On Highway Noise Barriers, the Science Is Mixed. Are There Alternatives?

How to argue for only 2 residences on highway. They were there when road had no shoulder. Just country road. Now project lane to be 6 lane I live in MN. They added a third lane to the western portion of the interstate that rings the Minneapolis/St. Paul metro area. They added sound barriers everywhere, except my side of the freeway adjacent to my neighborhood. What happened is now that there’s a barrier on the far side of the freeway, the noise bounces off and comes back significantly louder on my side. We can’t even hear our TV during rush hour! Sometimes, when the wind is just right (out of the southwest), we have to close our south-facing bedroom window (in the summer) because it sounds like the traffic is driving right through our bedroom! Even with the windows closed, like they are 9 months out of the year, the freeway noise inside my house is very noticeable. I live for those very rare days when the wind is out of the east or northeast. We do have trees planted on the west side of our house (and no windows at all on that entire side), but again, about 9 months out of the year there are no leaves on them. The reason we were given for there being no abatement in the small se...

The Proxxon MF70 is a nice desktop sized milling machine with a lot of useful add-on

The Proxxon MF70 is a nice desktop sized milling machine with a lot of useful add-on accessories available for it, making it very desirable for a hacker to have one in his or her home workshop. But its 20000 rpm spindle can cause quite the racket and invite red-faced neighbors. Also, how do you use a milling machine in your home-workshop without covering the whole area in metal chips and sawdust? To solve these issues, [Tim Lebacq] is working on Soundproofing his CNC mill conversion. To meet his soundproof goal, he obviously had to first convert the manual MF70 to a CNC version. This is fairly straightforward and has been done on this, and similar machines, in many different ways over the years. [Tim] stuck with using the tried-and-tested controller solution consisting of a Raspberry Pi, an Arduino Uno and a grbl shield sandwich, with stepper motor drivers for the three NEMA17 motors. The electronics are housed inside the reclaimed metal box of an old power supply. Since the Proxxon MF70 is already designed to accept a CNC conversion package, mounting the motors and limit switches is pretty straightforward making it easy for [Tim] to make the upgrade. Soundproofing the box is w...