DIY Sisal Bristle Oil Brush

I recently have been doing a lot of drilling through metal which requires cutting oil to keep the bit sharp . I’m using used air compressor oil (stored in a plastic water bottle) and I needed a brush to apply it. The silverfish ate the bristles of all the old brushes I had stored in the shed, so I decided to make my own. I made a brush out of sisal twine, aluminum tubing, and an old screwdriver. It's hacked together but it works quite well. The section of sisal twine is held in place inside the tube by a screw. When the bristles wear out, it is easy to replace with a new piece of twine.

Buzzer with Antique Capacitor

This circuit uses a momentary push button, a buzzer, and a capacitor. I got this antique capacitor from an estate sale. It is over twice the size of a modern one of the same capacity and voltage. (400 μF at 25 Volts). A similar size modern capacitor has about 12 times the capacity at the same voltage.
This is one of my projects that has been shown at the Austin and Floresville Maker Faires. I plan to show it at the San Antonio Maker Faire soon. This is a favorite among kids, who like to push the button repetitively.  The capacitor stores power and slowly releases it. This gives the buzzer an interesting sound. Dad describes as annoying and Mom says it sounds like a cartoon spring "boing".

Overcomplicated Alarm Clock

Bored by the standard clock radio, I wanted something with bed-shaking bass to wake up to. I decided to modify my sound system to add a secondary power input controlled by a mechanical timer. The timer is the type you plug your lamp into when you go on vacation so people think you are home, although that didn't work in the Home Alone movie. I set the timer to turn the power on for about an hour around the time the alarm app on my tablet is set to. The app on my tablet is set to use loud music as the alarm. My favorite is a song called Gopnik by DJ Blyatman.  https://www.youtube.com/watch?v=2tch4J_pP9o I don't understand the words, but I like the style.
To prevent the two power supplies from interfering with each other, I added a common anode dual diode (STPS3045CW). Here is a datasheet from the manufacturer. I salvaged the diode from a switch mode power supply.
The green LED indicates power from the bench power supply. If it is on it will be the dominant power source. The orange light indicates the alarm power source. If both power supplies are on, the bench power supply will do the work.
The blue part is the amplifier. I use it all the time when I am listening to music. My tablet by itself has tiny speakers and therefore no bass whatsoever. I bought the amplifier through amazon. http://amzn.to/2HCxCOw

Instructions for Light Sensor Learning Kit

I signed up for the Amazon Affiliate program. This gives me a small percentage if someone buys a product through my affiliate link. It doesn't cost the buyer any extra, and I can post a link to any product they sell (except gift cards). This inspired me to put together some easy electronics projects with a list of links so you can build them yourself. 

Last year at the Austin and Floresville Maker Faires, I showed off my "Electronic Pinscreen" project. Here are instructions for how to build your own on a much smaller scale.

To build a smaller version of my LED matrix, you will need 4 LEDs, 4 light sensors, and a battery pack with batteries. While you can buy smaller packages of parts, it's a much better deal to buy them in bulk. For 12 kits, the total price would be around $30.
Now that I'm old enough, I solder all my projects. Maker Faires are a good place to learn how. I went to a class at the Austin Maker Faire a long time ago, and the Kansas City Maker Faire in 2017. But if you don't know how to solder, you can do this project with breadboards instead. Or have the kids twist the wires together and test it, and then have the parents solder it. Lead-free solder would make it safer for kids to handle the finished product. I don't like lead-free solder because it's harder to work with. (Safety note from Mom- soldering should be done in a well-ventilated area on a non-flammable surface that isn't your fancy dining table, with experienced adult supervision because it's over 600 degrees F, and make sure to wash hands afterwards.)

Take two 4" pieces of bare wire, lay them out parallel, about 2 inches apart. Connect all the negative (short legs) of the LEDs to one bare wire. Connect one side of each photocell to the other bare wire. Connect the positive (long leg) of each LED to the other side of each photocell. Connect the red (positive) wire from the battery holder to the bare wire with photocells. Connect the black (negative) wire from the battery holder to the bare wire with the LEDs. It should match the schematic.
Test, and then solder.
You can mount the finished project on cardboard to keep it secure.

Parts list for 12 kits:
uncoated or stripped wire, 8 inches per kit
50 white LEDs http://amzn.to/2Dnzp7G
(20+30) Photoresistors http://amzn.to/2GlVtD1 and http://amzn.to/2GkeqG1
12 Battery Holders (hold 2 AAs each)  http://amzn.to/2p4AUDr

Optional- 2 six-packs of mini breadboards http://amzn.to/2FM5k7e
24 AA Batteries- http://amzn.to/2Hrdn6q