| Began assembly of the Upper Fwd Fuse, in itself it's relatively simple, however the 3 ribs in the structure are placed so as to |
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| make it difficult to install too much in the way of avionics. Several builders have made modifications, and here's where the time |
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| today went. I tried some of the mods which were basically Alum angle that is cut on the vertical axis and then the horizontal axis |
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| is bent to provide the clearance. I found 2 problems, 1. there is little strength vertically in the event of a |
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| compression/decompression event, the horizontal portion of the angle provided good latteral ridgity, but I worried about the |
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| vertical. 2, the 6061 seems to be brittle, and when bent to the degree necessary, it would develope cracks, further weakening the |
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| 'fix' I came up with my own approach which was to take some surepluss wing skins damaged in shipping, and cut 4 thicknesses |
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| of 'doublers', this coupled with the existing ribs should provide the vertical rigidity. then I criss-crossed some alum angle with the |
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| flanges pointing in opposite directions, This provides the horizontal rigidty and eliminates the problem of weakness where the |
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| cuts were made in the other mods. (see pictures). I got the stiffiner for one rib made and will duplicate it for the other tomorrow. I |
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| may possible do all three as this seems to be a VERY solid means of cutting the ribs back while not weakening them at all. |
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