DiscoVision Philips Code Test Disc

ohnoyoko · Posted: 06 Dec 2020, 04:36

Thanks! If I may ask, how long is GGV-129 each way, and do you know the approximate bar size? I ask because I could use the GGV-129 for some calibration I'm doing later this month. I hacked something together from a 3/16 (4mm) bar that I'm told should work. I'd just like to make sure that sounds reasonable. Judging by the photo, I should be using a thicker rod, but maybe I'm misjudging?

cplusplus · Posted: 06 Dec 2020, 05:09

Sure, see attached.

ohnoyoko · Posted: 06 Dec 2020, 08:52

Thanks! Very useful. Even if this doesn't get scanned, I think the measurements are enough that a 3D model could be created by hand.

ohnoyoko · Posted: 06 Dec 2020, 09:24

Oh, and would it be possible to get a measured, head-on shot of the tip of the tool? I think somebody posted one long ago but it didn't have measurements. Also, do you have a millimeter ruler? If not, no worries. Thanks either way!

simoni · Posted: 06 Dec 2020, 12:41

It's difficult to get an exact grip on something made in metric and measured roughly in inches but the following code will make something about right in OpenSCAD. I don't have the tool or the player, so I can't really do much more than guess:

Code: Select all

// Pioneer GGV-129 calibration tool

$fn=100;

// Define the shaft and tip as 2D profiles so they
// can be extruded (makes it possible to rotate_extrude
// the bend in the shaft)
module 2d_shaft_profile(diameter) 
{
    // Draw 2D circle with diameter of 5.5mm
    circle(r=diameter / 2);
}

module 2d_tip_profile(diameter)
{
    // Draw 2D circle with diameter of 1.5mm
    circle(r=diameter / 2);
}

module lower_shaft(diameter)
{
     translate([-(diameter*2),0,0]) rotate([90,0,0]) linear_extrude(75) {
        2d_shaft_profile(diameter);
    }
}

module upper_shaft(shaft_diameter, tip_diameter, tip_length)
{
    // Shaft
    translate([0,shaft_diameter * 2,0]) rotate([0,90,]) linear_extrude(36) {
        2d_shaft_profile(shaft_diameter);
    }

    // Tip
    translate([36,(shaft_diameter*2)+(shaft_diameter/2) - (1.5 / 2),0]) rotate([0,90,0]) linear_extrude(tip_length) {
        2d_tip_profile(tip_diameter);
    }
}

module shaft_bend(diameter)
{
    difference() {
        // Draw the whole ring
        rotate_extrude(convexity=10)
            translate([diameter * 2,0,0])
                2d_shaft_profile(diameter);

        // Remove the 3/4s we don't need
        dia2 = diameter * 2;
        translate([-dia2 + 1,-dia2,0]) cube([dia2*2,dia2*2,dia2], center=true);
        translate([dia2 - 1,-dia2,0]) cube([dia2*2,dia2*2,dia2], center=true);
        translate([dia2,dia2 - 1,0]) cube([dia2*2,dia2*2,dia2], center=true);
    }
}

module render_tool(shaft_diameter, tip_diameter, tip_length)
{
    lower_shaft(shaft_diameter);
    upper_shaft(shaft_diameter, tip_diameter, tip_length);
    shaft_bend(shaft_diameter);
}

render_tool(5, 1.5, 1.5);

Makes a shape like this:

Attachment:

File comment: OpenSCAD render

tool.png [ 37.97 KiB | Viewed 1003 times ]

I know OpenSCAD isn't obvious to all, but it should be easy to modify based on the comments etc.

/Simon

cplusplus · Posted: 06 Dec 2020, 15:42

Sorry it was late for me last night, and I couldn't find my ruler. Nevertheless, nice work Simon.

I'll be able to post measurements made with a digital caliper by Tuesday. I'll cut the heatshrink off beforehand since I think that was added by the tech.

cplusplus · Posted: 08 Dec 2020, 00:11

I removed the heatshrink.

Base is 5mm thick. Long part is 85mm, arm is 40mm (42mm with tip included).

Tip is 2mm thick, 2mm long.

In my photo of the three screwdrivers, the center one's pin is straight. On my GGV-129 it is bent. In Duncan's photo (here: Eccentric screwdriver) it does not look bent, so mine might be flawed.

simoni · Posted: 08 Dec 2020, 14:24

Here is the code updated with those measurements:

Code: Select all

// Pioneer GGV-129 calibration tool

$fn=100;

// Define the shaft and tip as 2D profiles so they
// can be extruded (makes it possible to rotate_extrude
// the bend in the shaft)
module 2d_shaft_profile(diameter) 
{
    // Draw 2D circle with specified diameter
    circle(r=diameter / 2);
}

module 2d_tip_profile(diameter)
{
    // Draw 2D circle with specified diameter
    circle(r=diameter / 2);
}

module lower_shaft(diameter)
{
     translate([-(diameter*2),0,0]) rotate([90,0,0]) linear_extrude(85) {
        2d_shaft_profile(diameter);
    }
}

module upper_shaft(shaft_diameter, tip_diameter, tip_length)
{
    // Shaft
    translate([0,shaft_diameter * 2,0]) rotate([0,90,]) linear_extrude(40) {
        2d_shaft_profile(shaft_diameter);
    }

    // Tip
    translate([40,(shaft_diameter*2)+(shaft_diameter/2) - (tip_diameter / 2),0]) rotate([0,90,0]) linear_extrude(tip_length) {
        2d_tip_profile(tip_diameter);
    }
}

module shaft_bend(diameter)
{
    difference() {
        // Draw the whole ring
        rotate_extrude(convexity=10)
            translate([diameter * 2,0,0])
                2d_shaft_profile(diameter);

        // Remove the 3/4s we don't need
        dia2 = diameter * 2;
        translate([-dia2 + 1,-dia2,0]) cube([dia2*2,dia2*2,dia2], center=true);
        translate([dia2 - 1,-dia2,0]) cube([dia2*2,dia2*2,dia2], center=true);
        translate([dia2,dia2 - 1,0]) cube([dia2*2,dia2*2,dia2], center=true);
    }
}

module render_tool(shaft_diameter, tip_diameter, tip_length)
{
    lower_shaft(shaft_diameter);
    upper_shaft(shaft_diameter, tip_diameter, tip_length);
    shaft_bend(shaft_diameter);
}

render_tool(5, 2, 2);

Thanks for clarifying it cplusplus. It's likely that it would be hard to print as-is (since round shapes are generally problematic). You can add a second parameter to the 2D circle commands such as $fn=6, which would cause the cylinders to become hexagonal though which would solve most of the problems.

The tip is still an issue though as it won't really be strong. I'd ether make a hollow space there so you could glue in some strong 2mm wire; or you could make it 1.75mm and just use a little bit of printer filament (ABS or PETG is probably strong enough).

DiscoVision Philips Code Test Disc

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