Threads and Nuts

I bought a quarter inch aluminum plate and mounted it to the blade unit using some muffler clamps (they were exactly the right size). This should let me mount the blade unit at an angle. I was able to re-use these hook shaped bolts. The distance from maximum to minimum height looks good with maybe 3″ – 4″ maximum height, which is about what the old mower had. All I needed was some nuts to fasten the bolts to the plate. Had some that were the right size, but the threads were wrong. They weren’t metric so not sure what the issue was. I see there are different thread sizes and this was obviously more threads per inch than my standard bolts. I ordered some on Amazon, but somehow ordered 5/8″, which is way too big. I would say I meant 5/16″ but it really seems to be 1/4″ (4/16″). Will have to wait for another Amazon cycle. Will probably order some conduit to secure and protect the wires and then that should be it for version 1.0

Raspberry Pi Zero Slideshow

Gave my Mom one of those Electronic LCD Picture Frames, that I loaded up with some family photos. She liked it and even my sisters enjoyed looking at the old photos. I used a flash card with a few hundred photos but the frame itself is small and the LCD screen isn’t very good. I wondered about making something simple that plugs into the TV that Mom (or anyone) could use. I wanted it as simple as possible, ideally just a power plug and an HDMI output.

I put together a little Raspberry Pi Zero gadget that does a pretty good job. I’m using the Linux utility feh, which does exactly what I want it to do. From the command line you can randomly display all the photos in a directory tree in full screen mode. The command I use is:

/usr/bin/feh --slideshow-delay 7.0 --auto-zoom --borderless --fullscreen --recursive --randomize --auto-rotate --hide-pointer /usr/pi/Pictures/

The photos are all in the /usr/pi/Pictures directory and the delay between pictures is seven seconds. I put this into a file called in the pi user home directory (/home/pi). This is the default user for Raspberry Pi OS. To get this script to execute on start-up a file called /etc/xdg/autostart/display.desktop is created with the following content:

[Desktop Entry]

This file will run the slideshow script when the Raspberry Pi boots up. One last bit. You don’t want anything to interfere with the slideshow, so you should turn off the screensaver. This is done in the raspi-config configuration tool under the Preferences menu. Select the Screen Blanking option and disable it. Lastly, you don’t want an upgrade request to interrupt things either, so we can turn that off, too. The following commands should disable requests for updates.

sudo systemctl mask apt-daily-upgrade
sudo systemctl mask apt-daily
sudo systemctl disable apt-daily-upgrade.timer
sudo systemctl disable apt-daily.timer

Looks like it works. Bought a 256GB flash card and will load it up with a few thousand old photos I have in the archive. Will be visiting Mom in a few weeks. Hope she likes it.

American Deaths Squads

People attacked by right wing maniacs in America sure have bad luck with their other health problems. This week we learned that George Floyd died of heart disesase, coincidentally, while police officers were kneeling on his neck and back for almost ten minutes. And. And. The police officer defending the US Capitol during the Jan 6 riot dies several hours after the riot of “natural causes”. Two other officers committed suicide just days after the riots. Unrelated, I am sure. Would like to hear more about those two.

Police officer died of ‘natural’ causes day after Capitol riot: Medical examiner

Defense expert testifies George Floyd died of heart disease, car exhaust fumes

One Last Piece

The electric riding mower is almost ready for its first test. I am happy with the drive train and have even added a switch to the brake that that turns off the motor when braking. I was going to turn off the motor manually when braking, but too easy to burn up another fuse that way, or worse.

Still playing around with how to attach the lift mechanism to the blades. My biggest concern right now is what happens when you bump into something. The old gas mower was heavy duty, and I still managed to bend and break stuff. This won’t be as strong and will break more easily. I just don’t have a good feel for how much movement to allow. The old deck was mounted at four points which was more stable. This will be just two points. Maybe I should have kept more of the old lift mechanism, but it was a bit complicated. Right now I’m thinking of ways to limit movement. Things will break if you hit them hard enough, but I’m going to try to keep it to a minimum. Actually I suppose I will be easier on this machine than I was on the old gas mower.

One other bit. Sometimes my progress depends on Amazon deliveries. There are two parts to the old lift mechanism. I want to reuse them and each has an advantage and disadvantage. I’m also learned that although they seem interchangeable, one is maybe a quarter of an inch offset. Nothing some big washers wouldn’t fix. Except I didn’t have any big washers. So two days to mull it over while Amazon ships my washers.

Texas Energy Blame Game

The state government in Texas is trying to blame renewables for their failures in the Big Freeze. I won’t even say it was gas that was the problem. Just failure to winterize the system, which was heavily gas based. Not widely discussed, but lack of gas from Texas also left millions in Mexico without power. Hard to blame that on renewables.

A good read on the subject that quotes a former ERCOT member:

“They would have to be complete idiots if they think what they’re doing is solving the problem,” he said. He doesn’t actually think elected officials are idiots, he added, but he does think they are acting out of political convenience.

Texas Politicians Aim to Penalize Wind and Solar in Response to Outages. Are Renewables Now Strong Enough to Defend Themselves?