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20. Extend the lines along the cowling´s back edge which were drawn in step 9). More
lines should be added for later better orientation/accuracy (Figure 16-005).
21. Trace the back edge of the cowling onto the fuselage (Figure 16-005). This helps to
determine the new length of the cowling´s and the amount of material that needs to be
removed.
22. Using vernier tool transfer the distance traced from the fuselage to the cowling´s.
Make sure you do this for each line accordingly (Figure: 16-006).
23. Remove the cowling´s from the fuselage and connect all the marked points on the with
insulating self-adhesive tape (Figure 16-006) and remove the appropriate amount of
material using dremel tool (Figure 16-006).
Figure: 16-006: Marking the cowlings cut.
24. Install the cowling´s back on the fuselage front end and use a pen to mark the 1-2 mm
gap between the cowling´s and the fuselage. Then remove the cowling and grind it
down with sandpaper.
NOTE
: The key is not the gap size but that the gap is equal along the cowling-fuselage interface.
Make sure you repeat step 22) as many times as needed, do not rush this step.
25. Temporary tape the cowling´s to the fuselage with masking tape and repeat the step
9), Extend the lines marked on the fuselage (just those which coincide with inserts) so
they are visible on the tape you have run around the cowling-fuselage interface.
26. Marked points on the drawn lines 30 mm into the cowling. Those new points should
coincide with the center of the insert under the cowling.
27. Use a hand drill with a Ø2 mm drill bit and drill a hole at every lately marked point. On
both sides find the second inserts below the cowling halfway seam. Measure 110 mm
downwards and 12 mm (Figure 16-001 Blue marking) in the direction of flight. Drill a
Ø3 mm hole through the cowling and the fuselage´s rim. Determine the last hole
location using the same procedure.
28. Remove the cowlings and widen all the holes along the upper cowling with Ø6.2 drill
bit and all the holes along the lower cowling with a Ø4 drill bit.
29. Fit the quick connect bolts with star washers to the upper cowling. Fabricate a slotted
tool similar to the one seen in Figure 16-007. Slide the quick connect bolt through the
hole and secure it in place with star washer. The fabricated slotted tool allows you to
