Category Archives: Seats and Upholstery

Iterate and Repeat

It’s important to keep making progress and not get bogged down on any one thing – like wingtips. Oh those wingtips! Will they ever be done?

Parachute, flaps, ailerons, seats, control sticks were all calling for attention. It was well worth spending time on to those things. Circle back to composite work later.

Much of the work is pretty straightforward. Other items require a bit of faith and commitment – like finalizing the riveting of ailerons and flaps closed, for example. Getting the control surfaces locked down with rivets and while maintaining alignment with the wing, is both science and art. I think maybe there’s a good bit of luck involved too.

Chopping off the control sticks is somewhat a leap of faith. The KAI doesn’t say to do that, but the Tosten CS-8 grips need to be in the right spot. They’re different than the push-on type that is typical for Sling 2s. You just gotta do what you gotta do.

Figuring out what to do with the parachute cables has been an exercise. There is almost no guidance from the factory. I asked them directly and they admitted that the factory rarely installs parachutes in Sling 2s they build there, and haven’t for a long time. There’s an old video. I’ve watched it repeatedly.

The one actual attempted in-flight deployment of a parachute-equipped Sling 2, ended in failure – loss of the aircraft. Fortunately, that was during factory testing and the pilots had their own parachutes – which they needed. That sad outcome reportedly resulted in consultation with the Stratos 07 parachute company. Changes were made and presumably incorporated in my kit. It is, nevertheless, clear to me that a builder could easily insure a complete tangle of the parachute and cables during a deployment. I’ve studied photos of several other Sling 2 parachute installations and identified things I thought could be problematic. I’ve tried dress and secure the cables to allow the best fighting chance for the parachute canopy, shrouds and airframe-cables to deploy without hindrance or entanglement. My guess is probably as good as anybody’s. Maybe better.

The weather is getting rather nice. Competing interests punctuate my days.

CF – Upholstery, Painting & Wiring

Upholstery work takes a bit of courage and determination – at least for me it does. A big part of the work involves trimming the vinyl leatherette-like covering to fit the center console and then bonding pieces of material to some rather sizable and awkwardly shaped panels – everything is frighteningly sticky with spray adhesive.

I got through it and it all seems to look rather nice. I can’t say I’d do it the same way again, but at the same time, I don’t exactly know what I’d have done differently. You’ve just got to do the best you can.

All of the center upholstery pieces came in a kit, along with fiberglass-backed side panels, seat and seat back cushions, and carpet panels for the floor and luggage compartment. The seats cushions are covered with genuine leather and stitched by professionals. I got to choose the colors. Methinks it’s going to be a rather sporty and plush setup for this little 2-seater. Oh well! What can I say?

Once the rear portion of the center console was covered, it seemed a good time to put it into position. The inside seatbelts pass through, so it was time to assemble those to their anchors. I haven’t riveted the rear console yet – just clecos for now.

The front console panels have 3 sections. The top panel of the LH side is removable for inspections, as are 4 other square panels – 2 of which are covered with the vinyl. The 2 forward most panels are painted, along with 2 panels for the baggage area.

Bonding the covering to the RH side panel was the biggest challenge. The section of material was large enough to be unwieldy. Working conditions inside the CF were awkward. I did, however, manage to lay in the material and get it satisfactorily positioned. I’m happy to have that task in my rearview mirror.

This seemed a good time to complete more of the wire connections to the rear fuselage (RF) section for the tail beacon and electric pitch trim servo. The PVC jacketed wires in the RF were routed and secured as part of the factory quick-build (QB). My custom avionics harness was provided with “pigtail” connectors. I connected the wires of the pigtail to the fuselage wires with Raychem D-436 series butt splice connectors. The connectors are a bit expensive and a special crimp tool is required. I believe the resulting connections are more than satisfactory. As usual, I insulate and protect the connections and secure them from movement.

Seat Assembly

Assembly of the adjustable seats has been straightforward. They’re made up of 2 hinged panels that have a simple channel structure, sandwiched with identical skins – top and bottom. Inside the seat base is spring-loaded lever and cable mechanism for the slide locking pins. I opted to adapt some clevis pins instead of using the kit-supplied (large) solid rivets to assemble the linkages. The rivets proved difficult to deal with. It took a few days of pondering, but I eventually realized that custom fabrication of clevis pins were the way for me to go.

The only metal preparation I did was deburring and scuffing with a Scotch-Brite pad. I may or may not paint the seats as they’ll be almost entirely covered by the upholstery. The structures and panels fit perfectly and went together quickly. Sling 2 seat design has apparently changed over the years. The recently manufactured parts I had didn’t exactly match the construction manual, but understanding and dealing the differences was not difficult.

There are now at least 2 ways that the piano hinge can be mounted between the seat base and back, so that it can folded forward to access the luggage compartment area. The deciding factor seems to be how far beyond perpendicular to the seat base the seat back will naturally recline. The construction manual shows the hinge on the surfaces, riveted across step transitions where the side channels overlap the skins. The hinge, mounted to the back and bottom edges of the seat panels just seems more appropriate and allows for about 21 degrees backward and no restriction (until the panels meet) in the forward folding direction. That’s perfect. Seat recline angle is set by side-straps anchored to brackets at the edges of the seat panels.

The seats slide on rails mounted to the center fuselage. Clearances are pretty close, but appear to be perfectly aligned. Finding that helps to confirm that the center fuselage is built straight and square. Oh let me tell you that’s good news!