Then in June 2024, my propeller finally arrived (an MTV-9-B/198-52):
Propeller sitting on the workbench with the spinner
Propeller hub without spinner
We initially attached the prop, in order to fit the cowling - while I believe it's possible to do that by oneself (at least for a lighter-weight prop like this), it was definitely a lot easier to do with 3 people, both to lift the prop into place, and then have one holding it up while the other two tightened the bolts:
Propeller attached in place
Propeller attached in place
Propeller attached in place, with spinner
When I first test-fit the Showplanes cowling, I realized that it'd require almost no trimming on the sides, and only minimal trimming at the top:
Very small gap between firewall and Showplanes cowl
Sufficient gap between spinner and Showplanes cowl
Finally, in May 2025 we started actually working on the cowling, starting with trimming the top cowl edge to mate with the bottom cowl:
Joining cowl halves after trimming
Match-drilling holes between the cowl halves, as securely as possible
Holes between the cowl halves, clecoed
Turns out the baffles (before trimming) interfere with the cowl positioning (tested via the paper clip method), so I took them off:
Clips on the baffle showing that they're too tall (before trimming) and interfere with the cowl positioning
For spacing the cowl from the spinner, I laser-cut an arc-shaped piece of 3/16" acrylic and used double-sided tape to secure it to the cowl:
Forward end of the cowl with acrylic arc for spacing
We put this aside for quite a while, while we finished other sections - then in June 2026, with the cowling being the only large part left on the build, we resumed, starting with opening the oil door, and re-fitting and aligning both top and bottom cowls:
Top cowl with oil door opening
Top and bottom cowl held in place with tape and straps
After aligning the parts in place and determining centers, we laid out the Skybolt fastener brackets along the firewall flange, starting with the top center 6 brackets, and using the magnet insert from Skybolt, match-drilled the cowl to them:
Skybolt brackets clamped in place on the firewall
Skybolt hole, showing the skybolt positioning adapter
We secured those brackets, and with the top cowl now securable in place, laid out the remaining top cowl brackets:
Primed Skybolt brackets
Remaining top Skybolt brackets clamped in place
The layout required some uneven spacing to avoid the engine mount:
Skybolt bracket positioning to avoid the engine mount top bolt
We then continued to install the brackets, grommets and receptacles for the top cowl:
Most top cowl Skybolt brackets riveted in place
The 15/32" holes for the Skybolt grommets were a bit tight - we only sanded them lightly, then pressed the grommets into place using a clamp with a socket:
Inserting Skybolt grommets using a socket
With this, the top cowl is mostly secured with the Skybolts, except for the very last Skybolts on each side, which we'll position after the top/bottom cowl side edges get trimmed:
Next, we'll do something similar for the bottom cowl.
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