Canopy Frame - Part 2

With the starboard side fixed the port side was still a moving feast so this was the next major task.

The factory had advised me that it would be better to fit the spreader shown on the plans at the center not the rear but as the canopy was cycled with the single spreader it was clear that on this aircraft both would be required so it was decided to add a additional one at the center.

Center Spreader

Attachment

The spreader was fabricated from a piece of 40 x 12 x 1.6 mm 2020 aluminium extrusion that was on hand. 

This was cut to size 8 mm undersized and then a series of 20 mm holes pitched at 38 mm centers were drilled along it's center.

A pair of attachment angles was next fabricated from 0.030 2024-T3 aluminium and then all items were primed for assembly.

The frame was taped into position and aligned with the reference mark and this is critical, if not done the spreaders will be in the wrong position.

Center spreader installed.
Gray marks are epoxy metal filler from a incorrect installation

The 60 mm position is a minimum distance and any closer the bar will foul on the roll bar when flipped over.

Rear Spreader
The attachment angles were re-fabricated to allow the spreader to align with the face of the baggage compartment after begin relocated from the center. The actual angles are a compound of various facets so a 40 wide angle was fabricated from 0.040'' 2024-T3 aluminium and clamped into the frame as shown.

Setup

The spreader was leveled with a digital  level using the top side of the wheel well as a zero reference. The top side of the spreader was then marked and the angle removed.

With the angle on the bench a tab was cut to fit to the inside face of the spreader , then the assembly was reinstalled as shown and the spreader centered with the two mounting holes transferred to the tab.

This was removed again trimmed and pop riveted. Finally the opposite side was now trimmed and the mounting holes drilled.

Attachment tab - both side

Installation
Alignment of the mounting holes was the next issue as with a little extra pressure it would move with no control. 

Reference lines

A series of reference lines were added to the side of the canopy frame using the baggage compartment as the datum. 

The spreader was installed and clamped into it final position using these line's for alignment. 

Once satisfied one hole was drilled, clecoed, repeated on the opposite side. A final check, tweak and the other pair were drilled, then all pop were riveted using 3.2 x 8 mm rivets supplied with the kit.

Finished Spreaders