Besides playing with kids... Incl. the snap together electronics game _Snap Circuits_... (highly recommended)
One thing was that I bought a super duper nice toolbox for my older kid (craigslist). He is awed by it and I think that it will serve him well, especially when he grows up. It has four pull out drawers and a big top compartment. We put it on casters so that he can move it around.
Another was putting an hourmeter on the compressor motor. Now I know how many hours it actually pumped air. I'd like to know the ballpark for oil changes in a splash lubricated compressor, in terms of run hours. Any ideas?
The last thing was making a whole house phone switch. A little switch in a black box on the living room wall turns off all land lines. It is very handy because phone calls wake up kids and even ourselves when we want to have a nap. No more annoyance. We had too many land lines to switch off by hand (and those "smart" phones start making annoying sounds when they are switched off)
In both of the last instances, I used little black rectangular ABS plastic enclosures made by Serpac, from McMaster. Highly recommended.
Not really an accomplishment, but I scrapped 520 lbs of worthless electric motors and I am quite happy about it.
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