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I started the gear cover per
plans with duct tape on the recess and pieces of PVC cut and fitted to make
up the basic overall shape. I epoxied some extra layers of 3/8" PVC on
the ends, on the inside, to make it easier to shape the gear cover (on the
sides near where the gear legs come out) without having to bend the foam. |
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Another shot of the gear cover
when still in foam blank state. |
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Here's a closer shot of the
layers of 3/8" PVC I used to make up the brake. In hind sight, I wished I
had made this out of thicker foam, but hey, I had the 3/8" laying around and
I would have had to wait if I had ordered thicker foam from Wicks. |
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I used my router with a
roundover bit to round the edges of the foam for later when I have to do a
layup on the inside of the brake. |
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My Stanley Shurform plane works
great for shaping foam parts like this. Some foams are real easy to
sand and not bother with carving, but PVC is sort of rubbery and the plane
does a good job of it, and quicker, too. |
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Here's the gear cover after
installing the outside layups. Not too big of a deal, although the
corners on the inside of the NACA scoop were pretty tricky. |
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Installing the boards on top of
the gear cover. Again I used hot melt. Quicker and less stinky
as compared to bondo. |
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Here's the gear cover after
sanding all the sharp corners round. You can see the micro stripes
that revealed themselves after sanding the inside to shape. I used the
micro to join the extra layers of foam. |
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To get a pretty nice edge on
the gear cover around the gear legs, I used a contour gage. I know
that this intersection gets a fairing later, but, I wanted to make the edges
pretty decent anyway. |
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Here's the intersection of the
gear cover and gear legs after final contouring. It's a pretty small
gap but it's on the underside of the gear so any hard landing-induced
flexing of the main gear legs should move the gear away from the gear cover,
not toward it. As I write this though I realize I may need more room
on the other side - the side between the fuselage and the gear leg - for
just that reason. |
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Cling wrap installed in the
hole in preparation for the inside layup of the gear cover. I used the
wide stuff and therefore didn't have to piecemeal this together out of
smaller sheets. Don't use stiffer plastic, the cling wrap will need to
stretch a bit over all those awkward corners and shapes to enable the gear
cover to fit into place properly. |
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Given the gear cover is
non-structural, I decided to use up some fiberglass scraps to make it.
If you do this sort of thing right, you can't see that the layup is not made
up from one piece of BID per layer. Sure, the purists out there say
just buy more glass, but I can't resist being frugal on non-structural
parts. |
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Here's the strips of wetted out
glass for the edges of the gear cover. This is where I used the scraps
mentioned above. These sort of strips have a tendency to pull apart
more easily when made from scraps, of course, but if you make them on wax
paper or plastic that's a trivial issue when you install them on the part. |
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Gear cover, inside layup
complete, installed over the cling wrap and weighted down in place.
Wait 24 hours and we'll have a gear cover! |
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After the inside layup cured,
it was time to drill holes for the aluminum inserts. No mystery here,
mark, check your dimensions, then drill and hope for the best. |
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Here's a close up of the gear
cover, marked and ready for drilling. The MGS epoxy makes a layup that
is fairly clear so finding the exact location of the inserts is pretty easy.
I still used a square and a ruler to find the exact center of them, however. |
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Drilling the aluminum inserts
for the gear cover screws. |
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I had one insert that was
fairly close to the edge of the bulkhead it was mounted in. To prevent
the tap from cracking the insert, breaking the glass or something else bad,
I clamped a piece of aluminum against the insert then tapped it. It
worked well and I was able to tap the insert without causing any other
damage. |
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After drilling and tapping the
holes in the inserts, drilling and counter-sinking the holes in the gear
cover, I installed the cover once with all its screws. Really cleans
up the bottom of the airplane, doesn't it. |
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One final shot of the bottom of
the plane with the gear cover installed. I think this setup has a lot
less drag than with the gear cover not installed! |
| The landing gear cover is now complete. Axles and brakes are next, but I've only just
started on those - click here for that page. The landing brake
I have started on
click here. |