Just thought I’d share this incase someone else is looking for options on how to replace control horns that have been epoxied into a foam core wing
The flap control horns on my Alpina are too short (I suspect), amplifying minor slop including servo gear train slop, definitely increasing load on the flap servo in the flaps-up position (lots of buzzing that disappears as soon as lightly support the flap from below with my finger, and finally opening the door to flutter.
I’ve been wanting to replace the horns with longer ones, but how? The horns are circuit board material firmly epoxied into a full depth slot in the foam/obechi/glassed flap.
I was about to go simple and just cut the horns off flush and then screw in some old school Robart horns complete with unsightly screw plate on the back side (too) of the flap. Easy!
No,, yuck! - I decided to try to excavate the buried portion of the old horn with my Dremel. I was positive this would be difficult forcing me to fall back on the Robart horns.
The diameter of this tiny Dremel bit (including the shaft) is about the same thickness of the control horn. To my surprise it was not difficult to control the bit and excavate the buried horn without the bit wandering or driving itself off the narrow edge of the horn and diving into the soft foam on either side.
The flap control horns on my Alpina are too short (I suspect), amplifying minor slop including servo gear train slop, definitely increasing load on the flap servo in the flaps-up position (lots of buzzing that disappears as soon as lightly support the flap from below with my finger, and finally opening the door to flutter.
I’ve been wanting to replace the horns with longer ones, but how? The horns are circuit board material firmly epoxied into a full depth slot in the foam/obechi/glassed flap.
I was about to go simple and just cut the horns off flush and then screw in some old school Robart horns complete with unsightly screw plate on the back side (too) of the flap. Easy!
No,, yuck! - I decided to try to excavate the buried portion of the old horn with my Dremel. I was positive this would be difficult forcing me to fall back on the Robart horns.
The diameter of this tiny Dremel bit (including the shaft) is about the same thickness of the control horn. To my surprise it was not difficult to control the bit and excavate the buried horn without the bit wandering or driving itself off the narrow edge of the horn and diving into the soft foam on either side.
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