Tag: M2

Using and tweaking a Makergear M2 3D printer

Reticle Guide for Ruler Quilting

I made the pencil guides to help Mary design ruler quilting patterns, but sometimes she must line up the ruler with a feature on an existing pattern. To that end, we now have a reticle guide:

Ruler Adapters - pencil guide and reticle — Ruler Adapters – pencil guide and reticle

The general idea is that it’s easier to see the pattern on paper through the crosshair than through a small hole. You put the button over a feature, align the reticle, put the ruler against the button, replace it with pencil guide, and away you go.

The solid model looks much more lively than you’d expect:

Ruler Adapter - reticle - Slic3r preview — Ruler Adapter – reticle – Slic3r preview

Printing up a pair of each button produces the same surface finish as before; life is good!

The OpenSCAD source code as a GitHub Gist:

	// Quilting Ruler Adapters
	// Ed Nisley KE4ZNU October 2016

	//- Extrusion parameters must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———-
	// Dimensions

	ID = 0;
	OD = 1;
	LENGTH = 2;

	Offset = 0.25 * inch;

	Template = [2.0,2*Offset,3.0];

	NumSides = 16*4;
	HoleSides = 8;

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes
	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);
	FixDia = Dia / cos(180/Sides);
	cylinder(d=(FixDia + HoleWindage),h=Height,$fn=Sides);
	}


	//———-
	// Build them

	translate([-Template[OD],0,0])
	difference() {
	cylinder(d=Template[OD],h=Template[LENGTH],$fn=NumSides);
	translate([0,0,-Template[LENGTH]])
	PolyCyl(Template[ID],3*Template[LENGTH],HoleSides);
	translate([0,0,-Protrusion])
	cylinder(d1=2*Template[ID],d2=Template[ID],h=Template[LENGTH]/3 + Protrusion,$fn=HoleSides);
	translate([0,0,Template[LENGTH] + Protrusion])
	mirror([0,0,1])
	cylinder(d1=2*Template[ID],d2=Template[ID],h=Template[LENGTH]/3 + Protrusion,$fn=HoleSides);
	}

	translate([Template[OD],0,0])
	difference() {
	cylinder(d=Template[OD],h=Template[LENGTH],$fn=NumSides);
	for (a=[45,135])
	rotate(a)
	cube([0.70Template[OD],0.15Template[OD],3*Template[LENGTH]],center=true);
	}

view raw Ruler Adapters.scad hosted with ❤ by GitHub

2016-10-17

Pencil Guides for Ruler Quilting

Mary has been doing Ruler Quilting and wanted a pencil guide (similar to the machine’s ruler foot) to let her sketch layouts before committing stitches to fabric. The general idea is to offset the pencil by 1/4 inch from the edge of the ruler:

Ruler Adapter - solid model — Ruler Adapter – solid model

That was easy.

Print three to provide a bit of cooling time and let her pass ’em around at her next quilting bee:

Ruler Adapter - Slic3r preview — Ruler Adapter – Slic3r preview

Her favorite doodling pencil shoves a 0.9 mm lead through a 2 mm ferrule, so ream the center hole with a #44 drill (86 mil = 2.1 mm) to suit:

The outer perimeters have 64 facets, an unusually high number for my models, so they’re nice & smooth on the ruler. Even though I didn’t build them sequentially, they had zero perimeter zits and the OD came out 0.500 inch on the dot.

The chamfers guide the pencil point into the hole and provide a bit of relief for the pencil’s snout.

If I had a laser cutter, I could make special rulers for her, too …

The OpenSCAD source code as a GitHub Gist:

	// Quilting Ruler Adapters
	// Ed Nisley KE4ZNU October 2016

	//- Extrusion parameters must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———-
	// Dimensions

	ID = 0;
	OD = 1;
	LENGTH = 2;

	Offset = 0.25 * inch;

	Template = [2.0,2*Offset,3.0];

	NumSides = 16*4;
	HoleSides = 8;

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes
	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);
	FixDia = Dia / cos(180/Sides);
	cylinder(d=(FixDia + HoleWindage),h=Height,$fn=Sides);
	}


	//———-
	// Build it

	difference() {
	cylinder(d=Template[OD],h=Template[LENGTH],$fn=NumSides);
	translate([0,0,-Template[LENGTH]])
	PolyCyl(Template[ID],3*Template[LENGTH],HoleSides);
	translate([0,0,-Protrusion])
	cylinder(d1=2*Template[ID],d2=Template[ID],h=Template[LENGTH]/3 + Protrusion,$fn=HoleSides);
	translate([0,0,Template[LENGTH] + Protrusion])
	mirror([0,0,1])
	cylinder(d1=2*Template[ID],d2=Template[ID],h=Template[LENGTH]/3 + Protrusion,$fn=HoleSides);
	}

view raw Ruler Adapters.scad hosted with ❤ by GitHub

2016-10-13

Makergear M2: Spring-Loaded Extruder Feed Gear

When I installed the new fine-tooth filament drive gear (wheel, whatever) in the M2, I ran some numbers that suggested replacing the fixed-position screw with a (more-or-less-)constant-force spring. Some recent discussions on the M2 forum suggest, at least to me, that the drive gear is, indeed, less forgiving of filament diameter variations, drive housing wear, and suchlike than the chunkier old gear.

Having recently bought an assortment of longer M4 screws, I finally got around to installing an appropriate spring from the Big Box o’ Springs and another washer to capture it:

Makergear M2 – spring-loaded filament drive

Before doing anything, I measured the gap between the filament drive body (on the left) and the lever arm (on the right) holding the idler bearing: 21 mil = 0.53 mm.

I don’t have a number for the spring constant; it’s rather stiff.

After installing the spring, I cranked the screw to restore the same gap as before, which should mean the spring is exerting roughly the same force on the arm as the fixed-position screw.

The general idea: the spring allows the flexible arm to move as the filament diameter changes, while maintaining roughly the same pressure on the drive gear, thus producing nearly the same depth-of-engagement grooves in the filament. Maintaining “the same pressure” requires the motion to be relatively small compared to the spring preload distance, which seems reasonable with ±0.1 mm diameter variations and maybe 5 mm of preload.

The new filament drive gear hasn’t ever stripped out (after that initial finger fumble), so this will be more of a test to verify that the spring doesn’t make the situation worse.

2016-10-11
Vacuum Tube LEDs: Improved Sockets

All the sockets now sport channels in the bottom to capture the braid to the plate cap (whether or not the tube has a plate cap) and the wiring from the Arduino:

Vacuum Tube Lights – Octal Socket – solid model

The Slic3r preview shows the detail a bit better:

Vaccum Tube Lights – Octal Socket – Slic3r preview

The boss around the pins is now 25 mm OD and snaps neatly into the unpunched hub hole of a hard drive platter:

0D3 Octal – 25 mm socket OD in platter

I moved the mounting holes to 42 mm OC to give the button heads on those screws a bit more clearance from the base.

Moving the knockoff Neopixel up to the top of the pipe leading to the tube base dramatically increases the amount of light going into the tube envelope:

0D3 Octal – 25 mm socket – raised LED

You can just barely see a strip of foam tape holding the LED PCB (loosely) into the too-large hole.

The OpenSCAD source code also produces the improved base clamp; to get a socket, just set Layout = "Socket" and away you go. It doesn’t yet have the reduced-diameter hole down the middle; that’s in the nature of fine tuning.

2016-10-06
Vacuum Tube LEDs: Milling a 0D3 Spigot the Right Way

Now, with the 0D3 tube properly clamped and aligned in the Sherline mill:

OD3 Octal – V-block clamp

I can slowly run an end mill down onto the spigot:

0D3 Octal – milling spigot

Eventually converting the whole post into black dust in the vacuum cleaner:

0D3 Octal – milled spigot

That was completely uneventful, which is pretty much the whole point of good fixturing, isn’t it?

Applying the vacuum cleaner while milling seems to have kept the dust out of the base, although I’m not sure I can pull that trick off every time.

2016-10-05

Improved Octal Tube Base Clamp

In order to clamp the tube in a V-block, the clamp must position the tube’s centerline so the envelope will clear the V groove, thusly:

OD3 Octal - V-block clamp — OD3 Octal – V-block clamp

The clamp now extends into the V-block and surrounds the entire Bakelite tube base:

Octal base compression clamp - Slic3r preview — Octal base compression clamp – Slic3r preview

The little divot captures the clamp screw and the slot lets the whole affair compress just enough to firmly squeeze the entire tube base.

The tube data table now includes columns for the envelope OD and the base OD, although only the 0D3 (and similar) Octal tubes in my collection have a bulging envelope and a smaller base. You can build clamps for cylindrical glass tubes if you like; I don’t vouch for the accuracy of the table contents.

For whatever it’s worth, the 6SN7GTB tube I started with has a 32 mm Bakelite base and the 0D3 tube has a 29 mm base. That should probably justify two separate entries in the table, but I’m making this up as I go along.

The OpenSCAD source code as a GitHub Gist:

	// Vacuum Tube LED Lights
	// Ed Nisley KE4ZNU February … September 2016

	Layout = "TubeClamp"; // Cap LampBase USBPort Bushings
	// Socket(s) Cap (Build)FinCap Platter[Base\|Fixture]
	// TubeClamp PlatterParts
	DefaultSocket = "Octal";

	Section = false; // cross-section the object

	Support = true;

	//- Extrusion parameters must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———————-
	// Dimensions
	// https://en.wikipedia.org/wiki/Tube_socket#Summary_of_Base_Details
	// punch & screw OC modified for drive platter chassis plate
	// platter = 25 mm ID
	// CD = 15 mm ID with raised ring at 37 mm, needs screw head clearance

	T_NAME = 0; // common name
	T_NUMPINS = 1; // total, with no allowance for keying
	T_PINBCD = 2; // tube pin circle diameter
	T_PINOD = 3; // … diameter
	T_PINLEN = 4; // … length (must also clear evacuation tip / spigot)
	T_HOLEOD = 5; // nominal panel hole from various sources
	T_PUNCHOD = 6; // panel hole optimized for inch-size Greenlee punches
	T_BASEOD = 7; // base OD
	T_BULBOD = 8; // glass envelope OD
	T_PIPEOD = 9; // light pipe from LED to tube base (clear evac tip / spigot)
	T_SCREWOC = 10; // mounting screw holes
	T_PLATECAP = 11; // nonzero to print a plate cap

	// Name pins BCD dia length hole punch base bulb pipe screw cap
	TubeData = [
	["Mini7", 8, 9.53, 1.016, 7.0, 16.0, 25.0, 18.0, 18.0, 5.0, 35.0, 0], // punch 11/16, screw 22.5 OC
	// ["Octal", 8, 17.45, 2.36, 11.0, 36.2, (8 + 1)/8 * inch, 32.0, 38.1, 11.5, 47.0, 1], // screw 39.0 OC, base 32 or 39
	["Octal", 8, 17.45, 2.36, 11.0, 36.2, 25.0, 29.0, 38.1, 11.5, 42.0, 1], // platter + 4 mm screws
	["Noval", 10, 11.89, 1.1016, 7.0, 22.0, 25.0, 21.0, 21.0, 7.5, 35.0, 0], // punch 7/8, screw 28.0 OC
	["Magnoval", 10, 17.45, 1.27, 9.0, 29.7, (4 + 1)/4 * inch, 46.0, 46.0, 12.4, 38.2, 0], // similar to Novar
	// ["Duodecar", 13, 19.10, 1.05, 9.0, 32.0, (4 + 1)/4 * inch, 38.0, 38.0, 12.5, 47.0, 1], // screw was 39.0 OC
	["Duodecar", 13, 19.10, 1.05, 9.0, 25.0, 25.0, 38.0, 38.0, 12.5, 42.0, 1], // fit un-punched drive platter
	];

	ID = 0;
	OD = 1;
	LENGTH = 2;

	Pixel = [7.0,10.0,3.0]; // ID = contact patch, OD = PCB dia, LENGTH = overall thickness
	PixelRecessHeight = 1.55*Pixel[LENGTH]; // enough of a recess to allow for tube top curvature

	SocketNut = // socket mounting: threaded insert or nut recess
	// [3.5,5.2,7.2] // 6-32 insert
	[4.0,6.0,5.9] // 4 mm short insert
	;
	NutSides = 8;

	SocketShim = 2*ThreadThick; // between pin holes and pixel top
	SocketFlange = 1.5; // rim around socket below punchout
	PanelThick = 1.5; // socket extension through punchout

	FinCutterOD = 1/8 * inch;
	FinCapSize = [(Pixel[OD] + 2FinCutterOD),30.0,(10.0 + 2Pixel[LENGTH])];

	USBPCB =
	// [28,16,6.5] // small Sparkfun knockoff
	[36,18 + 1,5.8 + 0.4] // Deek-Robot fake FTDI with ISP header
	;

	Platter = [25.0,95.0,1.26]; // hard drive platter dimensions
	PlatterSides = 8*4; // polygon approximation

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes

	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);

	FixDia = Dia / cos(180/Sides);

	cylinder(d=(FixDia + HoleWindage),h=Height,$fn=Sides);
	}

	//———————-
	// Tube cap

	CapTube = [4.0,3/16 * inch,10.0]; // brass tube for flying lead to cap LED

	CapSize = [Pixel[ID],(Pixel[OD] + 2.0),(CapTube[OD] + 2.0*Pixel[LENGTH])];
	CapSides = 8*4;

	SkirtOD = CapSize[OD] + 4*ThreadWidth;

	CapTubeHeight = (CapSize[LENGTH] + PixelRecessHeight)/2;
	CapTubeBossOD = 1ThreadWidth + 2(CapTubeHeight – PixelRecessHeight)/cos(180/8);

	module Cap() {

	difference() {
	union() {
	cylinder(d=CapSize[OD],h=(CapSize[LENGTH]),$fn=CapSides); // main cap body
	translate([0,0,CapSize[LENGTH]]) // rounded top
	scale([1.0,1.0,0.65])
	sphere(d=CapSize[OD]/cos(180/CapSides),$fn=CapSides); // cos() fixes slight undersize vs cylinder
	cylinder(d1=SkirtOD,d2=CapSize[OD],h=PixelRecessHeight,$fn=CapSides); // skirt
	translate([0,-SkirtOD/2,CapTubeHeight]) // boss around brass tube
	rotate([-90,0,0])
	rotate(180/8)
	cylinder(d=CapTubeBossOD,h=CapTube[LENGTH],$fn=8);
	}

	translate([0,0,-Protrusion]) // bore for wiring to LED
	PolyCyl(CapSize[ID],(CapSize[LENGTH] + 3*ThreadThick + Protrusion),CapSides);

	translate([0,0,-Protrusion]) // PCB recess with clearance for tube dome
	PolyCyl(Pixel[OD],(PixelRecessHeight + Protrusion),CapSides);

	translate([0,0,(PixelRecessHeight – Protrusion)]) // small step + cone to retain PCB
	cylinder(d1=(Pixel[OD]/cos(180/CapSides) + HoleWindage),d2=Pixel[ID],h=(Pixel[LENGTH] + Protrusion),$fn=CapSides);

	translate([0,0,CapTubeHeight]) // hole for brass tube holding wire loom
	rotate([90,0,0]) rotate(180/8)
	PolyCyl(CapTube[OD],CapSize[OD],8);
	}

	}

	//———————-
	// Heatsink tube cap

	module FinCap() {

	CableOD = 3.5; // cable + braid diameter
	BulbOD = 3.75 * inch; // bulb OD; use 10 inches for flat

	echo(str("Fin Cutter: ",FinCutterOD));
	FinSides = 2*4;

	BulbRadius = BulbOD / 2;
	BulbDepth = BulbRadius – sqrt(pow(BulbRadius,2) – pow(FinCapSize[OD],2)/4);
	echo(str("Bulb OD: ",BulbOD," recess: ",BulbDepth));

	NumFins = floor(PIFinCapSize[ID] / (2FinCutterOD));
	FinAngle = 360 / NumFins;
	echo(str("NumFins: ",NumFins," angle: ",FinAngle," deg"));

	difference() {
	union() {
	cylinder(d=FinCapSize[ID],h=FinCapSize[LENGTH],$fn=2*NumFins); // main body

	for (i = [0:NumFins – 1]) // fins
	rotate(i * FinAngle)
	hull() {
	translate([FinCapSize[ID]/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	translate([(FinCapSize[OD] – FinCutterOD)/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	}

	rotate(FinAngle/2) // cable entry boss
	translate([FinCapSize[ID]/2,0,FinCapSize[LENGTH]/2])
	cube([FinCapSize[OD]/4,FinCapSize[OD]/4,FinCapSize[LENGTH]],center=true);
	}

	for (i = [1:NumFins – 1]) // fin inner gullets, omit cable entry side
	rotate(i * FinAngle + FinAngle/2) // joint isn't quite perfect, but OK
	translate([FinCapSize[ID]/2,0,-Protrusion])
	rotate(0*180/FinSides)
	cylinder(d=FinCutterOD/cos(180/FinSides),h=(FinCapSize[LENGTH] + 2*Protrusion),$fn=FinSides);

	translate([0,0,-Protrusion]) // PCB recess
	PolyCyl(Pixel[OD],(PixelRecessHeight + Protrusion),FinSides);

	PolyCyl(Pixel[ID],(FinCapSize[LENGTH] – 3*ThreadThick),FinSides); // bore for LED wiring

	translate([0,0,(FinCapSize[LENGTH] – 3ThreadThick – 2CableOD/(2*cos(180/8)))]) // cable inlet
	rotate(FinAngle/2) rotate([0,90,0]) rotate(180/8)
	PolyCyl(CableOD,FinCapSize[OD],8);

	if (BulbOD <= 10.0 * inch) // curve for top of bulb
	translate([0,0,-(BulbRadius – BulbDepth + 2*ThreadThick)]) // … slightly flatten tips
	sphere(d=BulbOD,$fn=16*FinSides);
	}

	}


	//———————-
	// Aperture for USB-to-serial adapter snout
	// These are all magic numbers, of course

	module USBPort() {

	translate([0,USBPCB[0]])
	rotate([90,0,0])
	linear_extrude(height=USBPCB[0])
	polygon(points=[
	[0,0],
	[USBPCB[1]/2,0],
	[USBPCB[1]/2,0.5*USBPCB[2]],
	[USBPCB[1]/3,USBPCB[2]],
	[-USBPCB[1]/3,USBPCB[2]],
	[-USBPCB[1]/2,0.5*USBPCB[2]],
	[-USBPCB[1]/2,0],
	]);
	}


	//———————-
	// Box for Leviton ceramic lamp base

	module LampBase() {

	Insert = [3.5,5.2,7.2]; // 6-32 brass insert to match standard electrical screws

	Bottom = 3.0;
	Base = [4.0inch,4.5inch,20.0 + Bottom];
	Sides = 12*4;

	Retainer = [3.5,11.0,1.0]; // flat fiber washer holding lamp base screws in place

	StudSides = 8;
	StudOC = 3.5 * inch;
	Stud = [Insert[OD], // insert for socket screws
	min(15.0,1.5*(Base[ID] – StudOC)/cos(180/StudSides)), // OD = big enough to merge with walls
	(Base[LENGTH] – Retainer[LENGTH])]; // leave room for retainer


	union() {
	difference() {
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	rotate(180/Sides)
	translate([0,0,Bottom])
	cylinder(d=Base[ID],h=Base[LENGTH],$fn=Sides);
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount on double-sided foam tape
	rotate(0)
	USBPort();
	}
	for (i = [-1,1])
	translate([i*StudOC/2,0,0])
	rotate(180/StudSides)
	difference() {
	cylinder(d=Stud[OD],h=Stud[LENGTH],$fn=StudSides);
	translate([0,0,Bottom])
	PolyCyl(Stud[ID],(Stud[LENGTH] – (Bottom – Protrusion)),6);
	}
	}
	}

	//———————-
	// Base for hard drive platters

	module PlatterBase(TubeName = DefaultSocket) {

	PCB =
	[36,18,3] // Arduino Pro Mini
	;

	Tube = search([TubeName],TubeData,1,0)[0];
	SocketHeight = Pixel[LENGTH] + SocketShim + TubeData[Tube][T_PINLEN] – PanelThick;

	echo(str("Base for ",TubeData[Tube][0]," socket"));

	Overhang = 5.5; // platter overhangs base by this much

	Bottom = 4*ThreadThick;
	Base = [(Platter[OD] – 3*Overhang), // smaller than 3.5 inch Sch 40 PVC pipe…
	(Platter[OD] – 2*Overhang),
	2.0 + max(PCB[1],(2.0 + SocketHeight + USBPCB[2])) + Bottom];
	Sides = 24*4;

	echo(str(" Height: ",Base[2]," mm"));

	Insert = // platter mounting: threaded insert or nut recess
	// [3.5,5.2,7.2] // 6-32 insert
	[3.7,5.0,8.0] // 3 mm – long insert
	;

	NumStuds = 4;
	StudSides = 8;
	Stud = [Insert[OD], // insert for socket screws
	2*Insert[OD], // OD = big enough to merge with walls
	Base[LENGTH]]; // leave room for retainer
	StudBCD = floor(Base[OD] – Stud[OD]/cos(180/StudSides));
	echo(str("Platter screw BCD: ",StudBCD," mm"));

	PCBInset = Base[ID]/2 – sqrt(pow(Base[ID]/2,2) – pow(PCB[0],2)/4);

	union() {
	difference() {
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	rotate(180/Sides)
	translate([0,0,Bottom])
	cylinder(d=Base[ID],h=Base[LENGTH],$fn=Sides);
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount PCB on foam tape
	rotate(0)
	USBPort();
	}

	for (a = [0:(NumStuds – 1)]) // platter mounting studs
	rotate(180/NumStuds + a*360/(NumStuds))
	translate([StudBCD/2,0,0])
	difference() {
	rotate(180/(2*StudSides))
	cylinder(d=Stud[OD],h=Stud[LENGTH],$fn=2*StudSides);
	translate([0,0,Bottom])
	rotate(180/StudSides)
	PolyCyl(Stud[ID],(Stud[LENGTH] – (Bottom – Protrusion)),StudSides);
	}

	intersection() { // microcontroller PCB mounting plate
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	translate([-PCB[0]/2,(Base[ID]/2 – PCBInset),0])
	cube([PCB[0],Base[OD]/2,Base[LENGTH]],center=false);
	}

	difference() {
	intersection() { // totally ad-hoc bridge around USB opening
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	translate([-1.25*USBPCB[1]/2,-(Base[ID]/2),0])
	cube([1.25*USBPCB[1],2.0,Base[LENGTH]],center=false);
	}
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount PCB on foam tape
	rotate(0)
	USBPort();

	translate([0,-(Base[ID]/2 – 2.0 + 1ThreadWidth),Bottom – 3ThreadThick]) // legend
	rotate([90,0,180])
	linear_extrude(height=1*ThreadWidth + Protrusion) {
	translate([0,(Base[LENGTH] – 5.5),0])
	text(text=TubeName,size=4,font="Arial:style=Bold",halign="center");
	// translate([0,(Base[LENGTH] – 8.5),0])
	// text(text=str("BCD ",StudBCD),size=2,font="Arial",halign="center");
	translate([0,(Base[LENGTH] – 11),0])
	text(text="KE4ZNU",size=3,font="Arial",halign="center");
	}

	}
	}
	}


	//———————-
	// Drilling fixture for disk platters

	module PlatterFixture() {

	StudOC = [1.16inch,1.16inch]; // Sherline tooling plate screw spacing
	StudClear = 5.0;

	AlignOffset = 100;
	AlignBar = [3ThreadWidth,10.0,3ThreadThick];

	BasePlate = [(20 + StudOC[0]*ceil(Platter[OD] / StudOC[0])),(Platter[OD] + 10),7.0];
	PlateRound = 10.0; // corner radius

	difference() {
	hull() // basic block
	for (i=[-1,1], j=[-1,1])
	translate([i(BasePlate[0]/2 – PlateRound),j(BasePlate[1]/2 – PlateRound),0])
	cylinder(r=PlateRound,h=BasePlate[2],$fn=4*4);

	for (i=[-1,1], j=[-1,1]) // index marks
	translate([iAlignOffset/2,jAlignOffset/2,BasePlate[2] – 2*ThreadThick])
	cylinder(d=1.5,h=1,$fn=6);

	for (i=[-1,1])
	translate([i*(AlignOffset + AlignBar[0])/2,0,(BasePlate[2] – AlignBar[2]/2 + Protrusion/2)])
	cube(AlignBar + [0,0,Protrusion],center=true);

	for (j=[-1,1])
	translate([0,j*(AlignOffset + AlignBar[0])/2,(BasePlate[2] – AlignBar[2]/2 + Protrusion/2)])
	rotate(90)
	cube(AlignBar + [0,0,Protrusion],center=true);

	for (a=[0:90:270])
	rotate(a)
	translate([(AlignBar[1]/2 + AlignBar[0]/2),0,(BasePlate[2] – AlignBar[2]/2 + Protrusion/2)])
	cube(AlignBar + [0,-Protrusion,Protrusion],center=true);

	for (i=[-1,1], j=[-1,0,1]) // holes for tooling plate studs
	translate([iStudOC[0]ceil(Platter[OD] / StudOC[0])/2,j*StudOC[0],-Protrusion])
	PolyCyl(StudClear,BasePlate[2] + 2*Protrusion,6);

	translate([0,0,-Protrusion]) // center clamp hole
	PolyCyl(StudClear,BasePlate[2] + 2*Protrusion,6);

	translate([0,0,BasePlate[2] – Platter[LENGTH]]) // disk locating recess
	rotate(180/PlatterSides)
	linear_extrude(height=(Platter[LENGTH] + Protrusion),convexity=2)
	difference() {
	circle(d=(Platter[OD] + 1),$fn=PlatterSides);
	circle(d=Platter[ID],$fn=PlatterSides);
	}

	translate([0,0,BasePlate[2] – 4.0]) // drilling recess
	rotate(180/PlatterSides)
	linear_extrude(height=(4.0 + Protrusion),convexity=2)
	difference() {
	circle(d=(Platter[OD] – 10),$fn=PlatterSides);
	circle(d=(Platter[ID] + 10),$fn=PlatterSides);
	}
	}

	}

	//———————-
	// Tube Socket

	module Socket(Name = DefaultSocket) {

	NumSides = 6*4;

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," socket"));
	echo(str(" Punch: ",TubeData[Tube][T_PUNCHOD]," mm = ",TubeData[Tube][T_PUNCHOD]/inch," inch"));
	echo(str(" Screws: ",TubeData[Tube][T_SCREWOC]," mm =",TubeData[Tube][T_SCREWOC]/inch," inch OC"));

	OAH = Pixel[LENGTH] + SocketShim + TubeData[Tube][T_PINLEN];
	BaseHeight = OAH – PanelThick;

	difference() {
	union() {
	linear_extrude(height=BaseHeight) // base outline
	hull() {
	circle(d=(TubeData[Tube][T_PUNCHOD] + 2*SocketFlange),$fn=NumSides);
	for (i=[-1,1])
	translate([i*TubeData[Tube][T_SCREWOC]/2,0])
	circle(d=2.0*SocketNut[OD],$fn=NumSides);
	}
	cylinder(d=TubeData[Tube][T_PUNCHOD],h=OAH,$fn=NumSides); // boss in chassis punch hole
	}

	for (i=[0:(TubeData[Tube][T_NUMPINS] – 1)]) // tube pins
	rotate(i*360/TubeData[Tube][T_NUMPINS])
	translate([TubeData[Tube][T_PINBCD]/2,0,(OAH – TubeData[Tube][T_PINLEN])])
	rotate(180/4)
	PolyCyl(TubeData[Tube][T_PINOD],(TubeData[Tube][T_PINLEN] + Protrusion),4);

	for (i=[-1,1]) // mounting screw holes & nut traps / threaded inserts
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,-Protrusion]) {
	PolyCyl(SocketNut[OD],(SocketNut[LENGTH] + Protrusion),NutSides);
	PolyCyl(SocketNut[ID],(OAH + 2*Protrusion),NutSides);
	}

	translate([0,0,-Protrusion]) { // LED recess
	PolyCyl(Pixel[OD],(Pixel[LENGTH] + Protrusion),8);
	}

	translate([0,0,(Pixel[LENGTH] – Protrusion)]) { // light pipe
	rotate(180/TubeData[Tube][T_NUMPINS])
	PolyCyl(TubeData[Tube][T_PIPEOD],(OAH + 2*Protrusion),TubeData[Tube][T_NUMPINS]);
	}

	for (i=[-1,1]) // cable retaining slots
	translate([i*(Pixel[OD] + TubeData[Tube][T_SCREWOC])/4,0,(Pixel[LENGTH] – Protrusion)/2])
	cube([Pixel[LENGTH],TubeData[Tube][T_SCREWOC],(Pixel[LENGTH] + Protrusion)],center=true);
	}

	// Totally ad-hoc support structures …

	if (Support) {
	color("Yellow") {
	for (i=[-1,1]) // nut traps
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,(SocketNut[LENGTH] – ThreadThick)/2])
	for (a=[0:5])
	rotate(a*30 + 15)
	cube([2ThreadWidth,0.9SocketNut[OD],(SocketNut[LENGTH] – ThreadThick)],center=true);

	if (Pixel[OD] > TubeData[Tube][T_PIPEOD]) // support pipe only if needed
	translate([0,0,(Pixel[LENGTH] – ThreadThick)/2])
	for (a=[0:7])
	rotate(a*22.5)
	cube([2ThreadWidth,0.9Pixel[OD],(Pixel[LENGTH] – ThreadThick)],center=true);
	}
	}
	}


	//———————-
	// Greenlee punch bushings

	module PunchBushing(Name = DefaultSocket) {

	PunchScrew = 9.5;
	BushingThick = 3.0;

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," bushing"));

	NumSides = 6*4;

	difference() {
	union() {
	cylinder(d=Platter[ID],h=BushingThick,$fn=NumSides);
	cylinder(d=TubeData[Tube][T_PUNCHOD],h=(BushingThick – Platter[LENGTH]),$fn=NumSides);
	}
	translate([0,0,-Protrusion])
	PolyCyl(PunchScrew,5.0,8);
	}
	}

	//———————-
	// Tube clamp

	module TubeClamp(Name = DefaultSocket) {

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," clamp"));

	ClampWidth = 37.0; // inside of clamp arch
	ClampLength = 20; // along tube base

	ClampScrew = [6.0,7.8,6.0]; // nose of clamp screw

	ClampBlock = [4*ThreadWidth + TubeData[Tube][T_BULBOD],
	4*ThreadWidth + TubeData[Tube][T_BULBOD],
	ClampLength];

	difference() {
	union() {
	intersection() {
	translate([0,0,ClampBlock[2]/2])
	rotate(45)
	cube(ClampBlock,center=true); // V-block sides
	translate([0,-ClampWidth/2,ClampBlock[2]/2])
	cube([ClampWidth,ClampWidth,ClampBlock[2]],center=true); // clamp sides
	}
	intersection() {
	cylinder(d=ClampWidth,h=ClampBlock[2]);
	translate([0,ClampWidth/4,ClampBlock[2]/2])
	cube([ClampWidth,ClampWidth/2,ClampBlock[2]],center=true); // clamp sides
	}
	}
	translate([0,0,-Protrusion]) // remove tube base (remains centered)
	cylinder(d=TubeData[Tube][T_BASEOD],h=(ClampLength + 2*Protrusion));
	translate([0,(ClampWidth/2 + TubeData[Tube][T_BASEOD]/2)/2,ClampBlock[LENGTH]/3])
	rotate([-90,0,0])
	PolyCyl(ClampScrew[ID],1*ClampScrew[LENGTH],6); // clamp screw recess
	translate([0,-(6*ThreadWidth)/2,-Protrusion])
	cube([ClampWidth,6ThreadWidth,(ClampLength + 2Protrusion)]); // clamp relief slot
	}

	}

	//———————-
	// Build it

	if (Layout == "Cap") {
	if (Section)
	difference() {
	Cap();
	translate([-CapSize[OD],0,CapSize[LENGTH]])
	cube([2CapSize[OD],2CapSize[OD],3*CapSize[LENGTH]],center=true);
	}
	else
	Cap();
	}

	if (Layout == "FinCap") {
	if (Section) render(convexity=5)
	difference() {
	FinCap();
	// translate([0,-FinCapSize[OD],FinCapSize[LENGTH]])
	// cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	translate([-FinCapSize[OD],0,FinCapSize[LENGTH]])
	cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	}
	else
	FinCap();
	}

	if (Layout == "BuildFinCap")
	translate([0,0,FinCapSize[LENGTH]])
	rotate([180,0,0])
	FinCap();

	if (Layout == "LampBase")
	LampBase();

	if (Layout == "PlatterBase")
	PlatterBase();

	if (Layout == "PlatterParts") {
	Tube = search([DefaultSocket],TubeData,1,0)[0];
	echo(str("Parts for ",TubeData[Tube][T_NAME]," assembly"));
	PlatterBase();
	translate([0.25Platter[OD],-0.6Platter[OD],0])
	rotate(0)
	Socket();
	if (TubeData[Tube][T_PLATECAP])
	for (i=[-1,1])
	translate([(-0.25Platter[OD] – iPixel[OD]),-0.6*Platter[OD],0])
	rotate(i*90)
	Cap();
	}

	if (Layout == "PlatterFixture")
	PlatterFixture();

	if (Layout == "USBPort")
	USBPort();

	if (Layout == "TubeClamp")
	TubeClamp();

	if (Layout == "Bushings")
	PunchBushing();

	if (Layout == "Socket")
	if (Section) {
	difference() {
	Socket();
	translate([-100/2,0,-Protrusion])
	cube([100,50,50],center=false);
	}
	}
	else
	Socket();

	if (Layout == "Sockets") {
	translate([0,50,0])
	Socket("Mini7");
	translate([0,20,0])
	Socket("Octal");
	translate([0,-15,0])
	Socket("Duodecar");
	translate([0,-50,0])
	Socket("Noval");
	translate([0,-85,0])
	Socket("Magnoval");}

view raw Vacuum Tube Lights.scad hosted with ❤ by GitHub

2016-10-04

Octal Tube Base Clamp

One of the octal tubes in my collection has a broken spigot / key post that lets some light in through the bottom of the normally opaque Bakelite base:

Octal socket in CD - LED diffraction — Octal socket in CD – LED diffraction

Perhaps drilling out the base would let more light pass around the evacuation tip, but that requires a shell drill to clear the tip. Some doodling suggested a drill with 12 mm OD and 8 mm ID, which was close enough to one of the smaller homebrew drills in my collection that I decided to see how it worked:

You (well, I) can’t freehand such a hole, particularly with a glass tip in the middle, so I needed a way to clamp the tube in either the drill press or the Sherline. A pad for the clamp screw in a V-block seemed appropriate:

Vacuum Tube Lights - Octal base clamp - Slic3r preview — Vacuum Tube Lights – Octal base clamp – Slic3r preview

The screw hole sits at the 1/3 point to put more pressure near the pin end of the base. Maybe that matters.

The setup looks like this, with a small red laser dot near the front of the base:

The tube rests on a random scrap of plastic, with the hope that the drill won’t apply enough pressure to break the glass envelope.

In normal use, the V-block would be oriented the other way to let you cross-drill the cylinder. In this end-on orientation, drilling torque can rotate the tube; compliant padding for more traction may be in order.

The OpenSCAD source code as a GitHub Gist now includes a module that spits out the clamp:

	// Vacuum Tube LED Lights
	// Ed Nisley KE4ZNU February … September 2016

	Layout = "TubeClamp"; // Cap LampBase USBPort Bushings
	// Socket(s) Cap (Build)FinCap Platter[Base\|Fixture]
	// TubeClamp
	DefaultSocket = "Mini7";

	Section = false; // cross-section the object

	Support = true;

	//- Extrusion parameters must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———————-
	// Dimensions
	// https://en.wikipedia.org/wiki/Tube_socket#Summary_of_Base_Details
	// punch & screw OC modified for drive platter chassis plate
	// platter = 25 mm ID
	// CD = 15 mm ID with raised ring at 37 mm, needs screw head clearance

	T_NAME = 0; // common name
	T_NUMPINS = 1; // total, with no allowance for keying
	T_PINBCD = 2; // tube pin circle diameter
	T_PINOD = 3; // … diameter
	T_PINLEN = 4; // … length (must also clear evacuation tip / spigot)
	T_HOLEOD = 5; // nominal panel hole from various sources
	T_PUNCHOD = 6; // panel hole optimized for inch-size Greenlee punches
	T_TUBEOD = 7; // envelope or base diameter
	T_PIPEOD = 8; // light pipe from LED to tube base (clear evac tip / spigot)
	T_SCREWOC = 9; // mounting screw holes

	// Name pins BCD dia length hole punch tube pipe screw
	TubeData = [
	["Mini7", 8, 9.53, 1.016, 7.0, 16.0, 25.0, 18.0, 5.0, 35.0], // punch 11/16, screw 22.5 OC
	// ["Octal", 8, 17.45, 2.36, 11.0, 36.2, (8 + 1)/8 * inch, 32.0, 11.5, 47.0], // screw 39.0 OC
	["Octal", 8, 17.45, 2.36, 11.0, 36.2, 25.0, 32.0, 11.5, 42.0], // platter + 4 mm screws
	["Noval", 10, 11.89, 1.1016, 7.0, 22.0, 25.0, 21.0, 7.5, 35.0], // punch 7/8, screw 28.0 OC
	["Magnoval", 10, 17.45, 1.27, 9.0, 29.7, (4 + 1)/4 * inch, 46.0, 12.4, 38.2], // similar to Novar
	// ["Duodecar", 13, 19.10, 1.05, 9.0, 32.0, (4 + 1)/4 * inch, 38.0, 12.5, 47.0], // screw was 39.0 OC
	["Duodecar", 13, 19.10, 1.05, 9.0, 25.0, 25.0, 38.0, 12.5, 42.0], // fit un-punched drive platter
	];

	ID = 0;
	OD = 1;
	LENGTH = 2;

	Pixel = [7.0,10.0,3.0]; // ID = contact patch, OD = PCB dia, LENGTH = overall thickness

	SocketNut = // socket mounting: threaded insert or nut recess
	// [3.5,5.2,7.2] // 6-32 insert
	[4.0,6.0,5.9] // 4 mm short insert
	;
	NutSides = 8;

	SocketShim = 2*ThreadThick; // between pin holes and pixel top
	SocketFlange = 1.5; // rim around socket below punchout
	PanelThick = 1.5; // socket extension through punchout

	FinCutterOD = 1/8 * inch;
	FinCapSize = [(Pixel[OD] + 2FinCutterOD),30.0,(10.0 + 2Pixel[LENGTH])];

	USBPCB =
	// [28,16,6.5] // small Sparkfun knockoff
	[36,18 + 1,5.8 + 0.4] // Deek-Robot fake FTDI with ISP header
	;

	Platter = [25.0,95.0,1.26]; // hard drive platter dimensions

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes

	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);

	FixDia = Dia / cos(180/Sides);

	cylinder(d=(FixDia + HoleWindage),h=Height,$fn=Sides);
	}

	//———————-
	// Tube cap

	CapTube = [4.0,3/16 * inch,10.0]; // brass tube for flying lead to cap LED

	CapSize = [Pixel[ID],(Pixel[OD] + 2.0),(CapTube[OD] + 2*Pixel[LENGTH])];

	CapSides = 8*4;

	module Cap() {

	difference() {
	union() {
	cylinder(d=CapSize[OD],h=(CapSize[LENGTH]),$fn=CapSides); // main cap body
	translate([0,0,CapSize[LENGTH]]) // rounded top
	scale([1.0,1.0,0.65])
	sphere(d=CapSize[OD]/cos(180/CapSides),$fn=CapSides); // cos() fixes slight undersize vs cylinder
	cylinder(d1=(CapSize[OD] + 23ThreadWidth),d2=CapSize[OD],h=1.5*Pixel[LENGTH],$fn=CapSides); // skirt
	}

	translate([0,0,-Protrusion]) // bore for wiring to LED
	PolyCyl(CapSize[ID],(CapSize[LENGTH] + 3*ThreadThick + Protrusion),CapSides);

	translate([0,0,-Protrusion]) // PCB recess with clearance for tube dome
	PolyCyl(Pixel[OD],(1.5*Pixel[LENGTH] + Protrusion),CapSides);

	translate([0,0,(1.5*Pixel[LENGTH] – Protrusion)]) // small step + cone to retain PCB
	cylinder(d1=(Pixel[OD]/cos(180/CapSides) + HoleWindage),d2=Pixel[ID],h=(Pixel[LENGTH] + Protrusion),$fn=CapSides);

	translate([0,0,(CapSize[LENGTH] – CapTube[OD]/(2*cos(180/8)))]) // hole for brass tube holding wire loom
	rotate([90,0,0]) rotate(180/8)
	PolyCyl(CapTube[OD],CapSize[OD],8);
	}

	}

	//———————-
	// Heatsink tube cap

	module FinCap() {

	CableOD = 3.5; // cable + braid diameter
	BulbOD = 3.75 * inch; // bulb OD; use 10 inches for flat

	echo(str("Fin Cutter: ",FinCutterOD));
	FinSides = 2*4;

	BulbRadius = BulbOD / 2;
	BulbDepth = BulbRadius – sqrt(pow(BulbRadius,2) – pow(FinCapSize[OD],2)/4);
	echo(str("Bulb OD: ",BulbOD," recess: ",BulbDepth));

	NumFins = floor(PIFinCapSize[ID] / (2FinCutterOD));
	FinAngle = 360 / NumFins;
	echo(str("NumFins: ",NumFins," angle: ",FinAngle," deg"));

	difference() {
	union() {
	cylinder(d=FinCapSize[ID],h=FinCapSize[LENGTH],$fn=2*NumFins); // main body

	for (i = [0:NumFins – 1]) // fins
	rotate(i * FinAngle)
	hull() {
	translate([FinCapSize[ID]/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	translate([(FinCapSize[OD] – FinCutterOD)/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	}

	rotate(FinAngle/2) // cable entry boss
	translate([FinCapSize[ID]/2,0,FinCapSize[LENGTH]/2])
	cube([FinCapSize[OD]/4,FinCapSize[OD]/4,FinCapSize[LENGTH]],center=true);
	}

	for (i = [1:NumFins – 1]) // fin inner gullets, omit cable entry side
	rotate(i * FinAngle + FinAngle/2) // joint isn't quite perfect, but OK
	translate([FinCapSize[ID]/2,0,-Protrusion])
	rotate(0*180/FinSides)
	cylinder(d=FinCutterOD/cos(180/FinSides),h=(FinCapSize[LENGTH] + 2*Protrusion),$fn=FinSides);

	translate([0,0,-Protrusion]) // PCB recess
	PolyCyl(Pixel[OD],(1.5*Pixel[LENGTH] + Protrusion),FinSides);

	PolyCyl(Pixel[ID],(FinCapSize[LENGTH] – 3*ThreadThick),FinSides); // bore for LED wiring

	translate([0,0,(FinCapSize[LENGTH] – 3ThreadThick – 2CableOD/(2*cos(180/8)))]) // cable inlet
	rotate(FinAngle/2) rotate([0,90,0]) rotate(180/8)
	PolyCyl(CableOD,FinCapSize[OD],8);

	if (BulbOD <= 10.0 * inch) // curve for top of bulb
	translate([0,0,-(BulbRadius – BulbDepth + 2*ThreadThick)]) // … slightly flatten tips
	sphere(d=BulbOD,$fn=16*FinSides);
	}

	}


	//———————-
	// Aperture for USB-to-serial adapter snout
	// These are all magic numbers, of course

	module USBPort() {

	translate([0,USBPCB[0]])
	rotate([90,0,0])
	linear_extrude(height=USBPCB[0])
	polygon(points=[
	[0,0],
	[USBPCB[1]/2,0],
	[USBPCB[1]/2,0.5*USBPCB[2]],
	[USBPCB[1]/3,USBPCB[2]],
	[-USBPCB[1]/3,USBPCB[2]],
	[-USBPCB[1]/2,0.5*USBPCB[2]],
	[-USBPCB[1]/2,0],
	]);
	}


	//———————-
	// Box for Leviton ceramic lamp base

	module LampBase() {

	Insert = [3.5,5.2,7.2]; // 6-32 brass insert to match standard electrical screws

	Bottom = 3.0;
	Base = [4.0inch,4.5inch,20.0 + Bottom];
	Sides = 12*4;

	Retainer = [3.5,11.0,1.0]; // flat fiber washer holding lamp base screws in place

	StudSides = 8;
	StudOC = 3.5 * inch;
	Stud = [Insert[OD], // insert for socket screws
	min(15.0,1.5*(Base[ID] – StudOC)/cos(180/StudSides)), // OD = big enough to merge with walls
	(Base[LENGTH] – Retainer[LENGTH])]; // leave room for retainer


	union() {
	difference() {
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	rotate(180/Sides)
	translate([0,0,Bottom])
	cylinder(d=Base[ID],h=Base[LENGTH],$fn=Sides);
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount on double-sided foam tape
	rotate(0)
	USBPort();
	}
	for (i = [-1,1])
	translate([i*StudOC/2,0,0])
	rotate(180/StudSides)
	difference() {
	cylinder(d=Stud[OD],h=Stud[LENGTH],$fn=StudSides);
	translate([0,0,Bottom])
	PolyCyl(Stud[ID],(Stud[LENGTH] – (Bottom – Protrusion)),6);
	}
	}
	}

	//———————-
	// Base for hard drive platters

	module PlatterBase(TubeName = DefaultSocket) {

	PCB =
	[36,18,3] // Arduino Pro Mini
	;

	Tube = search([TubeName],TubeData,1,0)[0];
	SocketHeight = Pixel[LENGTH] + SocketShim + TubeData[Tube][T_PINLEN] – PanelThick;

	echo(str("Base for ",TubeData[Tube][0]," socket"));

	Overhang = 5.5; // platter overhangs base by this much

	Bottom = 4*ThreadThick;
	Base = [(Platter[OD] – 3*Overhang), // smaller than 3.5 inch Sch 40 PVC pipe…
	(Platter[OD] – 2*Overhang),
	2.0 + max(PCB[1],(2.0 + SocketHeight + USBPCB[2])) + Bottom];
	Sides = 24*4;

	echo(str(" Height: ",Base[2]," mm"));

	Insert = // platter mounting: threaded insert or nut recess
	// [3.5,5.2,7.2] // 6-32 insert
	[3.9,5.0,8.0] // 3 mm – long insert
	;

	NumStuds = 4;
	StudSides = 8;
	Stud = [Insert[OD], // insert for socket screws
	2*Insert[OD], // OD = big enough to merge with walls
	Base[LENGTH]]; // leave room for retainer
	StudBCD = floor(Base[ID] – Stud[OD] + (Stud[OD] – Stud[ID])/2);
	echo(str("Platter screw BCD: ",StudBCD," mm"));

	PCBInset = Base[ID]/2 – sqrt(pow(Base[ID]/2,2) – pow(PCB[0],2)/4);

	union() {
	difference() {
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	rotate(180/Sides)
	translate([0,0,Bottom])
	cylinder(d=Base[ID],h=Base[LENGTH],$fn=Sides);
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount PCB on foam tape
	rotate(0)
	USBPort();
	}

	for (a = [0:(NumStuds – 1)]) // platter mounting studs
	rotate(180/NumStuds + a*360/(NumStuds))
	translate([StudBCD/2,0,0])
	rotate(180/StudSides)
	difference() {
	cylinder(d=Stud[OD],h=Stud[LENGTH],$fn=2*StudSides);
	translate([0,0,Bottom])
	PolyCyl(Stud[ID],(Stud[LENGTH] – (Bottom – Protrusion)),StudSides);
	}

	intersection() { // microcontroller PCB mounting plate
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	translate([-PCB[0]/2,(Base[ID]/2 – PCBInset),0])
	cube([PCB[0],Base[OD]/2,Base[LENGTH]],center=false);
	}

	difference() {
	intersection() { // totally ad-hoc bridge around USB opening
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	translate([-1.25*USBPCB[1]/2,-(Base[ID]/2),0])
	cube([1.25*USBPCB[1],2.0,Base[LENGTH]],center=false);
	}
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount PCB on foam tape
	rotate(0)
	USBPort();

	translate([0,-(Base[ID]/2 – 2.0 + 1ThreadWidth),Bottom – 3ThreadThick]) // legend
	rotate([90,0,180])
	linear_extrude(height=1*ThreadWidth + Protrusion) {
	translate([0,(Base[LENGTH] – 5.5),0])
	text(text=TubeName,size=4,font="Arial:style=Bold",halign="center");
	// translate([0,(Base[LENGTH] – 8.5),0])
	// text(text=str("BCD ",StudBCD),size=2,font="Arial",halign="center");
	translate([0,(Base[LENGTH] – 11),0])
	text(text="KE4ZNU",size=3,font="Arial",halign="center");
	}

	}
	}
	}


	//———————-
	// Drilling fixture for disk platters

	module PlatterFixture() {

	StudOC = [1.16inch,1.16inch]; // Sherline tooling plate screw spacing
	StudClear = 5.0;

	BasePlate = [(20 + StudOC[0]*ceil(Platter[OD] / StudOC[0])),(Platter[OD] + 10),7.0];
	PlateRound = 10.0; // corner radius

	difference() {
	hull() // basic block
	for (i=[-1,1], j=[-1,1])
	translate([i(BasePlate[0]/2 – PlateRound),j(BasePlate[1]/2 – PlateRound),0])
	cylinder(r=PlateRound,h=BasePlate[2],$fn=4*4);

	for (i=[-1:1], j=[-1:1]) // index marks
	translate([i100/2,j100/2,BasePlate[2] – 2*ThreadThick])
	cylinder(d=1.5,h=1,$fn=6);

	for (i=[-1,1], j=[-1,0,1]) // holes for tooling plate studs
	translate([iStudOC[0]ceil(Platter[OD] / StudOC[0])/2,j*StudOC[0],-Protrusion])
	PolyCyl(StudClear,BasePlate[2] + 2*Protrusion,6);

	translate([0,0,-Protrusion]) // center clamp hole
	PolyCyl(StudClear,BasePlate[2] + 2*Protrusion,6);

	translate([0,0,BasePlate[2] – Platter[LENGTH]]) // disk locating recess
	linear_extrude(height=(Platter[LENGTH] + Protrusion),convexity=2)
	difference() {
	circle(d=(Platter[OD] + 1),$fn=8*4);
	circle(d=Platter[ID],$fn=8*4);
	}

	translate([0,0,BasePlate[2] – 4.0]) // drilling recess
	linear_extrude(height=(4.0 + Protrusion),convexity=2)
	difference() {
	circle(d=(Platter[OD] – 10),$fn=8*4);
	circle(d=(Platter[ID] + 10),$fn=8*4);
	}
	}

	}

	//———————-
	// Tube Socket

	module Socket(Name = DefaultSocket) {

	NumSides = 6*4;

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," socket"));
	echo(str(" Punch: ",TubeData[Tube][T_PUNCHOD]," mm = ",TubeData[Tube][T_PUNCHOD]/inch," inch"));
	echo(str(" Screws: ",TubeData[Tube][T_SCREWOC]," mm =",TubeData[Tube][T_SCREWOC]/inch," inch OC"));

	OAH = Pixel[LENGTH] + SocketShim + TubeData[Tube][T_PINLEN];
	BaseHeight = OAH – PanelThick;

	difference() {
	union() {
	linear_extrude(height=BaseHeight) // base outline
	hull() {
	circle(d=(TubeData[Tube][T_PUNCHOD] + 2*SocketFlange),$fn=NumSides);
	for (i=[-1,1])
	translate([i*TubeData[Tube][T_SCREWOC]/2,0])
	circle(d=2.0*SocketNut[OD],$fn=NumSides);
	}
	cylinder(d=TubeData[Tube][T_PUNCHOD],h=OAH,$fn=NumSides); // boss in chassis punch hole
	}

	for (i=[0:(TubeData[Tube][T_NUMPINS] – 1)]) // tube pins
	rotate(i*360/TubeData[Tube][T_NUMPINS])
	translate([TubeData[Tube][T_PINBCD]/2,0,(OAH – TubeData[Tube][T_PINLEN])])
	rotate(180/4)
	PolyCyl(TubeData[Tube][T_PINOD],(TubeData[Tube][T_PINLEN] + Protrusion),4);

	for (i=[-1,1]) // mounting screw holes & nut traps / threaded inserts
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,-Protrusion]) {
	PolyCyl(SocketNut[OD],(SocketNut[LENGTH] + Protrusion),NutSides);
	PolyCyl(SocketNut[ID],(OAH + 2*Protrusion),NutSides);
	}

	translate([0,0,-Protrusion]) { // LED recess
	PolyCyl(Pixel[OD],(Pixel[LENGTH] + Protrusion),8);
	}

	translate([0,0,(Pixel[LENGTH] – Protrusion)]) { // light pipe
	rotate(180/TubeData[Tube][T_NUMPINS])
	PolyCyl(TubeData[Tube][T_PIPEOD],(OAH + 2*Protrusion),TubeData[Tube][T_NUMPINS]);
	}

	for (i=[-1,1]) // cable retaining slots
	translate([i*(Pixel[OD] + TubeData[Tube][T_SCREWOC])/4,0,(Pixel[LENGTH] – Protrusion)/2])
	cube([Pixel[LENGTH],TubeData[Tube][T_SCREWOC],(Pixel[LENGTH] + Protrusion)],center=true);
	}

	// Totally ad-hoc support structures …

	if (Support) {
	color("Yellow") {
	for (i=[-1,1]) // nut traps
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,(SocketNut[LENGTH] – ThreadThick)/2])
	for (a=[0:5])
	rotate(a*30 + 15)
	cube([2ThreadWidth,0.9SocketNut[OD],(SocketNut[LENGTH] – ThreadThick)],center=true);

	if (Pixel[OD] > TubeData[Tube][T_PIPEOD]) // support pipe only if needed
	translate([0,0,(Pixel[LENGTH] – ThreadThick)/2])
	for (a=[0:7])
	rotate(a*22.5)
	cube([2ThreadWidth,0.9Pixel[OD],(Pixel[LENGTH] – ThreadThick)],center=true);
	}
	}
	}


	//———————-
	// Greenlee punch bushings

	module PunchBushing(Name = DefaultSocket) {

	PunchScrew = 9.5;
	BushingThick = 3.0;

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," bushing"));

	NumSides = 6*4;

	difference() {
	union() {
	cylinder(d=Platter[ID],h=BushingThick,$fn=NumSides);
	cylinder(d=TubeData[Tube][T_PUNCHOD],h=(BushingThick – Platter[LENGTH]),$fn=NumSides);
	}
	translate([0,0,-Protrusion])
	PolyCyl(PunchScrew,5.0,8);
	}
	}

	//———————-
	// Tube clamp

	module TubeClamp(Name = DefaultSocket) {

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," clamp"));

	ClampWidth = 37.0; // inside of clamp arch
	ClampLength = 20; // along tube base

	ClampScrew = [6.0,7.8,6.0]; // nose of clamp screw
	ClampArc = 3*45; // angle subtended by block bottom

	ClampChordWidth = 2 * (TubeData[Tube][T_TUBEOD]/2) * sin(ClampArc/2);
	ClampChordDepth = (ClampChordWidth / 2) * tan(ClampArc/4);
	echo(str("Chord width: ",ClampChordWidth," depth: ",ClampChordDepth));

	ClampBlock = [ClampWidth,(ClampChordDepth + 2*ClampScrew[LENGTH]),ClampLength];

	difference() {
	translate([0,(ClampBlock[1]/2 + TubeData[Tube][T_TUBEOD]/2 – ClampChordDepth),0])
	intersection() {
	translate([0,0,ClampLength/2])
	cube(ClampBlock,center=true);
	translate([0,(ClampBlock[1]/2 – ClampWidth/2),0])
	cylinder(d=ClampWidth,h=ClampLength);
	}
	translate([0,0,-Protrusion]) // remove tube base (remains centered)
	cylinder(d=TubeData[Tube][T_TUBEOD],h=(ClampLength + 2*Protrusion));
	translate([0,(TubeData[Tube][T_TUBEOD]/2 + ClampScrew[LENGTH]),ClampBlock[LENGTH]/3])
	rotate([-90,0,0])
	PolyCyl(ClampScrew[ID],2*ClampScrew[LENGTH],6);
	}

	}

	//———————-
	// Build it

	if (Layout == "Cap") {
	if (Section)
	difference() {
	Cap();
	translate([-CapSize[OD],0,CapSize[LENGTH]])
	cube([2CapSize[OD],2CapSize[OD],3*CapSize[LENGTH]],center=true);
	}
	else
	Cap();
	}

	if (Layout == "FinCap") {
	if (Section) render(convexity=5)
	difference() {
	FinCap();
	// translate([0,-FinCapSize[OD],FinCapSize[LENGTH]])
	// cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	translate([-FinCapSize[OD],0,FinCapSize[LENGTH]])
	cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	}
	else
	FinCap();
	}

	if (Layout == "BuildFinCap")
	translate([0,0,FinCapSize[LENGTH]])
	rotate([180,0,0])
	FinCap();

	if (Layout == "LampBase")
	LampBase();

	if (Layout == "PlatterBase")
	PlatterBase();

	if (Layout == "PlatterFixture")
	PlatterFixture();

	if (Layout == "USBPort")
	USBPort();

	if (Layout == "TubeClamp")
	TubeClamp("Octal");

	if (Layout == "Bushings")
	PunchBushing();

	if (Layout == "Socket")
	if (Section) {
	difference() {
	Socket();
	translate([-100/2,0,-Protrusion])
	cube([100,50,50],center=false);
	}
	}
	else
	Socket();

	if (Layout == "Sockets") {
	translate([0,50,0])
	Socket("Mini7");
	translate([0,20,0])
	Socket("Octal");
	translate([0,-15,0])
	Socket("Duodecar");
	translate([0,-50,0])
	Socket("Noval");
	translate([0,-85,0])
	Socket("Magnoval");}

view raw Vacuum Tube Lights.scad hosted with ❤ by GitHub

2016-09-26

Tag: M2

Reticle Guide for Ruler Quilting

Pencil Guides for Ruler Quilting

Makergear M2: Spring-Loaded Extruder Feed Gear

Vacuum Tube LEDs: Improved Sockets

Vacuum Tube LEDs: Milling a 0D3 Spigot the Right Way

Improved Octal Tube Base Clamp

Octal Tube Base Clamp