Sunday, December 25, 2011

A Fitting Result

It's just after 8:30 am Christmas morning and, very unlike the years when Co-pilot Egg couldn't sleep because she was so wound up over the thought of a passel of gifts under the tree, I am the only one up. Even the dogs who, in the vernacular of the household have "been and had" (been outside, had their morning Milkbones), are curled up and sleeping.

There are no presents under the tree for me, what with my having started utilizing my new K-cup coffee maker more than a month ago, but I still eagerly await the gift opening. I'm not sure why; it's not as if young Egg will be surprised by anything. The only thing we got for her that we thought would be completely unexpected is a new set of beads to hang in front of her bedroom door (her only nod to any form of impending teenage hippy-tude) which she correctly guessed within two seconds of picking up and shaking the wrapped package. Why she can't be that deeply intuitive about something important like, say, statistics is beyond me.

The CEO of Schmetterling Aviation will be visiting today, along with the corporate office's CFO and it is always nice to have progress to show on The Project. I thought having the Shroud of Culin fitted and mounted would be, well, a fitting tribute.

But first.... I had to excise the superfluous grounding lug from the starter motor. I had spent a little time wondering if the removal of the lug was one of those silly weight saving things Van's does now and then, but those are typically called out as being optional. This job was not. I finally realized that the lug has to go because it might interfere with the fit of the motor mount. I'll find out for sure soon enough, but for now it doesn't really matter. Van's says "amputate," I say "Gimme a saw."

Or, as in this case, "Where's that Dremel?"

The cutting disk on the Dremel wasn't beefy enough to do it in one cut; I ended up making multiple passes at it, each pass cutting slightly deeper than the one before. When the trench got too deep for the ever-decreasing diameter of the apparently ablative cutting disk, I resorted to finishing it off with a hacksaw.

The starting step of fitting the Shroud of Culin (just in case you still don't get the pun, read here) is to mark it in a way that will show that the fitting is done.

This process involves two disjointed hands. Well, it requires three, actually, but two is what I have.

The horizontal line on the top is the measurement line. When the shroud is correctly fitted, it will be flush with the top fins of the cylinders. The line inside is traced along the almost invisible scribe lines molded into the shroud. No mention is made of them in the plans, but I thought that it might be helpful to see where they are, just in case they might end up being useful.

I took a swag at where the first cuts should be.

After the first cut, it was apparent that I'd have to do a lot more cutting. In fact, it looked like the scribe lines might be a useful place to start.

I didn't go straight to the scribe lines, but after a few tentative approaches I found that the scribe lines were pretty accurate. There were a few spots where the lines didn't show - for those I used trial and error. Quite a few times, as it turns out. Test positioning the shroud on the engine before I got the trimming done resulted in the shroud getting well and truly stuck in place more than a few times. Eventually, though, I got it to fit.

There was one corner of the raw, unmolested shroud that was just resin with no underlying fiberglass. I managed to cut too deeply into that area (without the cloth, it looked like an area that should be cut out) and it will need to be repaired. The tolerance provided in the plans only allows for a 3/16" gap and I created one that's more like a half inch. I need to mix up another batch of epoxy for another smoothing coat on the canopy, so I'll just add a little piece of fiberglass cloth back over the spot that I cut too deeply. That's the thing about fiberglass: you can always add some back!

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