Dave’s RV-7A Building Log

All of the plane’s wiring will funnel to two bundles along either side of the firewall recess and go through two holes in the shelf. I cut those holes and started feeding wires through. I also cut apart some more of the Stark harness and fed those wires around. In order to feed the autopilot wires through the small holes, I had to remove the DB-9 connectors. I wrote down which color was in which spot and then carefully removed the pins.

I also did some more thinking on where to put the holes in the firewall. I think I’ll have one hole off to the right for the engine sensors and one dead center near the top for everything else (alternator, P-mag, main feed, etc.).

It’s a great feeling to finally be jumping into the wiring. Now I just have a ton of wires to run back and forth.

August was a pretty productive month. I put in more hours than I have in over a year, and I’ve gotten the panel well on its way.

Adele’s soccer jamboree yesterday kept me away from the project. However, my order from B&C Specialty Products arrived, a large fuse block, 6 AWG wire, and some switches. They sent out the order on the same day I placed it! Wish I could say the same thing about SteinAir. It took them 4 business days just to ship my order. As soon as that gets here, I can hook up the battery to the fuse blocks and start powering stuff up.

I spent just a little time tonight messing around with electrical stuff. I gathered up all the switches and identified which one was going where. I’ve got one weird switch that I thought was for the flaps. I spent a bunch of time trying to figure it out, but turns out I have a different switch for the flaps. I have no idea what that other one is for.

I also started unrolling the Stark wiring harness and separating out the power and ground leads. So far the harness still looks about perfect.

One other item of note today. I called Advanced Flight Systems to get an update on shipping out the AF-3400 EFIS and EMS. So far I keep getting slipped deadlines. I’d really like to get the engine sensor harness so I can get the FWF finished up. They said 2 more weeks for that. And the units themselves should start shipping to the initial customers in 4-6 weeks. I should be near the top of the list as I placed my order right after Sun ‘n Fun. If I can get them by mid-October, I’ll still be in good shape. Much beyond that is going to start affecting the first flight date.

Still feeling under the weather today. I just did a little tinkering. Since the seat pans are permanently in place, I installed the flap weldment. I had to redrill a couple of holes in the baggage floor, since I replaced it a while back. The plans call for nut plates for the center flap weldment block, but I can’t see why. It’s much easier to just use Nyloc nuts, so that’s what I did.

I also re-installed the blocks for the canopy pivot points, and secured the avionics stack to the subpanel. The panel feels quite solid. So far I’m planning on leaving out the ribs between the panel and subpanel, but I can always add them later.

I thought a bit about the wiring runs along the firewall. I’m going to run them up either side of the firewall recess (which I didn’t need) and then through the shelf I just installed. Should work out pretty good.

I really wanted to start working on the wiring full bore, but the quadrant needed to get finished first. Access to it is very limited once the panel is installed. I installed all of the throttle quadrant cables and adjusted everything so the levers were getting a full range of motion. Unfortunately in order to do that the clevis end on two of the cables was only threaded on 1/4″. That’s not enough. I wanted at least 3/8″. So I moved the mount for the cable housing further aft by 3/8″ and re-adjusted everything (hopefully) for the last time. Leaning over the side of the cockpit working on this thing for hours today was a real pain. I hate to add up the hours, but the quadrant has added significant time to this project. Had I known, I certainly wouldn’t have done it.

The only way to get the forward side of the shelf riveted into place was going to be to lay in the cockpit. For that, I needed the seat pans riveted in. I left these off for a long time to faciliate wiring the pilot stick. With that done, the pans might as well go in permanently. It’s very cool to finally have them in place, although it was very cramped sitting in the cockpit to squeeze the nut plates along the central tunnel.

I figured I might as well install the aft push tube and hook up the forward push tube to the sticks. The connection between the stick weldment and the forward push tube was the most difficult bolt to install yet. There are two washers that act as spacers and the access is severly limited. I read about a trick of using super glue to hold the washers in place temporarily. Without that, there’s no way I would have ever gotten it done.

And last but not least, Julie helped me set the rivets for the shelf behind the subpanel. They aren’t pretty rivets, but they’ll hold just fine. She also helped me get the panel and avionics stack in place. I think it’s finally time for some serious wiring. A few parts are showing up this week and then I’ll be able to really haul. Now if I could just get the stupid engine sensor harness from AFS, I could finish up the FWF and electrical.

Crimped the ends on the starter cable after carefully trimming it to length.

Installed the throttle quadrant mount. The second picture shows much more space between the cable and the exhaust pipe. (Sorry about the dark pictures. I was too lazy to drag over a light and the flash on the camera is lousy.)

I also installed the shelf I made for the fuse blocks and other little boxes. I squeezed the rivets on the sides and tried to set the rivets along the firewall, but was having too much trouble with them. I’ll have to wait for help on those.

I also put in the throttle quadrant and started to get it hooked up.

Since I had to remove the throttle cable to swap it with the longer mixture cable, I decided I might as well make my own mount. The one from Van’s FWF kit causes the cable to be too close to the exhaust. I used some 0.125″ angle and .063″ sheet to make something that will work much better. It took quite a while, but I enjoy fabricating parts like this. And here are the two parts primed.

I also test fit the quadrant and cables with the mount I made a few days ago. Seems like it’s all going to work together. I tweaked the angle of the mount a bit. I also measured the throw of each quadrant lever versus the throw needed at the engine. Seems like I’ll need to drill some new holes to increase the throw. Both the throttle and mixture seem a bit short. Here’s the mount painted.

I wasn’t feeling good, so I didn’t do too much. I made cables for the engine ground and negative battery cable. They both terminate at the ground block on the firewall. Steve’s crimper does an awesome job on the 2 AWG terminals. I put it on the floor and use significant weight to push the handle home. I also cut the starter cable, but haven’t decided exactly how I’m going to route it–probably along the right side of the engine inside of the intake tubes.

The primary task for the night was to make a mount for the throttle quadrant cables. The cable housing needs to be secured so I made a bracket out of some spare angle I had. 0.125″ probably would have been good enough, but all I could find of the right length was some 0.189″ thick angle. The nuts on the cable are too large to line them all up, so I staggered them. Lots of cutting on the band saw, belt sanding, Scotch-briting, and drilling. It looks pretty good.

I mounted the quadrant to the panel and subpanel to figure out where to attach the mount. I discovered that the throttle cable is a wee bit short of perfect. Since the 51″ mixture cable is plenty long, I started swapping it with the 50″ throttle cable. Hopefully that will be enough extra. I knew I’d be messing with those cables again. While they’re off, I’m going to make a better positioned mount for the other end of the throttle cable.

I drilled another set of holes to secure the SL-40 tray to the subpanel. There wasn’t a hole in the right place on the tray, so I just made one. That’ll make everything more secure.

I also did some work on the shopping list for wiring. I need some 6 AWG cable for the alternator and fuse blocks, and the associated lugs, and some switches, etc. Placed orders with B&C and SteinAir. I would have just ordered everything from B&C, but Stein has much better prices on some items. Unfortunately, Stein didn’t carry everything I needed.

Feels like I’m in the middle of 30 different things, but I’m definitely making forward progress.

I started prepping for installing the panel by mounting the avionics trays to the panel and then mounting the connectors and wires onto the trays. The big pile of spaghetti wire looks a lot better when it’s installed. Mounting the connectors was very easy on some trays–well, actually all the trays except for the SL-40. That thing is a PITA. The holes in the tray didn’t line up with the connector housing and you’re trying to install tiny screws at the back of a very narrow and long tray. I ended up drilling out the outer holes to #30 and still had to do some filing. I probably spent half an hour on that one tray and 10 minutes on the others combined.

With Julie’s help guiding the wiring through the subpanel, I mounted the panel into place on the fuselage. We ran into one minor snag. I didn’t make the cutout for the audio panel wiring quite big enough. I’ll have to remove the panel again and go at the subpanel with the Dremel. Before doing that, I trial fitted the quadrant mount. I still have a few holes to drill there and installing a chunk of angle for holding the control cables will be easier without the trays in the way.

Overall it’s looking great. This is the really fun part–putting the panel together after months and month of planning.

This is the kind of riveting I do not like. Lots of very limited access and difficult angles. I started out trying to use the squeezer, but it was one rivet with this yoke and then one rivet with that yoke and then switch rivet sets, etc. I just went for it with the 3X gun. Much easier, but still not fun with the garage near 80 degrees and me in ear muffs. The rivets on the F-902 right under the canopy deck are particularly unfun. The subpanel structure is mostly riveted in at this point. I can’t wait to get the panel in and start fitting everything together and wiring it up.