# Day 87-91: Milling to the Max

Monday, Jan 28-Friday, Feb 1

I am finally starting to get my sea legs back and adjust to working so much. Figuring some stuff out. Starting to get materials put away, starting to get my office tidied up, got grades updated in all my classes, just generally finally starting to feel like I’m doing more than drowning. It’s a nice feeling. I was not feeling well Wednesday evening and all day Thursday, which put me right back behind again. It was nice to finally have a chance to rest, though. Friday was a catching-up scramble, but with five more hours in the trailer after school, I got all the milling done that needed doing before the weekend, or at least that I knew about before the weekend.

Physics: Waves and sounds! Wooooohoooooo! Like, for real, my favorite topic. Love playing with waves and springs. Two days after each exam we do the exam review, and I use that time to let students do corrections and ask questions, and we had some really great conversations about thermodynamics.

The next sound day was Doppler effect, which is super fun. We did an online thing, I whirled a singing ball around my head to show how they hear the frequency change, and generally got to do fun things. Then, at long last, we got to talk about resonance and forced vibration. That’s basically what my degree was in at HMC (analyzing structures for resonance), so I always get excited about it. I played music for them, showed them the difference between a music box with and without a soundboard and the way that any hard, flat surface can work as one. The blinks and wonder on faces for this demo are my favorite. We also watched the Tacoma Narrows Bridge video and collectively mourned Tubby the Dog, the only casualty of the disaster. Poor lil guy.

Honors Physics: Finishing up optics. Did more math on thin film interference, anatomy of the eye, how color perception works, and other cool things. We watched a few videos about optical illusions, and they super duper loved it. They thought the way using three cones to discern color was fascinating, along with how their brains are jerks and can make things look like they are moving when they actually aren’t. Damn tricky brains. For assessment, I am bringing back last year’s “write your own exam question” method of writing the exam at last. These kids have been asking if we were going to do that since August, and I kept telling them not until after winter break. Well! Here we are! Review and question writing will happen this week, then midterm next week.

Then!

Next topic: Modern Physics! We have 1.5 weeks to talk about quantum physics, special relativity, mass-energy equivalence, atomic physics, all that super exciting stuff. Yay!

AP Physics: Finishing up electrostatics and beginning circuits. I love this unit so much because the students get to DO things and MEASURE things and it’s so much more hands on than electrostatics. We finished up capacitance on Tuesday, so Wednesday was our first time making lightbulbs light up, which is always an exciting day. Some of my students have more experience than others with electronics (the theater tech and radio kids know quite a bit), but everyone got materials to play with and try different things with, and if some were more advanced ideas than others, that’s intentional. Gonna make so many circuits! Wednesday was a whole lot of building and learning more about the multimeter, and Friday was the midterm.

Robotics: All the wheels are on thanks to this past weekend of work, and we got the motors, controllers, and electronics all hooked up and ready to go. The problem is we can’t get the CAN value on the motor controllers to be anything but 0. They won’t hold unique identifiers. So, we can get them to do anything at all we want them to do, but they all do the exact same thing. That means our robot can spin to the right or spin to the left, but cannot go forward or backwards as of Monday night. Next step was reaching out for help, and we got some answers over Monday night. Tuesday was more testing after answers came back, and we got the robot going! The motors make the wheels go! Yaaaay!

I also got to unpack a handful of packages. I have loaded up my credit card with literally thousands and thousands of dollars for this robotics team (which gets reimbursed, eventually), but it means I am constantly getting presents in the mail. I love opening packages and getting new things, especially when it’s USEFUL and NECESSARY things that make the robotics program better and better. I also sat for about two hours staring at CAD and drawing out parts and doing math to figure out how I needed to get the mill set up to shape some pieces that we need. A student double checked all the things, so we were feeling reasonably confident about being all set to go.

Wednesday and Thursday were a wash. Friday was every spare moment in the trailer getting things sorted out for the weekend, but I got all the pieces made that needed making and literally only I could make on the CNC mill (her name is Millificent). Now that I have the basic foundation of milling sorted, the vast majority of the time spent is doing math and then test-and-iterate-ing until the output matches the requirements. We’ve got some work ahead of us to solve some problems surrounding drilling, tapping, mounting, and positioning a rack-and-pinion system, and I have a handful more taps on the way so that when we break them (they break so, so easily they’re effectively consumables) we’ll be able to keep working.

I also taught some of the robotics students about the physics of turning the canned air upside down to make things super cold and then giggling about it a lot. The giggling is a Very Important part of the Science.