Canopy Trimming

Before I tell you about the trimming of the canopy I'd like to show you some peculiarity about the fit of the canopy on the front bow. Sure it needs some trimming to adjust the gap between the forward canopy edge and the sheet metal covering the avionics. The thing that looks odd is the significant droop of the canopy of the left and right curved area. It appears that it is about 1/8" to 1/4" too far below the surface of the metal reference surface. Not in the center section, only in the curved area.



This area will get covered with fiberglass later but I am concerned that this droop is so deep that I might have problems filling this sufficiently to not show in the fiberglass layup without some serious filling work. I'll have to look at other blogs to see if they had the same kind of fit ...

But on to the actual trimming now. I masked the area to get trimmed with a blue painter tape strip. This made it easy to guestimate the 1/8" gap (which should be at least 1/8" to allow for enough clearance when opening the canopy). All I had to do thereafter was to remove the material that wasn't covered by the tape.
It was a pretty cold day for plexiglass work so I decided to use the space heater to heat up the acrylic a bit.


It was quite a time consuming using that little HF belt sander but the tool is easy to control and the chance to ruin this $1k canopy is quite small. About a third into the work...


... and finally done.


I had to do one additional trim run as the right side didn't show enough clearance but that job was quickly done. After putting the canopy back on and adjusting it, the gap appears to be uniform and large enough.



Now I have to mark the tangent line on the front bow for which I will try to use carbon paper as we used with typewriters. I hope this will work better than the method described in the manual ...