Panel Wiring

Posted on by Neal

Over the course of the last week, I’ve spent time installing the wiring frame between the sub panel and firewall, and the slowly working to zip tie and secure the various wiring bundles onto the frame. Lots of time spent on my back with my head under the panel making slow but steady progress.

There has been plenty of trial and error as I’ve tried to secure the bundles, and simultaneously untangle things. Most the the antenna cables ended up unplugged, re-routed, and then plugged back in again. I experimented with gluing zip tie holders onto the sub panel, but ended up removing most of those, as I found it better to use clamps and/or to secure the zip tie around or through a piece of aluminum. The zip ties are good for keeping the bundles together.

It’s finally starting to look a bit more tidy now.

Panel wiring

Posted on by Neal

Tonight I installed an adel clamp to hold the wiring bundles on the right side of the sub panel. I also worked on safety wiring the various connectors on that same side of the panel. The safety wiring is going to be a challenge for some of the connectors behind the MFD, but I’ll figure something out I’m sure.

Some of the safety wiring visible on a couple of the connectors. I had to redo some of these because I wasn’t happy with the original attempt
Adel clamp to keep the wiring bundle together, keep it away from sharp edges, and provide some strain relief on the connectors

Panel Wiring

Posted on by Neal

The last couple of evening I’ve been using trial and error to work out the right structure to support the wiring behind the sub panel.

One of the changes I’ve made is to rivet together two pieces of channel to reduce the sharp edges.

I also installed an adel clamp bracket on the right side of the subpanel to hold several wiring bundles.

Getting ready to rivet the two halves of the cross beam

Panel Wiring

Posted on by Neal

Tonight I started on the daunting task of trying to tidy up the wiring under and behind the panel. It’s a giant, heavy, ball of spaghetti right now, and I’m not sure if I have enough length to position things where I need them.

I decided I needed some kind of frame behind the subpanel to support the main wiring harness. Using some spare channel, I mocked up a frame and started trying to figure out a solution. I eventually settled on two channels running from the sub panel to the firewall, and a cross beam made from another length of channel. I should be able to rivet the fore/aft channels on the sub-panel end, but not sure I’ll be able to get rivets in on the firewall end.

The scary mess
The basic structure I intend to install

OAT Wiring

Posted on by Neal

Quick job tonight, shortening up the wiring for the outside air temperature probe. Because I installed the probe in the air vent instead of the wing, I was able to shorten up the wiring considerably.

The wiring is a 3-conductor braided cable, and the braided portion of the cable needs to be grounded. I used a solder sleeve with attached wire to quickly solder a ground wire into position. I had plenty of spare pins and connectors, so I was able to install pins on the wires and wrap it up quickly.

The OAT wiring with heat shrink removed, before shortening up the wires

Aft Fuse Wiring

Posted on by Neal

I wasn’t happy with the way the wiring was running through the bottom of the aft fuselage, specifically, the chance of wires chafing on the ship heads of the rivets on the bottom skin.

To fix the issue I wrapped the wiring bundles in a protective layer of braided sleeving. This required removing some zip ties, installing the sleeve and the redoing the zip ties. It came out looking good.

Braided sleeve covering the wiring bundle
Braided sleeve covering wiring bundle

Cowl Fitting

Posted on by Neal

Last night I attempted to address an alignment issue on the right hand air intake. The outside edge was not lined up, so I added several layers of glass on the inside of the top cowl in the area near the prop. Tonight I test-fit the cowl. The good news is that I fixed the alignment issue, the bad news is that I introduced an equivalent alignment issue on the other side. I’m going to leave this for now and come back to the cowling at a later date.

The area on the right side of the pic shows where the layers of glass were added.
The outside edge now aligns well on the right side
The left hand side now has an alignment problem that is approximately the same as what was on the right

Cowl Fitting

Posted on by Neal

Today I cleaned up the excess filler by using a small chisel to gently scrape it away.

With that done I was able to fit both pieces of the cowling in position and confirm everything lined up as expected. It looks good!

Right side of the cowling
Left side of cowling

Bottom Cowl Hinges

Posted on by Neal

Today I riveted on the bottom cowl hinges. The boe-lube worked well as a release agent, and the clecos came out easily. With the hinges glued in place, I cleaned out the excess resin by running a drill through each hole. Before glueing I inserted the hinge pins, just to help avoid any deformation, and I left them in while riveting.

Progress was swift, and I had the hinges done within half an hour. I went to test fit the cowl, but found I couldn’t get the aft edge hinges to line up with the firewall-mounted hinges. Pushing the cowling back caused the cowling to bend outboard instead of seating into position. I took the cowling off, and realized that I had some excess glue between the hinge eyelets on the left hinge. This happened because I used filler to build up a bed of glue behind the hinge where it interferes with the foam section. I’ll try to clean it up tomorrow somehow.

Clecos with blue colored boe-lube as a release agent
Hinge riveting done
The excess filler causing a problem

Bottom Cowl Hinges

Posted on by Neal

After clearing the excess resin, I started riveting the hinges on the bottom cowl. Immediately I realized I needed to first glue the hinges on, not just rivet these. On the aft edges, the interference between the hinge flange and the honeycomb meant that riveting the hinge could cause the rivets to tip, and leave a cavity between hinge flange and cowling. I mixed up some resin and glued all of the hinges into place. As a release agent, I used some Boe-lube on the ends of the clecos holding the hinges.

Left side looking aft
Right side