Chapter 8 - Step 1

Step 1 involves cutting out and assemplying the headrests and shoulder support.

Head Rest Parts June 19, 2000. I pieced all the parts together from scrap foam. I was able to save buying the 3/8" PVC for chapter 8 (about $17). Here are all the head rest pieces prior to glassing.

Shoulder Support Parts June 19, 2000. I also glued a few scraps together to make the shoulder support pieces.

Shoulder Support Test Fit June 19, 2000. Here is the shoulder support being test fit in place. In addition to cutting the notches out to fit around the longeron, I had the additional task of dealing with the fact that my seatback has a warp in it. I couldn't simply make a 45° bevel on each end. My bevel had to be on a curve as well. It took some extra time but the fit came out great.

Front of Head Rests June 24, 2000. The front face of the two head rests after gluing them together with 5 minute epoxy.

Rear of Head Rests June 24, 2000. The rear face of the head rests. Note the pilot's headrest has no back but it has a bottom. The passenger's headrest has a back but no bottom.

Shoulder Mounts June 24, 2000. Here are the two halves of the shoulder support after adding the four plywood hard points for the shoulder harnesses. Next to each is a nut plate.

I made a modification here. My attach points are 11.5" center to center instead of 8.6". The original dimension was 11.5". Back in 1995 Nat made a mod down to 8.6" based on a report by Uli Wolter - the European Cozy designer. The concern was the possibility of the shoulder harnesses spreading enough to allow the person to slip through during some form of rapid decelaration (crash). Since I am using the recommened harness with an H-strap, there is no way for this to happen. Given all this I decided to go with the original 11.5" spacing. This has two advantages - 1) Better comfort - the closer spacing meant the straps rubbed on my neck, 2) No need to notch the headrests.

Nutplate June 24, 2000. Here is a close-up of the plywood insert and the nutplate that will be attached to it eventually. The four holes will give the flox something to hold onto. There is a 1/4" hole in the center for the bolt to reach the nutplate.