Tag: Improvements

Making the world a better place, one piece at a time

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

Maloney Road Repaving

The Wappinger DPW laid asphalt along Maloney Rd, from side to side and end to end (well, to the end of their jurisdiction at the Lagrange town boundary). We passed the crew putting down the first layer on the westbound side:

Maloney Road Paving – 2016-09-14

A few days later, they were doing the final layer on that side as we approached the Rail Trail entrance:

Maloney Road Paving – 2016-09-17

Sometimes, good things happen out there on the roads!

[Update: Vedran points to a Youtube video of paving:

Paving Operations

By the looks of it they are from (almost) your neck of the woods (NYCDOT). They have a mighty impressive machine going but if you watch the lower right corner for about 10 seconds you’ll spot them paving right over a manhole cover :) Guess no matter how smart the tech, users will always find a way.

I’ve seen that done, too, but a guy should immediately dig out the cover (using the paint marks on the curb to find it) and taper the edges. That way, the paving machine produces a smooth surface along the street and the cover isn’t (shouldn’t be!) too deeply recessed.

Sometimes they just spraypaint a circle over the buried cover and wait until somebody must go into that hole before digging it out. That makes a nice, smooth paving job, but eventually produces a steep-walled pit in the pavement which enlarges and crumbles into gravel.

They should add a ring to the manhole to bring the cover flush with the new surface, but nobody (except the WDPW above!) does that around here until after the third or fourth paving job. Until then, it’s just like a pothole with a slick metallic bottom …

/update]

2016-10-02

Bulk-renaming Video Snapshots

For reasons that should be obvious by now, I review the helmet camera video from (some of) our bike rides and extract snapshots of interesting events. VLC auto-names the snapshots along these lines:

-rw-rw-r-- 1 ed ed  4.0M 2016-09-16 16:15 vlcsnap-2016-09-16-16h15m43s49.png
-rw-rw-r-- 1 ed ed  3.2M 2016-09-16 16:15 vlcsnap-2016-09-16-16h15m59s181.png
-rw-rw-r-- 1 ed ed  2.7M 2016-09-16 16:18 vlcsnap-2016-09-16-16h18m58s125.png
-rw-rw-r-- 1 ed ed  3.7M 2016-09-16 18:40 vlcsnap-2016-09-16-18h40m22s7.png
-rw-rw-r-- 1 ed ed  3.5M 2016-09-16 18:40 vlcsnap-2016-09-16-18h40m58s132.png
-rw-rw-r-- 1 ed ed  3.5M 2016-09-16 18:41 vlcsnap-2016-09-16-18h41m29s181.png
-rw-rw-r-- 1 ed ed  3.9M 2016-09-16 18:41 vlcsnap-2016-09-16-18h41m42s60.png
-rw-rw-r-- 1 ed ed  3.8M 2016-09-16 18:41 vlcsnap-2016-09-16-18h41m54s146.png
-rw-rw-r-- 1 ed ed  3.8M 2016-09-16 18:42 vlcsnap-2016-09-16-18h42m22s206.png
-rw-rw-r-- 1 ed ed  3.7M 2016-09-16 18:42 vlcsnap-2016-09-16-18h42m38s58.png

The gap in the timestamp after the first three files reveals a random errand.

First, convert to JPG format, place the results in another directory and, en passant, mash them to a reasonable size:

mkdir /some-useful-directory/Road\ Repair/"Rt 82 and CR 29"
for f in  vlcsnap-2016-09-16* ; do convert $f -density 300 -define jpeg:extent=200KB /some-useful-directory/Road\ Repair/"Rt 82 and CR 29"/${f%%.*}.jpg ; done
cd /some-useful-directory/Road\ Repair/"Rt 82 and CR 29"

Replace the first part of the VLC-generated names with relevant identification:

rename 's/vlcsnap-/Rt 82 - /' vlcsnap-2016-09-16-16*
rename 's/vlcsnap-/CR 29 - /' vlcsnap*

The directory now contains these files:

-rw-rw-r-- 1 ed ed 193K 2016-09-19 11:36 CR 29 - 2016-09-16-18h40m22s7.jpg
-rw-rw-r-- 1 ed ed 192K 2016-09-19 11:36 CR 29 - 2016-09-16-18h40m58s132.jpg
-rw-rw-r-- 1 ed ed 193K 2016-09-19 11:36 CR 29 - 2016-09-16-18h41m29s181.jpg
-rw-rw-r-- 1 ed ed 193K 2016-09-19 11:36 CR 29 - 2016-09-16-18h41m42s60.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 11:36 CR 29 - 2016-09-16-18h41m54s146.jpg
-rw-rw-r-- 1 ed ed 196K 2016-09-19 11:36 CR 29 - 2016-09-16-18h42m22s206.jpg
-rw-rw-r-- 1 ed ed 196K 2016-09-19 11:36 CR 29 - 2016-09-16-18h42m38s58.jpg
-rw-rw-r-- 1 ed ed 195K 2016-09-19 11:36 Rt 82 - 2016-09-16-16h15m43s49.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 11:36 Rt 82 - 2016-09-16-16h15m59s181.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 11:36 Rt 82 - 2016-09-16-16h18m58s125.jpg

These bursts of Perl regex line noise replace the snapshot timestamp on those files with an ascending sequence number, with separate sequences for each group:

i=1 ; for f in CR* ; do rename -v "s/-1[68]h..m..s\d{1,3}/ - $(( i++ ))/" "$f" ; done
i=1 ; for f in Rt* ; do rename -v "s/-1[68]h..m..s\d{1,3}/ - $(( i++ ))/" "$f" ; done

And then the files make sense:

-rw-rw-r-- 1 ed ed 193K 2016-09-19 13:51 CR 29 - 2016-09-16 - 1.jpg
-rw-rw-r-- 1 ed ed 192K 2016-09-19 13:51 CR 29 - 2016-09-16 - 2.jpg
-rw-rw-r-- 1 ed ed 193K 2016-09-19 13:51 CR 29 - 2016-09-16 - 3.jpg
-rw-rw-r-- 1 ed ed 193K 2016-09-19 13:51 CR 29 - 2016-09-16 - 4.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 13:51 CR 29 - 2016-09-16 - 5.jpg
-rw-rw-r-- 1 ed ed 196K 2016-09-19 13:51 CR 29 - 2016-09-16 - 6.jpg
-rw-rw-r-- 1 ed ed 196K 2016-09-19 13:51 CR 29 - 2016-09-16 - 7.jpg
-rw-rw-r-- 1 ed ed 195K 2016-09-19 13:51 Rt 82 - 2016-09-16 - 1.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 13:51 Rt 82 - 2016-09-16 - 2.jpg
-rw-rw-r-- 1 ed ed 194K 2016-09-19 13:51 Rt 82 - 2016-09-16 - 3.jpg

The hard part, this time around, involved figuring a regex for the timestamp. The trick was to specify a single digit for the milliseconds part, with a repetition count allowing for one-to-three digits.

The Perl regex cheat sheet helped.

The double quotes around the rename search parameter allows the shell to expand the $(( i++ )) gibberish. The double quotes around the file name keep the blank-separated parts together.

At some point I must figure out how to produce leading-zero-filled sequence numbers, which will probably involve a printf.

The ride covered some roads with “2 to 4 foot” shoulders, which seems overly optimistic:

Rt 82 - 2016-09-16 - 3 — Rt 82 – 2016-09-16 – 3

NYSDOT and DCDPW both believe a homeopathic strip of asphalt will cover faults in the travel lane and don’t care that the right side of the strip puts an abrupt ledge along the middle of the minimal and fissured shoulder:

Rt 82 - 2016-09-16 - 1 — Rt 82 – 2016-09-16 – 1

Ah, well, it was a lovely day for a ride …

2016-09-30

Vacuum Tube LEDs: Fully Dressed 21HB5A

Black PETG definitely looks better than cyan for this job:

21HB5A – Black PETG base – flash

Holding the plate cap to the tube with a thin ring of opaque epoxy cuts down on the glare under its edge:

21HB5A – Black PETG base – cyan phase

Fire in the bottle!

21HB5A – Black PETG fittings – punched drive platter – purple phase

It’s still running basically the same Arduino code as before, but I have some ideas about that…

2016-09-20
Hard Drive Platter Punch Bushing

The last time I punched a hard drive platter, I lathe-turned a bushing to center the Greenlee punch:

Greenlee punched drive platter

This will work better:

Vacuum Tube Lights – Greenlee punch bushing

The OD centers the bushing inside the punch body, the ID captures the screw, and the raised boss captures the platter.

After drilling the platter on the new fixture, it’s ready for punching:

Hard drive platter – Greenlee punch bushing

Line everything up, turn the screw, and It Just Works:

Hard drive platter – punched

The masking tape holds the platter to the bushing, eliminating the need for a third hand. The bushing emerges unscathed, ready for another platter. Overall, I think that’s faster and less messy than milling the platter ID on the Sherline.

Printing out a base to fit the Duodecar socket and assembling all the parts:

21HB5A in socket on platter – detail

The Duodecar pin circle (19.1 BCD + 1.05 pin diameter) will actually fit inside a hard drive platter’s 25 mm unpunched ID. It might look a bit squinched, but the less you see of the socket, the better. I’ll try that on the next one.

The OpenSCAD source code is the same as before; set Layout = Bushings; and a bushing will pop out.

The original bushing doodle with dimensions:

Greenlee 1.25 inch punch bushing for hard drive platter – dimension doodle

2016-09-19
Vacuum Tube LEDs: Aligning the Plate Cap Leads

The original plate cap, even without fins, seemed entirely too large for the 21HB5A tube. There’s not much wasted space inside and, after trimming the outside a bit, this is about as small as seems possible:

Vacuum Tube Lights – thin cap solid model – section

PETG doesn’t bridge well and, after cleaning out the wire hole, the remaining shell didn’t hold the brass tube very securely. Epoxying tubes into two caps at once, with a longer brass tube holding them in alignment, worked well:

Black PETG Plate Caps – brass tube alignment

The tube eliminates vertical tilt and you (well, I) can eyeballometrically align the caps and tubes in azimuth. The thin ring of JB Kwik epoxy around the brass tube isn’t visible, so it’s all good:

21HB5A – Black PETG base – flash

This project may eventually force me to try epoxy coating, high-build primer, and good paint…

2016-09-16
Hard Drive Platter Drilling Fixture

After drilling the platter for a Noval tube, I finally made a fixture to hold the platters firmly, but gently, in the proper position for drilling:

Hard drive platter – drilling fixture

The platter sits more-or-less flush with the surface, where credit-card plastic pads work fine. Thinner platters may require compliant padding.

The solid model has locating pips at ±50 mm from the center and airspace below the platter for the drill bit:

Vacuum Tube Lights – hard drive fixture – solid model

The 1.16 inch hole spacing matches the Sherline’s tooling plate. The center hole seemed like a Good Idea, although it has no purpose right now.

The OpenSCAD source code is the same as before; just set Layout = PlatterFixture; and it’ll produce the right thing.

2016-09-14