Mr. TS & The Temperature Humidity Meter

All the heroes in this universe run into meters rather sooner than later. This time Mr. TS (Or Table Saw for those who are not friends) has a run in with one. He helps getting two moving coil meters out of retirement and back into active service as temperature and humidity weather station for indoor use.

These two old meters are soon to experience a serious change of venue. It turns out however the milli amp meter on the left is too rusty to get back to service. After inspection and multiple attempts to resuscitate it, it is sent to meter heaven with a proper farewell party…

The meter is dead. Long live the meter! Or so it went in ancient history. The new meter is in need of some TLC for it’s broken glass. The glass from the previous dead meter is (almost) the perfect transplant! Not a complete farewell after all. A glass cutter makes short work of the main shaping.

Ms Dremel finishes up the job with a grinding wheel. A perfect fit!. Next, back to HQ to scan the (original) plates. Some GIMP magic later, the original meters scales are converted to a Temperature and humidity scale. See GitHub repo for the gimp files. The printer at HQ soon spit out a paper version of these!

Mr. Screwdriver pokes a few holes in the paper at the point where the screws normally would go. Adding the screws in from the side and flipping the hole plate makes an easy job of aligning the new paper scales during glueing operations. 3M Photo Mount makes it a sticky business, but one should last!

The two rejuvenated meters are now both eager to start a new job. A new live even! An Arduino Nano puts them through training school. On a breadboard with two trimmer pots to calibrate the meters plus a DHT22 Temperature and Humidity sensor.

After testing the meters earned their tenure! The tenure comes in the form of a perf board with the sensors, trimpots and Arduino Nano. The code is on GitHub: . Here is a video of the calibration: Now all they need is somewhere to live. But fear not, Mr. TS comes to the rescue!

Mr. TS quickly cuts up some pine board, and with the help of trusty side clamps these are glued together. Looking at their new house being constructed, the meters take a nap whilst the glue dries.

The meters wake up to a shiny pine box. They find it a tad boring however to spend the rest of their lives in, so they consult with Mr. TS. No worry fools! says TS, I will fix you up. Using his trusty sidekick the spline jig he creates cuts all around the box. He got this idea from a youtube video by Jon Peters – Longview Woodworking:

Adding some darker wooden insert, cutting sanding and assembly and our adventure comes to a brisk end!

The End