Locating the Oil Cooler

While I was thinking about the aileron control cables, I realized that my previous location for headset jacks wasn’t going to work. I cut the old bracket off and this is what was left:

Headset Bracket Weld Bead

Headset Bracket Weld Bead


I used the die grinder and files to clean off the weld bead. It’s always frustrating when I end up making more work for myself, but such is the nature of building my own airplane I guess. I picked up where I left off last week with the landing light bracket, which involved using the rotary file in the dremel to finish enlarging the center hole. This is what I ended up with (after a few attempts to get the diameter correct on the back bracket hole)
Landing Light Sandwich

Landing Light Sandwich


The idea is that there is just enough thickness in the LED unit to allow for a tight hold when I attach the front bracket with screws. I’ll need to figure out a way to attach this contraption to the nose bowl, preferably in a way that still allows for some aiming adjustment later on.
At this point I have enough of the cowling done to be able to trim the baffles to their final height. I had previously rough-cut them so that they weren’t touching the cowl metal, so all that I needed to do was make a mark where I wanted to cut. To make that line, I poked a small hole about 1.5 inches from the end of a hotel room key. Any sort of plastic would do the job just as well, it’s just that I have a pile of hotel keys available. I stuck the point of a marker in the hole, then ran the edge of the card along the inside of the cowl metal. Some of the lines ended up on the front of the baffles, and some on the back.
Marking the Baffles

Marking the Baffles


Marking the Baffles continued

Marking the Baffles continued


I trimmed the left side so that I could know where I would be able to put the oil cooler. Tabitha came out later in the afternoon to make more window plans. She laid out the new shape in the upper left window and we worked together to cut it out.
Window Thoughts

Tabitha is thinking, looking at the old window shape. In this shape, the plexiglas is layered between the skin and a backing strip. We’re going to change the configuration to put the plexiglas between the steel frame and the aluminum skin, which saves a bunch of fasteners and allows us to enlarge the window a bit.


Bearhawk Front Window Skin

Trimming around the lock mount on the front window


While she worked on that I marked where the oil cooler will go.
Back left baffle Lycoming 360 oil cooler

First, here are the mounting holes.


Marks

Then I made marks for where the opening will be.


Note! This oil cooler mounting strategy proved to be inadequate in flight testing. The oil cooler is probably a little bit too small for this engine, but more importantly, it should probably be located back away from that cylinder a little. In the end I fabricated a mounting system that moves the cooler back about one inch. Also note that the ideal arrangement would be with the oil flow vertical. The vertical arrangement would give an outlet for trapped air to flow out of the cooler.
Then I cut out the hole for the opening.

Then I cut out the hole for the opening.


Cowl Hinge

Tabitha picked up where she left off on the cowl door hinge, exchanging clecos for rivets.


We’re both motivated to keep the project moving along.

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Hours Logged This Session: 7.3
Total Hours: 1883.75