The weakest point in a laptop case may be the screen hinges, especially in heavily used machines. The mechanical stresses involved with opening a laptop can often break the thin plastic screw bosses and cause the threaded insert to pop out. What do you do? Get a hammer and some tacks of course!
[mightysinetheta]’s solution involves popping the bezel off the offending screen, then aligning the hinges in preparation for drilling holes though the computer’s plastic lid. Then he placed some short tacks though the holes and the hinges. Pressing the hinge down into the lid to ensure a tight fit, the hammer comes out to peen over the tip of the nail. Course that can be time consuming so just bending the tack over and flattening it down with the hammer works just as well.
With the hinge secured back into place his trusty laptop is back in service. The new additions on the back of the lid add a bit of a custom look that is purely functional.
While you’re in there… might want to replace that charging port that’s been wiggling mysteriously.
Sometimes, along comes a hack that is just that. A kludged collection of parts thrown together quickly to solve some problem. [mightysinetheta]’s Upcycled Cat Feeder is just that – no pretensions.
It’s a cat feeder built out of a drill, wall switch and mechanical clock timer for under $10. Pretty much the simplest electric cat feeder you can make. Survives power outages just fine, is single serving, but due to the noise and motion it makes, it is a perfect Pavlovian trainer for the cat. The best way to describe it is as a Rube Goldberg machine.
Set the timer for the planned feed time (up to 12 hours in advance). At the appointed time, the timer triggers, the drill rotates, the old, broken screwdriver chucked in the drill turns. The cord tied to the screwdriver winds up like a winch. This pulls up the lid covering the cat’s dinner plate. The noisy drill announces it’s dinner time. When fully raised, the lid pushes up a short piece of PCV pipe. This flips a switch, that shuts off the drill. If you need build instructions, fear not. [mightysinetheta] has detailed build instructions although the pictures are probably all you’ll need.
Check the video after the break.
Continue reading “Super Simple Cat Feeder”
[Kenneth] built a 5v controlled power outlet inside of a junction box. We’ve seen plenty of projects that can switch 120v outlets using 5v logic for refrigerator controllers, lighting controllers, or grow systems, but they almost always use solid state relays to facilitate the switching. This iteration uses mechanical relays along with the necessary protection circuitry. The project is housed in an extra deep single-gang box and allows for individual switching of the two outlets. You can see this connected to an Arduino switching two lamps after the break.
Continue reading “120v Switching”