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Servo Tab Vs Trim? /Epoxy Primer

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Well-Known Member
Nov 13, 2007
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Two questions for the experts. I have the fuselage ready to beadblast and paint with the exception of the trim servo mount. I plan to use the Polyfiber epoxy primer since it has served me well on the Pietenpol parts I have done in the past. Is that suitable as a top coat? In this instance Polyfiber is vauge about things. They clearly say to use it on metal that will be covered with fabric. However they don't specify how suitable it is for areas that are exposed such as the interior of a tube fuselage and they don't offer a topcoat product or mention the need for one that I saw.

The other thing that has me scratching my head is the servotab/ trimtab arrangement where one is supposed to be a trim tab and one servo. By my plans it shows the trim pushrod linked to the arms that are bolted together just above the pushrod. By all reason it seems to me that they would be identical in motion and function. What am I missing?


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