Prop Thrust Meter by dmyers7

Last crawled date: 3 years, 1 month ago

4-22-2015 Version 2 is here. See Thing: http://www.thingiverse.com/thing:770637 If you like, please follow the link to the instructables contest and give me a vote. Thank you.
2-28-2015 Version 2 is coming. Modeled after the Turnigy thrust stand, I will be hacking a ordinary kitchen scale for $10 and building a stationary all in one thrust scale that can measure up to 11 lbs of thrust. Check back or simply follow-me and you will see my next posting.
I developed this double arm equal arm balance so that I could measure the amount of thrust any particular motor and prop combo can produce. This way I can tell how heavy my model can be and still stay 3D or maintain flight. All parts are equivalent for the left and right sides so the scale components will not skew (add or subtract from) the measured force. The double arms keep the motor and prop parallel to the measurement plain and the force transfer paddle always flat on the scale. I use a regular kitchen scale to measure the force / amount of weight lifting capability. Add a current meter inline with the battery and you have a pretty nice setup ready to find the best power to thrust combination. I was able to measure on the motor shown that a 6x4 prop produced more thrust than a 6x5.5 prop. For a given torque, exceeding the ideal prop pitch actual reduces the amount of static thrust produced because the motor becomes inefficient.
As aways, please be careful with rotating props. Proceed at your own risk....