Dynamic Subspace

Category: Making

How to Modify 3/8″ Threaded Bolt-On Caster Wheels to Fit Unthreaded 7/16″ Mount Points on Home Hospital Bed

If you have a home hospital bed that needs to be relocated easily but can’t find unthreaded caster wheels, this guide might be helpful to you.

The problem that I recently encountered was a very heavy home hospital bed that needed to be moved around easily without being dragged around on a new floor. The particular bed that I was dealing with was manufactured by Thill, Inc in the USA. It is at least 30 years old and exceedingly heavy.

It sits on four feet capped with glued-in plastic inserts with 7/16″ holes. Judging by late model home hospital beds, there are caster wheels that lock into these holes. Unfortunately, I couldn’t source four of them within the tight time frame that I was needing to make this bed mobile.

I knew that I could get threaded bolt-on casters with non-marking rubber wheels from Rural King in Waycross, Georgia. However, those caster wheels’ bolts were 3/8″ threaded. I needed a way to make those bolts larger and secure on the bed. I thought of how to build a sleeve that would increase the bolt’s diameter but not be easily compressed with use. I had just finished drinking a canned Starbucks Espresso when I imagined how I could use its aluminum can to build a sleeve.

My plan was to cut some of these aluminum cans into sheets that I could wrap around the 3/8″ bolt to increase its size to 7/16″ when it was pushed into the mount point on each foot of the bed. Any aluminum can would work, but I had a the Starbucks cans on-hand, so that’s what I used.

Using a razor, I cut the top and bottom of each can off. Then, I carefully cut down the height of the can to create a sheet of aluminum. Then, I used tin snips to cut the sheets of the needed length and width to match the bolts on the caster wheels.

This is approximately what each sheet looked like, but I used ones with cleaner edges for the final assembly.

I tightly rolled the aluminum sheet around the bolt. Holding it in place with my fingers, I pushed the bolt into the mounting point. If it slid in too easily, I used a longer sheet of aluminum to bulk it up before trying again. The goal was to install the caster wheel securely so that it wouldn’t wobble or fall out if the bed were lifted off the floor.

Once the four caster wheels were installed, the bed could be easily wheeled around on the floor with minimal effort–far easier than trying to lift or drag its heavy mass!

July 7, 2026
LEGO Technics Laptop Stand for 16″ Lenovo Thinkpad P1 Gen4

I’ve been using my Lenovo Thinkpad P1 Gen4 laptop as a desktop replacement system lately, so I wanted to raise its screen higher to avoid slouching and subsequent neck and shoulder pain. While there are lots of solutions to buy, I opted to use the LEGO Technics that I had on hand to build a stand. My goals for the project were facilitating maximum air flow and reliably holding a 4 lb. 5 oz. laptop.

I started by disassembling the folding stand that I had built in 2024, but I noted how I sandwiched a Technic beam between two Technic bricks. The beam’s lower dimension provided a smooth shelf for the laptop’s feet to rest on and the studs on the bricks kept the laptop from sliding off the beam toward the front or rear. I planned to replicate this design in the new laptop stand.

Another important element of the design was an open space beneath the laptop for maximum air flow (this laptop has an NVIDIA RTX A5000 16GB video card that I use for AI workflows). I figured that a rectangular holder for the laptop would work best and allow me to use the black Technic bricks that I had on hand in limited numbers (I have far more light and dark gray elements thanks to all of the Star Wars sets I’ve built over the years).

To strengthen the rectangular frame, there are four layers: top-most brick structure, plates, substructure bricks, and plates. All joints are overlapped, which further strengthens the design.

To support the rectangular laptop frame, I used one L-shaped beam to hold the frame at the bottom and a long Technic brick at 90 degrees to raise the back. As an added support to the back Technic brick, I put a L-shaped beam to apply pressure to the rectangular frame when under the weight of the laptop.

The base of the stand is U-shaped to hold either side’s base in place to prevent any lateral movement, which could cause one of the supports to unhinge.

As a safety measure, I added two Technic L-shaped beams to the bottom center of the laptop frame if not to hold the laptop in place should it slip off then to slow it down as it crashes forward on my desk. I’ve also found this useful for holding paper, such as printed articles, which makes it easy to read and type by looking down-and-up instead of to the left or right.

The stand raises the back of the laptop up 7″, which makes the top of the monitor about even with my eye line. I’ve only been using it a couple of days, but it seems to fit the bill perfectly for my needs.

January 19, 2026
Dorman Products Orange Metal Parts Drawers

Ellis Auto Parts, my family’s business that closed down in 1996 when my parents retired, used to carry Dorman Products, a line of automotive hardware such as bolts, nuts, washers, pins, caps, and a variety of other kinds of parts. While my dad sold a lot of our remaining stock when he closed the store, he kept a lot of unsold product and the metal drawers that we kept the stock in. When I was at home, I stacked up more of these drawers to create a grid against one wall. The full grid is 5 x 5, but I took a photo of 4 x 4 because one of the corner bins was missing a drawer that I couldn’t find–it is likely somewhere in the shop but waits to be rediscovered. I’m glad that we had access to all of these parts during my trip this time, because we made use of them in our many projects.

July 11, 2025
How to Update Your Linux Kernel on Debian Bookworm 12 to the Latest Available on Backports
$terminal screen with system info: jason@desktop:~$ screenfetch | lolcat _,met$$$$$gg. jason@desktop ,g$$$$$$$$$$$$$$$P. OS: Debian 12 bookworm ,g$$P"" """Y$$.". Kernel: x86_64 Linux 6.12.32+bpo-amd64 ,$$P' `$$$. Uptime: 10h 8m ',$$P ,ggs. `$$b: Packages: 2323 `d$$' ,$P"' . $$$ Shell: bash 5.2.15 $$P d$' , $$P Resolution: 1920x1080 $$: $$. - ,d$$' DE: Xfce $$\; Y$b._ _,d$P' WM: Xfwm4 Y$$. `.`"Y$$$$P"' WM Theme: Haiku-Alpha `$$b "-.__ GTK Theme: BeOS-r5-GTK-master [GTK2] `Y$$ Icon Theme: BeOS-r5-Icons-master `Y$$. Font: Swis721 BT 9 `$$b. Disk: 7.7T / 11T (75%) `Y$$b. CPU: AMD Ryzen 7 7700 8-Core @ 16x 5.389GHz `"Y$b._ GPU: NVIDIA GeForce RTX 3090, NVIDIA RTX A4000, NVIDIA RTX A4000, NVIDIA RTX A4000 `"""" RAM: 9486MiB / 63916MiB$

If you’re like me, you might have newer computer hardware that isn’t fully supported by Linux kernel 6.1, which is installed with Debian Bookworm 12. Thankfully, Debian offers Backports, or newer software in testing in Trixie, the development name for Debian 13, that will eventually find its way into future Debian releases for use on an otherwise stable release of Bookworm.

Updating to a newer kernel often brings more hardware compatibility. However, it’s important to remember that using a backport kernel can introduce potential compatibility issues with the software officially supported on Bookworm. Even if installing the latest kernel causes some issues, you can choose to boot from one of your older 6.1 kernels on your install as long as you don’t delete them (by using the apt autoremove command).

I wrote this guide based on my experience installing Linux kernel 6.12 from Backports with the non-free firmware that my hardware needs to work. If you are trying to keep your system free from non-free software, you can omit those references in the instructions below.

Before doing any changes to your Debian installation, remember to backup your files first. Saving important files in more than one media and storing it backups in different physical locations is best practice.

After backing up your files, make sure your install is up-to-date with these commands:
```
sudo apt update
sudo apt upgrade
```
After those updates complete, it’s a good rule of thumb to do a reboot to begin working with a clean slate.

Next, add Debian Backports to /etc/apt sources.list. I used vi to do this:
```
sudo vi /etc/apt/sources.list
```
In vi, arrow down to the bottom line, type a lowercase “o” to add a blank line below the current line, type lowercase “i” to enter input mode, and type the following line into the document:
```
deb http://deb.debian.org/debian bookworm-backports main contrib non-free non-free-firmware
```
After double checking the added line, press the “Esc” key, and type “:wq” to write the file and quit vi.

Now, you need to update apt again:
```
sudo apt update
```
After the completes, enter this command to install the latest kernel from backports along with the kernel’s headers and firmware that might be needed for your hardware (such as networking card, video card drivers, etc.).
```
sudo apt install -t bookworm-backports linux-image-amd64 linux-headers-amd64 firmware-misc-nonfree
```
It might take awhile for the installation to complete. If there are no errors, it should return you to your terminal prompt. If it did, reboot your computer to load the new kernel.

After your computer boots up again, you can verify that you are running the latest kernel by entering this command:
```
uname -r
```
After installing the latest kernel, my computer reports this from the uname -r command:
```
6.12.32+bpo-amd64
```
July 8, 2025
A Simple Moveable Platform for an Oscillating Spindle Sander

Another project for my dad and I was setting up his Grizzly oscillating spindle sander, which had been sitting on a broken pallet for some time.

He had a rolling Shop Fox equipment stand, but it was slightly too large for the sander’s base. So, we cut a piece of 3/4″ plywood to fill its support area and distribute the weight of the sander.

Then, we layered some boards to create a ramp from the pallet the sander was on down to the Shop Fox equipment mover.

When he’s ready to use the sander, the Shop Fox mover has floating feet that can be lowered to take the weight off the front caster wheels.

July 4, 2025