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Stiff and light pushrod from balsa.

After some bad experience in previous years I prefer to make pushrods (mainly for elevator) from the same material as the fuselage.  My bad experience was with carbon-pushrods in balsa fuselages, different expansion coefficients lead to constant trim-change with changing temperature.  So in balsa fuselages I prefer a balsa pushrod. Of course one could use a 10x10mm square of balsa as a pushrod.  The problem with that is that a 10x10 is not very stiff, and it's not always easy to find one that is straight.  So .... the task is to make a square tube of balsa-sheets. The one I made recently was from 2.5mm balsa and with 8x8 internal dimensions. The pictures with comments should tell it all.  The main problem with the pushrod shown below, is that it's very low-tech: no carbon-fiber, no ball bearings, no pink aluminum parts.  In spite of this it becomes light, strong, accurate etc ! Hmmm ...  where is this all going to end ? 

Start by making two ends of the 8x8, and some small stub's to help keeping the shape of the tube. Glue them along one edge of a strip cut from the balsa-sheet.  The strips must be straight and slightly wider than 8 + the thickness of the sheet. 
Add a second strip of balsa on the side that was 'overhung' by the first strip.  Keep it flat on the building surface when gluing to keep it all straight. (you workbench is straight isn't it ?).
Continue with the third strip, use thin CA and it's really fast.

The last strip is in place, sand the sides flat and you almost done.



The steel pushrods at both ends are fixed the old fashion way ; drill a hole, bend the end of it, insert into hole, wrap it all with sewing thread and apply thin CA to finish it of.