I got an old Anet A8 printer from my makerspace revived and connected to Astroprint for remote monitoring. Had a mishap with the Z axis limit switch not working, so when it homed it plunged into the build plate and left a dent. Thankfully no damage to the extruding module though.
I won the #osf Hackathon live event today! Shoutout to @winston and the others for putting it all together! Here was my submission for the challenge to build a “spam bot”. It’s an Arduino Leonardo which is recognized as a keyboard and types the word “Spam” a few times a second until unplugged. Now comes the challenge of removing the program without it writing “Spam” in the IDE a million times while it waits to upload new code.
I continued working on my tennis ball launcher. I got both flywheel pieces printed and assembled, but could only find enough quarters to fill half the slots. So far it weighs 650g, but should be able to get past 1kg with all quarters. The hope is these quarters will add enough weight far enough from the axis of rotation to keep momentum as tennis balls shoot, giving more repeatable and rapid shots.
I continued manufacturing face shields for special ed teachers today. I spent a while testing and adjusting the speeds and feeds until I was satisfied, then cut out a bunch of the shields. The only bit I have is an upcut end mill, so I need to use a paint stick and vacuum to hold the material down as it cuts.
I made myself a time blocking sheet to try to have more structure to the day. I’m using the Pomodoro technique to maintain focus, as well as blocking off sections of the day for various tasks. Since classes are looking to be online for the foreseeable future, I’m hoping this will help me maintain focus with so many distractions when studying at home.
Began testing a pair of LoRa radios for a DIY RC plane remote controller. Spent like 3 hours troubleshooting code before I discovered I was using the library for a different style radio. I’m now able to instantiate a new radio object and configure it. Tomorrow, hopefully I can get them communicating and test the range.
Worked on some wings for my RC plane today. Top wing is what came with the plane, bottom is what I lasercut and assembled. It’s slightly larger, and has control surfaces on the wing for flaps/ailerons.
I 3D printed wheel tread for an RC plane landing gear out of PCTPE today. It’s supposed to be similar strength to nylon, but more flexible. Also just as difficult to print with. I tried a new slicing setting: concentric infill, to maintain the radial symmetry. It’s not necessary for this, but later I’m thinking about printing a flywheel which will be spinning over 1000 rpm, so thought this would be a good test to see if it’s viable.
Modded a broken RC plane with new electronics and an overpowered motor. I didn’t give the rudder enough range of motion, so I was barely able to turn before it crashed into a tree and got stuck. For what it’s worth, I didn’t have time to install landing gear, so in a tree was probably a better landing than bellyflopping and hoping the prop wouldn’t snap.
Began a course on simulations in Fusion 360.
I got to try some milling today! Need to cut 0.060" polycarb for face shields. First attempt was on an industrial CNC mill which I though was a bit overkill. Then I tried on a Shapeoko, but discovered the work area is deceivingly small compared to the overall size. I needed to cancel after it hit the edge and got misaligned.
I did some fun math today on finding velocity of a shooting object. I’m trying to design a tennis ball shooter which uses a single wheel and spins it along an arc to get up to speed, before launching at a certain angle. Originally I assumed the velocity of the ball would be half that of the angular velocity of the flywheel, but quickly realized it’s more complicated than that. I did some research, and found what I’m doing to be similar to equations modeling reductions on a planetary gear systems. I got a few equations for determining planetary gear reduction, and solved for the relative angular velocity of the ball and speed of the ball based on the diameter of the flywheel and tennis ball. Then I added the speed of the motor and solved for the speed of the ball. TLDR; A 1200 rmp motor with 6" diameter drum can launch a 3" diameter ball around 10 mph.
I just found out about this feature and thought I’d start a streak! I’ve been working on 3D printing clear face masks for special ed teachers in my district. I print them at my communities makerspace but found it tedious to wait around to print, so installing Octoprint on a Raspberry Pi for remote monitoring. Right now working through installing the image on an SD card.