Strength testing
I managed to get the use of a fancy piece of equipment that measures the amount of force applied as it pushes down on an object. I set up a small test where a stick was held approximately 20mm above the bead of the machine between two pucks, and applied a force down on the middle of the stick.
There were several goals of this test.
- Create an objective comparitive test between different sticks that didn't involve running them over or hyperactive monkeys
- To see if a stick would bend or break I decided that if a stick bent enough to touch the bed then it was at that point useless as an UWH stick and I would take that measurement as the maximum.
- Compare three different sticks of different materials.
I compared a pine stick with an undercut handle very similar in design to the Stingray, A Stingray and a Dorsal.
Pine stick
This is a pine stick of a similar design to a Stingray. It has an undercut handle and as such has a small cross section where the blade meets the handle. I was very interested in how strong wood really is.
The results of the test show that a wooden stick bends very little and under enough load will snap at a weak or thin point. This stick broke at the intersection of handle and blade under a load of approx 125kg
Stingray - Plastic stick
The Stingray stick is designed with an undercut handle like the wooden stick but it has been accepted that this plastic is not as strong wood. It was hopped that the design of the handle - adding thickness without compromising the ergonomics of an undercut - would add enough strength to make it comparable to wood. What was supprising was that the Stingray didnt break but bent under a similar load to the wooden stick. The stick also returned to flat and returned similar results after re-testing.
The Stingray reached maximum deflection under approx 110kg load
Dorsal - Rubber and plastic stick
The Dorsal is made of a softer, more flexible material but has a much chunkier design and about twice the cross section of the wooden stick and Stingray at its thinest point.
The Dorsal reached maximum deflection under approx 42kg load and sprung back like a rubber band.