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harness attachment hardware

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Well-Known Member
Sep 15, 2006
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I am re-working our harness attachments and have some options for which hardware to use.

A lap belt has oversize 5/16" holes in the end of it. I figure it is best that the belt hardware has a loose fit so the belt is free to swivel about somewhat. In the construction of these attachments on the fuse I will need mounts with bushings in them. We could:

1) Use a 7/16" X .065 bushing with a 5/16" clevis pin, AN 960 washer and cotter pin in it.
2) Use the same bushing with an AN5 drilled bolt, AN960 washer and castle nut with cotter pin. The bolt would have to be left as a loose fit.
3) Use a 3/8" X .058 bushing with an AN4 bolt, 5/16" X .035 X .25" bushing (reamed), AN 960 washer and an AN365 nut or castle nut with cotter pin bolted snug. The lap belt end would have the small bushing inside.

For comparison sake, our Cub has a sloppy AN3 bolt with an AN 365 nut- loose fit. I have been wanting to change that.

Is there anything wrong with a clevis pin in this application? That would be the simplest approach. I have mixed feelings about leaving an AN5 bolt loose even with a castle nut and cotter pin on it. I have been thinking the lap belts on an aerobatic airplane warrant at least 1/4" fasteners. That's why I didn't consider AN3 hardware.

Any thoughts?



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