Trim Motor Modification

	The electric elevator trim allows the pilot to trim the airplane to fly 'hands free' at all speeds by changing the angle of the horizontal stabilizer.  As shown in this picture, the piston of the electric trim raises and lowers the leading edge of the horizontal stabilizer.  Some builders of the kitfox have reported that the metal housing of the trim motor has cracked at the bearing hole in the base which could cause a dangerous situation if not discovered during the periodic inspections.
	The first step in reinforcing the metal housing of the trim motor was to manufacture this clamp shown here.  First the block was cut to size, then the hole bored with a lathe, then the bolt holes drilled, then cut in half.
	Next step was to cut and bend the sheet metal sides, even using cardboard templates it took a few tries to get the metal sides perfect.  Before assembly the sheet metal was primed with epoxy primer.
	Here the trim motor reinforcement is shown installed.  The clamp holds tight on the tube with locktite 582 and the bolts.  Sheet metal on each side goes down to the pivot bearing of the trim motor.  The stress on the housing is now taken by the reinforcing brackets so it should not crack but even if it does, the brackets can safely handle the load till the next periodic inspection catches it.

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