![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
arisoturaThis is something I've talked about before, and we just got around to fixing it.
The buttons on the front of the radio are as follows: MIXER | SPRACHE | KONZERT | SOLO | JAZZ - it isn't completely obvious because the printings have faded.
They're audio equalizer settings, basically. MIXER enables the separate bass/treble controls, the other ones are presets for common types of radio broadcasts (in 1958, that is).
In our case, the MIXER button was missing. It was problematic because the buttons are spring-loaded, that's how they pop back out when you press another one, but for the MIXER button, both the button and the spring were lost, so it was stuck in the pressed position.
This is the button module, you can see how it's made. For each button, there's a strip of PCB-like material that holds contacts. The strip itself pokes through the front of the assembly, and the end of it holds the spring and the button face.
I tried to remove one of the other buttons so we could measure it and model it, but in the process I accidentally broke its stem. Shows how flimsy those things are... It will get the same repair as the missing MIXER button.
The basic idea for this repair was to make a splint to replace the broken part of the stem, mount an adequate new spring, and make a new button. I decided to keep the pieces separate so we could adjust them together as needed.
The annoying part is that, as far as the MIXER button is concerned, the stem broke off in such a way that when it's in its pressed position, it sits flush with the front plate of the switch module. I couldn't just glue the splint to the edge of the stem, because there isn't nearly enough contact surface to get a strong bond. So this needed more work.
I first disassembled the button module.
You can also see the splint pieces we 3D-printed. The Y shape is designed to grab the original piece from both sides, ensuring a strong bond.
Since the splints are thicker than the original stems, I had to enlarge the openings in the front plate.
Then the splints are glued to the original pieces. Note that the splints are designed so that the thicker section is always intersecting the front plate.
I reassembled the button module with the newly fixed pieces. The splints turned out to be a bit short, but nothing bad.
I added the springs and the second button back. For the first button (the lost MIXER button), I was able to find a spring with the correct diameter and length. It's a bit stiffer than the original springs, but it will do the job. I also dremel'd a random piece of metal to make the small piece that holds the spring on the stem.
I cleaned up the assembly and made sure everything was operating smoothly.
This is the end result. We 3D-printed a new button.
Yes, it's not the correct color. This would horrify purists, for sure.
But well, we do with what we got. A more proper way to make this new button would be to use resin, either cast in a mold or in a resin 3D-printer. That would replicate the original button's appearance. One could even try different dyes to replicate the original color. Then we'd have to figure out how to print a label onto the button, too...
I don't exclude trying to do things more properly, but for now we don't have that kind of means... and hey, this is functional.
While I was at it, I was also able to fix the problem with the AM/FM tuner switch, so now that operates smoothly. The last problem is the magic eye tube not being properly mounted, and a friend is trying to figure out a solution for this.
The buttons on the front of the radio are as follows: MIXER | SPRACHE | KONZERT | SOLO | JAZZ - it isn't completely obvious because the printings have faded.
They're audio equalizer settings, basically. MIXER enables the separate bass/treble controls, the other ones are presets for common types of radio broadcasts (in 1958, that is).
In our case, the MIXER button was missing. It was problematic because the buttons are spring-loaded, that's how they pop back out when you press another one, but for the MIXER button, both the button and the spring were lost, so it was stuck in the pressed position.
This is the button module, you can see how it's made. For each button, there's a strip of PCB-like material that holds contacts. The strip itself pokes through the front of the assembly, and the end of it holds the spring and the button face.
I tried to remove one of the other buttons so we could measure it and model it, but in the process I accidentally broke its stem. Shows how flimsy those things are... It will get the same repair as the missing MIXER button.
The basic idea for this repair was to make a splint to replace the broken part of the stem, mount an adequate new spring, and make a new button. I decided to keep the pieces separate so we could adjust them together as needed.
The annoying part is that, as far as the MIXER button is concerned, the stem broke off in such a way that when it's in its pressed position, it sits flush with the front plate of the switch module. I couldn't just glue the splint to the edge of the stem, because there isn't nearly enough contact surface to get a strong bond. So this needed more work.
I first disassembled the button module.
You can also see the splint pieces we 3D-printed. The Y shape is designed to grab the original piece from both sides, ensuring a strong bond.
Since the splints are thicker than the original stems, I had to enlarge the openings in the front plate.
Then the splints are glued to the original pieces. Note that the splints are designed so that the thicker section is always intersecting the front plate.
I reassembled the button module with the newly fixed pieces. The splints turned out to be a bit short, but nothing bad.
I added the springs and the second button back. For the first button (the lost MIXER button), I was able to find a spring with the correct diameter and length. It's a bit stiffer than the original springs, but it will do the job. I also dremel'd a random piece of metal to make the small piece that holds the spring on the stem.
I cleaned up the assembly and made sure everything was operating smoothly.
This is the end result. We 3D-printed a new button.
Yes, it's not the correct color. This would horrify purists, for sure.
But well, we do with what we got. A more proper way to make this new button would be to use resin, either cast in a mold or in a resin 3D-printer. That would replicate the original button's appearance. One could even try different dyes to replicate the original color. Then we'd have to figure out how to print a label onto the button, too...
I don't exclude trying to do things more properly, but for now we don't have that kind of means... and hey, this is functional.
While I was at it, I was also able to fix the problem with the AM/FM tuner switch, so now that operates smoothly. The last problem is the magic eye tube not being properly mounted, and a friend is trying to figure out a solution for this.
