Chapter 9 - Step 4

This step involves making the landing gear cover. This is a removable cover that goes over the strut between the two landing gear bulkheads.

Masking Joggles May 28, 2001. The joggles have come back to haunt me some more. I made a big mistake when I made the joggles in the landing gear bulkheads for the landing gear cover. I made the joggles perpendicular to the bulkheads instead of parallel to the fuselage and NACA scoop bottom. In an effort to clean up the joggles so I can more easily build the cover, I decided to "adjust" them with some flox. In the end the cover is 5 plies of BID thick. This is about 1/16". What I will do is create a jig with 7 layers of Duct tape (about 1/16"). I will then press flox into the joggle, put the jig in place and let it dry. When done I will have perfect joggles so I have a neater, better fitting cover.

Joggle Close-up May 28, 2001. Here is a close-up of how bad the joggle is. The entire gap will be filled with flox.

Floxed Joggle May 28, 2001. Here are two small segments that have been floxed, one forward and one aft. My original plan was to have a smaller piece of foam that reached across the gap. This would have two strips of Duct tape. I would flox the whole joggle then press the jig in place to squeeze the flox. Lift it up and press down again a few inches over. This didn't work because when I picked up the jig, much of the flox stuck to it making a mess of the flox in the joggle.

Jigged Joggles May 29, 2001. A few more joggles are being jigged and filled with flox.

Jigged Joggles May 29, 2001. The same jigs from below. If you squint you can see all the flox.

Sculpting the Cover June 2, 2001. Due to the curves involved I decided to make the cover out of Urethane foam. This way I could easily carve a nice shape into it including the curves of the NACA scoop. I didn't even need to add the "shelf" because I managed to get a snug enough fit of the main pieces. You can see the 1/32" of duct tape over the joggles. The foam is being sanded down to the tape.

Finished Foam June 2, 2001. Here is the completed cover before glassing. I am getting nice smooth transitions from the forward landing gear bulkhead to the rear. The NACA scoop has a smooth curve in it too.

Glassing the Scoop June 2, 2001. In preparation for glassing I realized I need to put in something to keep the cover from being permanently glued to the fuselage. I added some cling wrap - nice holiday color. Like the other parts of the NACA scoop I want sharp corners so I am doing the layup in steps. First I am laying up the scoop itself. Later I will make a flox corner and glass the rest of the outside of the cover.

Rough Cover Underside June 7, 2001. After a bit of work I got the cover off of the fuselage. Here is the underside before any sanding and shaping. I Sanded the foam down to about a 3/8" thickness and beveled all the edges so the glass will lay down. I then sanded the edges of the glass straight so it fit nicely in the joggles.

Cover and Strut June 8, 2001. Here is the cover in place over the strut after I finished shaping the cover. It is cool to see all of this in place. I still need to glass the underside of the cover. I have also just floxed the MKMGAs into the strut and it is curing here after verifying the strut position. It appears I managed to get one leading edge at the correct F.S. while the other is about 1/8" too far forward - not too bad.

Cover/Strut Gap June 8, 2001. A close-up of the gap around the cover and the strut. Years from now this will all get covered by a fairing of some sort.

Glassed Cover June 16, 2001. Here is the cover after adding glass to the underside. I only added one layer of BID on the edges instead of two to ensure the thickness wasn't too much.

Mounting Holes June 17, 2001. After the cover dried I marked all the locations for the 16 mounting screws and drilled and tapped the holes. I was 16 for 16 - yahoo. After that I countersunk the holes in the cover for the heads of the screws.

Completed Cover June 17, 2001. The completed cover in place with all the mounting holes finished.