Front Top Skin Part 1

We spend the day working on fitting the top front skin. Last weekend we went to Friedrichshafen Aero Expo 2022 and met our partner Frisian Air there. This was the first time we saw a completed Sling TSi so we took this opportunity to ask many questions to the builders and to take a look at how the plane was built. Here we saw that they tucked the front top skin inside the side skins instead of mounting it over the side skins. We really liked how this looked so we decided to do the same.

We mainly focused on these things when looking for the right fitment:

1. top skin flush with the fuselage skin / firewall flanges at the front
2. split between cowling fastener strips on firewall to be in the middle of the two dimples in the front top skin
3. the alignment of the top skin with the holes in the fuselage skins. We marked 10 mm off the edge on the top skin for the side skin holes, and we inserted the front top rib flanges about 5 mm inward from the top skin edge (part below dashboard)
4. buckling of the composite/aluminum
5. gaps between the aluminum skins and composite front top skin
6. narrow part of the front top skin flush with the canopy (we had to trim off a little)

We used a ratchet and strap and glue clamps to hold the front top skin in the correct position. We drilled all holes to 3.2 mm in the front (not covered by skin) using a DIY hole finder and match drilled all holes on the sides to 3.2 mm with the skins.

Because we wanted to tuck the front top skin inside the fuselage skins, we had to dimple the fuselage side skins and firewall flanges and countersink all holes in the front top skin except the ones below the dashboard. For this, we discovered a great new tool called a "microstop countersink cutter with pilot". This prevented us from countersinking to deep and this created nice and circular holes.

Next time, we will glue and rivet the front top skin on.

Builders:

• Pepijn
• Tetsuo