Category Archives: Uncategorized
I spent a long time this weekend troubleshooting a Commodore VIC1541 disk drive only to have it spontaneously start working. I cleaned the belt, de-oxidized the connectors, re-flowed some suspicious looking solder joints, and tried a variety of different disks. Its working reliably now though and I’m able to use it as a bridge between the internet and the C64 via a ZoomFloppy. The ZoomFloppy connects the 1541 to a PC via USB so that disk images can be written and then later loaded on the C64.
The home office has some bifold doors connecting it to the foyer. Normally I’d like to leave these doors open since it allows light & visibility to the front door, but that would also allow cats to enter the office (usually at the worst times). The solution seemed to be changing to bifold doors with glass panels, however these are very expensive. Since the existing doors were already good quality solid wood though, a good compromise seemed to be modifying them to add glass. I was able to find tempered glass for a reasonable cost online, so I went ahead with this project. Tempered glass is the key since it will break into small (less dangerous) pieces, it’s a code requirement for doors in most locations. The process went as follows:
- Cut a middle section out of the panels on each door. This allowed room for the next step.
- Pull the remnants of the panel edges out of the groove in each door frame.
- Route one side of the door frame flush with the bottom of the groove.
- Install glass panel.
- Make trim piece to hold glass in place, this piece basically replaces the piece of the original groove edge that was routed away.
- Carefully tack trim in place.
- Fill/Sand/prime/paint trim pieces.
Following-up on the Apple IIc computer refresh, I recently cleaned up the IIc’s monitor. Disassembly of CRTs can be dangerous due to high voltages, but at the point of disassembly it had been unplugged for a few weeks and I made sure to discharge the tube and capacitors as soon as I could. From there it was just a matter of cleaning the plastics, using a magic eraser for scuffs, and de-yellowing. The de-yellowing is accomplished by covering the surfaces in peroxide, putting the parts in bags, and then submerging those bags in a bath of hot water kept warm by a sous vide heater.
A few of the potentiometers for size/position/brightness were dirty, causing the picture to cut out unless adjusted perfectly. This was resolved by spraying some contact cleaner under the knobs and exercising them.
The clutch on my car finally started slipping when under full power. This wasn’t completely unexpected since it originally came from a high-traffic area of NJ. I was able to get it replaced over the past two weekends plus a couple of weeknights. There wasn’t anything particularly difficult about this and it’s well documented online, just lots of small challenges in a row with figuring out how to access various fasteners.
While I was at it I took the opportunity to replace belts, plugs, change the supercharger oil, etc.
Last weekend I got around to populating and testing the piano valve control board. Unfortunately it did not work when initially powered on, I was able to track this down with a scope to problems with the level shift circuit between the pi and the shift registers. Rather than troubleshoot this farther I ended up re-designing and re-etching the board to replace my transistor array level shifter with an off-the-shelf level shifter sub-board. I also took this opportunity to #1 redesign the solenoid wire connections so that a pin header connection could be used rather than having the wires directly soldered to the board and #2 add a connector to the edge of the board to use the pi’s pin header connection.
In the mean time I had also created a 3d printed enclosure to hold the board on the back of the valve bank. This was important as it allowed the final solenoid wire lengths to be determined and I soldered all the solenoid wires onto a pin header. I also 3d printed a support ring to stabilize the pin header and hot glued it all together to act as a single strain relieved connector.
This weekend I was able to finish and test the re-design. All channels seem to be working OK and I’m able to control the piano keys individually from a tablet using a python script. I have some python scripts working that successfully decode the MIDI files, but I haven’t connected the dots between this and the hardware yet, that’ll be the next step along with hopefully adding a web interface.
The utility trailer frequently gets used off-road around the yard and woods for moving downed trees/branches, compost, rock, tools, etc. As a result, the standard plastic lights have taken a beating and I’ve had to replace them at least once. Since one of the lights was broken again recently I decided to upgrade them to use a standard all-metal semi trailer style light enclosure. This style of light fits better vertically than horizontally on this trailer, so I modified the enclosure to move the circular side light from the end of the light to the side. I then welded the light enclosure onto the trailer; the size of the light worked out perfectly to connect it to the old light mount and also the top rail of the trailer on each side, making it very strong. At the same time I replaced the side running lights with a low profile LED version and added a guard/deflector made from a small section of scrap rebar.
I cut the trap door in the desktop, secured it back with some neat invisible hinges, and got it all assembled.
Continuing with the desk project, this weekend I built the desktop. I first planed down a few more pieces of the oak tree I cut down and dried last winter. This was supplemented with a few pieces of oak from a local hardwood store. I ran every piece through the table saw to get the edges straight, and then I laid the pieces together and perfected the joints with a hand plane. Once all the joints aligned perfectly I glued and clamped the pieces together with pipe clamps. Once the glue dried I cut the ends to length and added ends, making sure that the two outer attachments were slotted to allow for expansion/contraction.
There was some unavoidable variation in the joints across the top surface from the glue-up and this was leveled out with a hand power planer. The planer marks were then leveled with a belt sander and the belt sander scratches were removed with a orbital sander. I finished it off with stain and then applied polyurethane with a roller while using a torch to pop bubbles. The planing steps created a ton of dust so I didn’t get any in-progress pictures, here’s the result:
Next I’ll cut the trap door for the monitors and give it a final sanding and 2nd coat of polyurethane before attaching it to the desk.