach sensor, and the RDAC itself. The EGT and CHT probe wires haven’t been cut to length yet, nor have they been secured by Adel clamps to the firewall.


Ahhh, that’s better. Still some wrapping to be done, but all the wiring is secured and attached.


This shows the oil pressure sensor hooked up and run into the bundle. This will benefit from a couple of Adel clamps attaching the main bundle to the engine mount, but we’re in a pretty good place.

Even more fun: Once I got everything wired, I fired up the EFIS and decided to test out whether or not I’d actually inserted the right wires into the right terminals on the RDAC. This was done by means of a heat gun and a blowtorch. The heat gun raised the temperature of the actual cylinder itself so I could check the reading on the EFIS. The blowtorch was for the EGT probes. Suffice it to say that the method of testing was a great success: I found I had miswired the 1 and 3 cylinders for EGT, and the 2 and 4 cylinders for CHT. It is now all fixed.

Oil Door.

March 13, 2012 / posted in Electrical, Firewall Forward, Fuselage / No Comments

6 hours.

Yesterday and today.
Yesterday I worked on the oil door. The finish kit comes with a fiberglass version, and it’s meant to be held down with an elephant-ear Camloc fastener, but it looks like ass if you do it that way. A better alternative is the Nonstop Aviation hidden hinge kit.


It mounts the door on a sprung hinge that opens up and out of the way of the cowl. You can use the fiberglass part from the kit for the actual door, but like some others have done, I made mine out of .032 aluminum. The reason? When the fiberglass part gets heated by the engine, the pressure from the hinge trying to open will warp it. Aluminum has no such limitation.


Once the door is cut, formed and drilled, the flush-mount Camloc release latch goes on. I actually made two of these things, because I screwed up the Camloc location on the first one. No biggie. I still have half of a .032 horizontal stabilizer I’m using for stock.


When it’s all in place, it closes flush and latches properly, but getting the hole for the latch handle was kind of a bear.


When it’s open, the spring keeps it out of your way so you can check oil, remove hinge pins, etc.

Today I was doing more checks of things under the area where the top skin will go, because that’s going to have to go on soon. I spent some more time securing wires and torquing down Adel clamps. In doing so, I found that I never riveted the row on the longeron right next to where the canopy closes. They leave them open at the QB factory because the slider canopy mounts a little differently. This isn’t all that easy to deal with when the panel and other things are installed, but it’s not that bad either. All I had to do was disconnect the vent hoses so I could get hands and bucking bars up inside the channel by the longeron.

After that, I started putting the baffles back on, but didn’t get very far. I’ll do some more of that tomorrow.

[Untitled]

January 4, 2012 / posted in Electrical, Fuselage, Panel / No Comments

Here are some pics from the last couple of weeks.  I’ve recovered my server-side image processing script, so I promise more photos in the future.


This is the mess before I cleaned it all up.


Flap actuator and servo reinstalled (Yay!)


Fuel pump reinstalled, lines secured.


This is me working on the endless process of dressing cables and zip-tying everything.

Avionics Install (almost) DONE!

January 3, 2012 / posted in Electrical, Panel / No Comments

4 hours.

Sweet FA got done over the weekend (New Years, hangover, etc, etc.), but today I finished wrapping and securing various wires, as well as rerouting the starter ground in a bundle instead of floating around all by its lonesome.

Only two things left to do, really, and that’s to install the OAT probe and reconnect the IOX when it comes back from MGL in a couple of weeks.  For now, i’m not sure whether or not to start the baffling or the FWF sensor wiring.

It’s on again.

December 29, 2011 / posted in Electrical, Fuselage / No Comments

12 hours.

That’s today and yesterday.   Shelley helped me rivet on the cover plates to patch the holes in the hull I drilled in search of better antenna locations.  There were 3, total.  One down in the tail, one under the baggage floor, and the original one just forward of the spar under the EFIS.   Since I had her in the plane, i was able to reinstall the transponder antenna properly; I’d taken it out to see if that hole might be a suitable location for the COMM antenna.   It wasn’t.   When we got that done, I went to work on putting the pax side floor back together.  Since I had access, I was able to wrap and secure all the cables going aft under the floor, and I can still access the antenna connection under the seat floor.  After that, I spent a lot of time with cable wrap, securing all the loose wiring running down the tailcone.  I took the advice of someone on VAF, who said something along the lines of “start at the tail and work your way forward, finishing everything you can possibly finish.”   Practical matters preclude me from absolutely finishing the tail section right now, but everything else got done and done.   I torqued down the autopilot pushrod bolts (been driving me crazy for a while), and secured all the wiring of the ELT and strobe pack.  The ELT wiring got secured with a length of shrink tube around the idiot DIN connection (phone cables and stereo connectors?  WTF, ACK Technologies?)  providing NMEA GPS info to the ELT.

Alphabet soup, I know.   We airplane people love our acronyms and abbreviations.

I still have one or two loose ends: I need a special platenut to completely finish the baggage floor, but that should be here tomorrow.

Today I started seeing the end of all the disassembling necessitated by having to wire the aircraft.  I got the flap actuator and flap motor put back in, but this time wired in properly with wires secured in the tunnel.  Lo and behold, I was also able to install the flap arm covers in the baggage compartment, something that hasn’t happened since the interior was painted.    I also cable-wrapped the cables running forward of the spar past the fuel lines and locked those down with cable stays, so nothing’s rubbing on anything.

I also began work on reintegrating the control system on the sticks.   A while back, before I knew what I was doing, I overstretched my trim springs and had to get new ones.   I’ve since gotten them, and was working on getting the sticks all back in order.   I had to paint the steel connectors for the springs, so that stopped while the paint is drying.  I started futzing around with the hard fuel lines on the floor, but didn’t really get anywhere.

Tomorrow I should be able to finish the sticks and see if I can’t get the fuel lines secured (they need a couple of Adel clamps to keep them from vibrating too much) and install the fuel pump permanently.

Antenna installed. Again.

December 23, 2011 / posted in Electrical, Panel / No Comments

5 hours.

The COMM antenna is installed.   I finally wound up routing it along the longeron and down through the center section channel, then back to about where the seat floor panels join.   I was able to keep it from running alongside any wires for very long, but there’s some contact where it has to pass through the spar.   I swear, running wires fore to aft in that thing is a pain.

I got the antenna installed in a good spot, it’s more than 2 feet away from anything interesting, but I need to test it with my ghetto ground plane strips, since it won’t have a proper ground plane until the wings are on.   Even so, I can hear SMO traffic and with the squelch off, a little bit of ATIS.  Pressing the transmit button causes some sensor weirdness, but I imagine that will go away with all the dangling wing wires connected and once the plane is outdoors and not surrounded by metal shop equipment and other various RF-bouncy things.

So next is to finish cleaning up the strobe cables running aft (since I can get to them with the floor panels off), then put my floors back together.   Then the flap actuator and the control arms, fuel pump, etc, etc.

Music, ELT, ELT-GPS done.

December 22, 2011 / posted in Electrical, Fuselage, Panel / No Comments

6 hours.

I know there’s been a dearth of pictures lately, but there isn’t a whole lot to shoot.   Mostly I’ve been cleaning up wiring.   Today is a win, though.  The ELT has been a ratbastard since I first clicked ‘Add To Cart’ at ACS in March.  After the interminable wait, I was presented with the need to run a 4-pin phone cable along my central wire bundle.   A cheesy phone cable is not the first thing I’d pick to run the remote head of a potentially life-saving device, but it’s not my call, I didn’t design it.   This phone cable connects to an audio annunciator, and from that, another cable goes to the panel-mount remote control, which lets you fire off the ELT through blood-fogged vision if it hasn’t gone off from impact and you need help Right Now.   Today’s important lesson: Use the right tool for the job.  Well, no shit, but the thought of paying $40 for a tool I’d use on this project exactly once galled me, so I didn’t buy the phone line connector crimp tool.  I should have.  I spent a good while debugging why switching the ELT to ‘ARMED’ produced no beep.  First thing was that there was no battery in the audio module.  This required a CR2-type lithium battery, which the Radio Shack down the street had, thankfully.   The other thing was that without the crimp tool, the connector on the phone cable didn’t exactly work right.   No beep, no nothing.   I had already made one run to the Shack for the battery.  Now I had to make another.   But then I remembered I needed a 3.5mm mini plug extension so I could test the music input.   With products in hand, I went home and got back to it.  Sure enough, my crap connector job on the ELT cable was the problem, so with the connector installed properly and the battery in place, switching the ELT to ‘ARMED’ gave a satisfying beep.

Before I went my 10 rounds with the ELT, I’d soldered the 3.5mm snap-in CALRAD jack to the Music 1 cable, making sure to stress-relieve it with shrink tubing.   Once I had my 3.5mm cable, I was able to hear my iPod playing back Geomatic’s “Bliss” just fine.   Some adjustment may be necessary to increase the volume on the audio panel, but that shouldn’t be a big deal.   The level is also regulated properly by the audio panel.  When a radio transmission comes in, the music mutes, then comes back up after the transmission is completed.  The only thing that bums me out about the GMA340 is that I don’t have a music on/off switch, which means I’ll have to pull the plug if I want the music to just plain go away.   Fiddling with an iPod in flight is not a good idea.

So yeah, today’s a win.   Tomorrow, I need to think about mounting the comm antenna, running the comm wire, and putting my floor back together.  Then when all this avionics BS is done, I can put my flap actuation system and control arms back in.   Maybe even seats!   Then it’s on to the wonderful land of Firewall Forward, but not before a hellacious shop cleaning.

RDAC and Emergency Batt switch

December 21, 2011 / posted in Electrical, Panel / No Comments

3 hours.

Just got back from a 2-week work trip, so I needed a little downtime.   Today I got back into it and wired in the EFIS backup battery switch.  This was wired before, but it was crap, so I redid it.   I also wired the RDAC ground to the engine block, like it says to in the manual.   Apparently wiring it to the secured supply on the EFIS is not correct.   I also got started on wiring the music input.   Took me a second (and the brave sacrifice of a 1/8″ splitter) to figure out which was Tip/Ring/Sleeve, but all that remains there is to drill a hole in the panel, solder the wires on, and snap it in.

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