Over the last few years I've posted here on the forum several times extolling the virtues of 3D printing...here is my latest example. The Nordmende Kadett C I'm working on (viewtopic.php?f=6&t=411340) has a plastic cabinet, and the feet are molded into it. One was broken.So I ground the remaining pieces away and smoothed it out.Then I used the good foot to design a replacement and, after also designing and printing a matching gluing jig, I used some JB Weld quick setting epoxy to glue it into place.The results are very nice...the pictures make it look more obvious than it looks with the naked eye...a person would have to give it more than a quick glance to notice that it's a repair.

I also printed some new chassis mounting grommets using flexible filament.I've printed quite a few new grommets, primarily for tuning cap mounts. They aren't as soft as actual rubber grommets, but usually far softer than the originals after 70-80-90 years in place.

I highly recommend 3D printing...almost every radio I've restored has benefited in some way from the printer (actually I have 2 now)...some with just a speaker guard or gluing jig or something like that, but most have parts in them that I have designed and printed.

Rich

3D printing is pretty easy. Using a CAD program is something else.

Vince

Your point is valid Vince. But nobody should let that scare them off. I picked this up entirely on my own...there are many tutorials available online . I started out using FreeCAD. It was a little clunky at that time...my guess is that it's improved since then. When I got my first 3d printer I started using the free version of Fusion 360. It's very powerful and in general quite easy to learn and use...tons of tutorials out there. I've been using Fusion 360 for 5 years now and feel quite comfortable using it. When I first started I think it only took a month or two to actually feel like I sort of knew what I was doing.

Rich

Good information. Thanks for sharing your experience.

Vince

I have used openscad as well as Sketchup. If you enjoyed geometry, and have reasonable math skills, openscad can be fun. Because it is based on instructions rather than a drawing interface, the openscad designs can be resized and reused quickly. Sketchup is over the top for many simple projects. These lampholders were done in openscad, as well as the mold used to make the silicon one. viewtopic.php?f=13&t=411546

Thanks for the input iptvengineer! I meant to include in my previous post that there are several good, free options for designing 3d models. I've never used either openscad or Sketchup, but have seen them referenced often and know that a lot of people use them.

Rich

Openscad is quite easy, a simple 'cookie cutter' based on a few parameters. Easy to adapt/change.

$fn=300;

DIAMETER=42;
HEIGHT=10;
CONE_HT=3;
OVERHANG=4;
WALL=1.2;
NOZZLE=0.4;

//Base
difference()
{
cylinder(WALL,d=DIAMETER+(2*OVERHANG), center = true);
cylinder(WALL,d=DIAMETER, center = true);
}

// Shell
translate([0,0,HEIGHT/2])
difference()
{
cylinder(HEIGHT,d=DIAMETER+(2*WALL), center = true);
cylinder(HEIGHT,d=DIAMETER, center = true);
}

// Cutting Tip
translate([0,0,HEIGHT+CONE_HT/2])
difference()
{
cylinder(CONE_HT,(DIAMETER/2+WALL), (DIAMETER)/2+NOZZLE, center = true);
cylinder(CONE_HT,d=DIAMETER, center = true);
}

Rich, thanks again for printing the Packard Bell tuning knobs and trim and then graciously sending me a bag of them.
I have since sent knobs to two other PB owners, so your generosity lead to 3 saved radios.

I would be interested to know the material involved (ink) used in a 3D printer. How rugged is it? I imagine abrittle fragile end product. I could be wrong. But I certainly don't magine an end product that is anything other than mere facsimile of the original part, perhaps beautiful but certainly weak or breakable.

There are many styles of filament for 3D printers, which you can use depends on your printer. ABS plastic, PLA, PETG are all pretty common.

Peter

The original knobs and trim on the Packard Bell radios were Tenite. It isn't hard to beat that stuff with a modern plastic that doesn't shrink and is tough like polypropylene rope. 3D parts are better.

The escutcheons were Tenite (or some similar warping plastic) but P.B thankfully used Bakelite knobs, and pushbuttons in all the sets I've run across. Ironically Stromberg Carlson used Tenite for both in the pre war years, and they were supposed to be more of a premium brand.
Regards
Arran

Wet sanding gets the parts smooth. I am very close on the Emerspn parts, we just need to get the color right.

That's not really the case at all. As mentioned there are many styles of filament for 3D printers. When I was working there were third party dealers making some OEM plastic replacement parts on a 3D printer that were as strong as the originals.

Yes, it is strong. They even 3D print metal jet engine parts.

Yes, Bakelite knobs and pushbuttons on the front, but the tuning knob that is on the side of some models has a long stem and it is Tenite or similar. The stem shrinks onto the shaft and pulling on the large knob destroys it.
A new knob is really the only option for those models.

When Rich printed the new knobs he had to find the size of hole that would grip the shaft just right. The originals are way too tight from shrinkage.
The other issue was finding plastic thread in the right shade of brown.
The picture above shows the new parts installed on his Packard Bell.

He sent me a bag of parts he made in slightly different colors and I chose what I wanted and gave the remaining two knobs away.

I got this 5N cheap I think because the owner couldn't budge the knob to service the chassis.
To pull the broken stub, I built a little slide hammer and it took 4 or 5 hard whacks to crack it loose.

Below that, a pic of a Tenite escutcheon with 3D printed replacements before sanding.