Somebody once said to me “I don’t talk about religion or politics. Why? Because everyone has their own opinion and I’ll just pull the other person into a negative emotional state if we talk about those topics. Thus I have to stay on other subjects, so they associate positive emotions with our interactions.”

Nothing new. However I have to add the topics of :

  1. climate change and
  2. diet / exercise.

Do I have the self discipline to do this?

Time will tell.

New fin prototype CNC milled from MDF.

This prototype fin milled from MDF came out quite well and the customer was happy with the result. This is just a proof of concept at the moment though. The main point was to see that the camber from the fin box could be machined at the right angle.

Also the tip of the foil may look a bit thick. This was intentional as I was just showing consistent proportions of foil shape down the fin. Foil shapes are measured as a percentage of the chord length. The chord being the distance from the leading edge to the trailing edge. Towards the tip of the fin the chord increases and thus the thickness does also. Therefore on this fin the foil is actually proportionately the same all the way down, even though looking from front on it does not look even. This will be changed in the final version.

This fin profile is the customers design.

See vid here


Auto swimming pool PH and chlorine tester

This automatic mechanical PH or chlorine swimming pool water quality tester worked quite well in the lab tests. 3 weeks of work for 2 people lifted the project to an adequate level. There are alternatives out there for chemical testing, but this is a mechanising of a human process.

The process is as follows

  1. The pool water is pumped into the vile,
  2. The testing tablet is then dropped into the vile
  3. The magnetic agitator agitates the solution which changes colour
  4. The light sensor senses the opacity of the solution colour
  5. The vile rotates upside down to empty the solution
  6. The vole is flushed with fresh water
  7. Process is ready for the next test.