Appendix E: Blade deflection test
The following test procedure was developed by mechanical engineering
students Rich Harrison, Ben Hicks, Matthew Lewis and Marc Brinkmann and
their supervisor Dr Mike Clifford of The University of Nottingham, UK.
This test requires some accurate, preferably electronic scales. The scales
used here could change the display so as to show the force exerted in
Newtons, as opposed to a weight in grams or kilograms. Ensure that the top
doesn't move vertically when a force is applied to it, or else the results will not
be valid.
1. Make the jig for the scales, similar to the set-up shown in the below
diagrams and photos. No dimensions have been added, as they can
vary, ensuring that the top plate is sufficiently larger than the scales so
that the scales are not in contact with the threaded bolts. The top plate
rests on top of four nuts, which can be adjusted along the length of the
threaded rod to adjust its overall height. Care to be taken in ensuring
the plate is flat, or close to flat for all measurements.
A schematic image of the test rig
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