For the last couple days, I did all the prep-work to install the Skybolt Z-Loc Cowling Fastening System. Before I installed the Z-Loc fasteners, VAN’s original instructions for the hinge-pins stated I needed to install a ½ inch spacer strip onto the firewall-flange to accommodate the thickness of the cowlings. As it turns out, VAN’s didn’t update their plans after they started building the “new in 2006” pink cowlings which are supposedly stronger and are the correct thickness without the spacers. After thinking about this, I decided to install the spacers anyway to reinforce the cowlings with 2-3 layers of 2-inch fiberglass cloth to reinforce the cowlings where the Z-Loc Fasteners attach. I don’t think I will have any “cowling-bulging” inflight due to increased air pressure flowing through the cowling; however, if I reinforce the cowling where they attach using Z-Loc fasteners, I’m sure I won’t have this issue. Additionally, the Z-Loc fasteners are designed to accommodate various cowling thicknesses. It took 4 hours to match-drill the spacers to the firewall flange and another 5 hours to match-drill the Z-Loc fasteners. I didn’t install a Z-Loc where the upper and lower cowlings come together (horizontally) and will do this later, just in case I change my mind to install the Z-Loc’s to attach the upper and lower cowls. I will be able to install this Z-Loc fastener after the engine is installed and make micro-alignment adjustments vertically, in case I don’t have the correct cut-line measurement for the two cowlings.
