3D Printed Pactec Box Panel

As part of the Thermal Lockout project, I planned to put a pair of big pushbutton switches on the end of a little Pactec box, thusly:

I was in the midst of figuring out how to clamp that tiny panel to the Sherline milling machine’s table and gnaw out those big holes, when I realized I could just print out a new panel with the holes already in place:

No muss, no fuss, no exciting chips… and no tedious corner filing, either.

The 3D model has the hole for an LED that I added later; the panel shown above acquired that hole during a brief conference with Mr Drill Press.

In actual point of fact, I had to do a bit of edge filing for the switches, as the holes came out slightly undersized. The HoleWindage setting should take care of that for the next time around. The panel was a drop-in replacement for the original: all the outside dimensions & thicknesses were spot on.

The OpenSCAD source code:

```// End panel for PacTec 61191-01 box
//    Panel 61580-01
// Ed Nisley - KE4ZNU - Feb 2011

Layer1Z = 1.50;
Layer2Z = 1.00;

HoleWindage = 0.55;                // approximately equal to extrusion width
Protrusion = 0.1;                // stick out over top and bottom

SwitchOffsetX = 15.0;

SwitchX = 16.0 + HoleWindage;
SwitchY = 12.0 + HoleWindage;
SwitchZ = Layer1Z + Layer2Z;

LedR = (5.0 + HoleWindage)/2;
LedZ = SwitchZ;

difference() {
union() {
translate([0,0,Layer1Z/2]) cube([55,22.5,Layer1Z],center=true);
translate([0,0,(Layer1Z + Layer2Z)/2]) cube([52.6,19.5,Layer1Z + Layer2Z],center=true);
}

translate([SwitchOffsetX,0,SwitchZ/2])
cube([SwitchX,SwitchY,SwitchZ + 2*Protrusion],center=true);

translate([-SwitchOffsetX,0,SwitchZ/2])
cube([SwitchX,SwitchY,SwitchZ + 2*Protrusion],center=true);

translate([0,0,LedZ/2])
cylinder(r=LedR,h=LedZ + 2*Protrusion,center=true,\$fn=10);

}
```

2 thoughts on “3D Printed Pactec Box Panel”

1. It’s going to take a good amount time for me to start seeing the world as it might be printed. Back when the cupcake was released I was trying to think of all the things that could be made so that I could justify buying it, yet despite knowing it would be awfully useful for something, I just could figure out what. If it weren’t for Thingiverse, I’m inclined to think that the extent of the capability of 3D printing would go unrecognized for most everybody.

1. Ed says:

Well, seeing that panel with two holes emerging as a finished object was something of an epiphany. I’ve been doing entirely too much fiddling with the obscene gerund printer and not nearly enough printing!

I plan to print near-net objects that can be machined to final shape / tolerance / finish on the Sherline. Most of what I build can be relatively low-strength printed ABS, so starting with a hunk that’s the right general size & shape seems like a major win.

Of course, for things that don’t require additional machining and which can tolerate a corrugated surface finish, 3D printing is just wonderful. The surface finish seems attractive, in a hand-carved / made-it-myself / not-mass-produced sort of way, and looks no worse than my usual botch jobs.

I also spend far too much time puzzling over fixtures: how to hold a part while gnawing on it. Using 3D printing to create quick-and-dirty fixtures seems like a win, as you can print a fixture that’s (very near?) the proper shape for a specific part, clamp the widget into the fixture, and proceed with milling / drilling / whatever.

The TOM is now extruding at 0.33 mm vertical and 0.56 mm horizontal. The nozzle pretty much determines the horizontal resolution and the bleeding edge of DIY printing seems to be using 0.35 mm nozzles with 1.75 mm filaments. For my purposes, that wouldn’t improve the resolution enough to make the effort worthwhile.

I wish searching Thingiverse was actually useful; I simply cannot find a specific object I know is out there…