The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Category: Recumbent Bicycling

Cruisin’ the streets

Sandisk Extreme Pro MicroSD Card: End of Life?

The Sandisk Extreme Pro 64 GB MicroSD card in the Sony HDR-AS30V died on the road once more, got reformatted, worked OK for a while, then kicked out catastrophic I/O errors after being mounted, so I swapped in the High Endurance card:

Sandisk – 64 GB MicroSDXC cards

The Extreme Pro still passes the f3probe tests, so it’s not completely dead, but if I can’t trust it in the helmet camera, it’s dead to me.

It survived 17 months of more-or-less continuous use, although we didn’t do nearly enough riding for three months early this year. Call it 14 months x five rides / week x 1 hour / ride = 300 hours of recording. Multiply by 4 GB / 22.75 minutes to get 3 TB of video, about 50 times its total capacity.

The never-sufficiently-to-be-damned Sony cards failed after less than 1 TB and 15-ish times capacity, making the Sandisk Extreme Pro much better. However, it’s painfully obvious these cards work better for low-intensity still-image recording, rather than continuous HD video.

Using them as Raspberry Pi “hard drives” surely falls somewhere between still cameras and video, although Octoprint’s video snapshots and streaming media must make ’em sweat.

We’ll see how Sandisk’s High Endurance memory works in precisely the application it’s labeled for.

2017-08-22
Tenergy 18650 Lithium Cells: Initial Capacity

The daytime running lights on the bikes get noticeably dimmer when the 18650 lithium cell voltage drops below 3.6 V, so I picked up a quartet of Tenergy protected cells and ran ’em through the battery tester:

Tenergy 18650 Protected – 2017-08-04

As with the ATX cells, the voltage decreases almost linearly with charge until it falls off the cliff near the end, but these have a higher terminal voltage throughout most of the curve, which is a Good Thing for LED flashlights.

These four seem to have about the same overall capacity as the ATX cells, so we’ll run ’em all in sequence and see how long they last.

2017-08-21
Tour Easy Daytime Running Light: Pile of Prototypes

Although I wish I could come up with a finished design in one pass, usually I end up with a big pile of nope before producing the one I want:

Fairing Flashlight Mount – Iterations

The mounts on the left show the progression from large hemisphere balls to the same-size finger ball to the smaller finger ball, with the smaller cyan arch clamp in the foreground still festooned with its support structure. The stack of plates to the right (with the original faded & distintegrating ABS plates in the bag) comes from reprinting in cyan to match the small mounts now on the bikes:

Fairing Flashlight Mount – rounded

Hey, it’s time for a ride!

2017-08-18

Tour Easy Daytime Running Light: Annotation

The flashlight mount need not be symmetric after applying all the rotations, so recording how it’s aimed and which end goes forward seemed appropriate:

Fairing Flashlight Mount - Mount Annotation — Fairing Flashlight Mount – Mount Annotation

Optionally, with rounded ends just for pretty:

Fairing Flashlight Mount - Mount Annotation - rounded — Fairing Flashlight Mount – Mount Annotation – rounded

Because the rounding comes from resized spheres, the plate gets a ridge along the top to (maybe) lock the nylon screws / wing nuts in place:

Fairing Flashlight Mount - Mount - rounded — Fairing Flashlight Mount – Mount – rounded

Or discourage them from turning, which would be OK, too. After the second tightening, they don’t seem to come loose, so this may be overthinking the problem.

All in all, they look pretty good in cyan PETG:

Fairing Flashlight Mount - rounded — Fairing Flashlight Mount – rounded

Believe it or not, that’s aimed so the top edge of the beam is roughly horizontal to keep the hot spot out of oncoming traffic. They’re plenty bright, even on the “low power” setting.

The flashlight mounting balls produce a decorative brim that ought to be useful for something:

Maybe earrings?

The OpenSCAD source code as a GitHub Gist:

	// Tour Easy Fairing Flashlight Mount
	// Ed Nisley KE4ZNU – July 2017
	// August 2017 –

	/* [Build Options] */

	FlashName = "AnkerLC40"; // [AnkerLC40,AnkerLC90,J5TactV2,InnovaX5]

	Component = "Plates"; // [Ball, BallClamp, Mount, Plates, Bracket]

	Layout = "Build"; // [Build, Show]

	Support = false;

	MountSupport = true;

	/* [Extrusion] */

	ThreadThick = 0.25; // [0.20, 0.25]
	ThreadWidth = 0.40; // [0.40]

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

	Protrusion = 0.01; // [0.01, 0.1]

	HoleWindage = 0.2;

	/* [Fairing Mount] */

	ToeIn = 0; // inward from ahead
	Tilt = 20; // upward from forward (M=20 E=15)
	Roll = 0; // outward from top

	Shift = 0; // Finagle Constant for support ribs

	//- Screws *c

	/* [Hidden] */

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

	/* [Screws and Inserts] */

	ClampInsert = [3.0,4.2,8.0];

	ClampScrew = [3.0,5.9,35.0]; // thread dia, head OD, screw length
	ClampScrewWasher = [3.0,6.75,0.5];
	ClampScrewNut = [3.0,6.1,4.0]; // nyloc nut

	/* [Hidden] */

	F_NAME = 0;
	F_GRIPOD = 1;
	F_GRIPLEN = 2;

	LightBodies = [
	["AnkerLC90",26.6,48.0],
	["AnkerLC40",26.6,55.0],
	["J5TactV2",25.0,30.0],
	["InnovaX5",22.0,55.0]
	];

	//- Fairing Bracket
	// Magic numbers taken from the actual fairing mount

	/* [Hidden] */

	inch = 25.4;

	BracketHoleOD = 0.25 * inch; // 1/4-20 bolt holes

	BracketHoleOC = 1.0 * inch; // fairing hole spacing
	// usually 1 inch, but 15/16 on one fairing

	Bracket = [48.0,16.3,3.6 – 0.6]; // fairing bracket end plate overall size
	BracketHoleOffset = (3/8) * inch; // end to hole center

	BracketM = 3.0; // endcap arc height
	BracketR = (pow(BracketM,2) + pow(Bracket[1],2)/4) / (2*BracketM); // … radius

	//- Base plate dimensions

	Plate = [100.0,30.0,6*ThreadThick + Bracket[2]];
	PlateRad = Plate[1]/4;

	RoundEnds = true;

	echo(str("Base plate thick: ",Plate[2]));

	//- Select flashlight data from table

	echo(str("Flashlight: ",FlashName));
	FlashIndex = search([FlashName],LightBodies,1,0)[F_NAME];

	//- Set ball dimensions

	BallWall = 5.0; // max ball wall thickness
	echo(str("Ball wall: ",BallWall));

	BallOD = IntegerMultiple(LightBodies[FlashIndex][F_GRIPOD] + 2*BallWall,1.0);
	echo(str(" OD: ",BallOD));

	BallLength = IntegerMultiple(min(sqrt(pow(BallOD,2) – pow(LightBodies[FlashIndex][F_GRIPOD],2)) – 24ThreadThick,
	LightBodies[FlashIndex][F_GRIPLEN]),1.0);
	echo(str(" length: ",BallLength));

	BallSides = 8*4;

	//- Set clamp ring dimensions

	ClampOD = 50;
	echo(str("Clamp OD: ",ClampOD));

	ClampLength = min(20.0,0.75*BallLength);
	echo(str(" length: ",ClampLength));

	ClampScrewOC = IntegerMultiple((ClampOD + BallOD)/2,1);
	echo(str(" screw OC: ",ClampScrewOC));

	//- Adjust hole diameter to make the size come out right

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

	//- Fairing Bracket
	// This part of the fairing mount supports the whole flashlight mount
	// Centered on screw hole

	module Bracket() {

	linear_extrude(height=Bracket[2],convexity=2)
	difference() {
	translate([(Bracket[0]/2 – BracketHoleOffset),0,0])
	offset(delta=ThreadWidth)
	intersection() {
	square([Bracket[0],Bracket[1]],center=true);
	union() {
	for (i=[-1,0,1]) // middle circle fills gap
	translate([i*(Bracket[0]/2 – BracketR),0])
	circle(r=BracketR);
	}
	}
	circle(d=BracketHoleOD/cos(180/8),$fn=8); // dead center at the origin
	}
	}

	//- General plate shape
	// Centered on the hole for the fairing bracket

	module PlateBlank() {

	difference() {
	translate([BracketHoleOC,0,0])
	intersection() {
	translate([0,0,Plate[2]/2]) // select upper half of spheres
	cube(Plate,center=true);
	hull()
	if (RoundEnds)
	for (i=[-1,1])
	translate([i*(Plate[0]/2 – PlateRad),0,0])
	resize([Plate[1]/2,Plate[1],2*Plate[2]])
	sphere(r=PlateRad); // nice round ends!
	else
	for (i=[-1,1], j=[-1,1])
	translate([i(Plate[0]/2 – PlateRad),j(Plate[1]/2 – PlateRad),0])
	resize([2PlateRad,2PlateRad,2*Plate[2]])
	sphere(r=PlateRad); // nice round corners!
	}
	translate([2*BracketHoleOC,0,-Protrusion]) // punch screw holes
	PolyCyl(BracketHoleOD,2*Plate[2],8);
	translate([0,0,-Protrusion])
	PolyCyl(BracketHoleOD,2*Plate[2],8);
	}
	}

	//- Inner plate

	module InnerPlate() {

	difference() {
	PlateBlank();
	translate([0,0,Plate[2] – Bracket[2] + Protrusion]) // punch fairing bracket
	Bracket();
	}
	}

	//- Slotted ball around flashlight
	// Print with brim to ensure adhesion!

	module SlotBall() {

	NumSlots = 8*2; // must be even, half cut from each end
	SlotWidth = 2*ThreadWidth;
	SlotBaseThick = 10*ThreadThick; // enough to hold finger ends together
	RibLength = (BallOD – LightBodies[FlashIndex][F_GRIPOD])/2;

	translate([0,0,BallLength/2])
	difference() {
	intersection() {
	sphere(d=BallOD,$fn=2*BallSides); // basic ball
	cube([2BallOD,2BallOD,BallLength],center=true); // trim to length
	}
	translate([0,0,-LightBodies[FlashIndex][F_GRIPOD]])
	rotate(180/BallSides)
	PolyCyl(LightBodies[FlashIndex][F_GRIPOD],2*BallOD,BallSides); // remove flashlight body

	for (i=[0:NumSlots/2 – 1]) { // cut slots
	a=i(2360/NumSlots);
	SlotCutterLength = LightBodies[FlashIndex][F_GRIPOD];
	rotate(a)
	translate([SlotCutterLength/2,0,SlotBaseThick])
	cube([SlotCutterLength,SlotWidth,BallLength],center=true);
	rotate(a + 360/NumSlots)
	translate([SlotCutterLength/2,0,-SlotBaseThick])
	cube([SlotCutterLength,SlotWidth,BallLength],center=true);
	}
	}

	color("Yellow")
	if (Support) {
	for (i=[0:NumSlots-1]) {
	a = i*360/NumSlots;
	rotate(a + 180/NumSlots)
	translate([(LightBodies[FlashIndex][F_GRIPOD] + RibLength)/2 + ThreadWidth,0,BallLength/(2*4)])
	cube([RibLength,2*ThreadWidth,BallLength/4],center=true);
	}
	}
	}

	//- Clamp around flashlight ball

	module BallClamp() {

	BossLength = ClampScrew[LENGTH] – 1*ClampScrewWasher[LENGTH];
	BossOD = ClampInsert[OD] + 2(6ThreadWidth);

	difference() {
	union() {
	intersection() {
	sphere(d=ClampOD,$fn=BallSides); // exterior ball clamp
	cube([ClampLength,2ClampOD,2ClampOD],center=true); // aiming allowance
	}
	hull()
	for (j=[-1,1])
	translate([0,j*ClampScrewOC/2,-BossLength/2])
	cylinder(d=BossOD,h=BossLength,$fn=6);
	}

	sphere(d=(BallOD + 1*ThreadThick),$fn=BallSides); // interior ball with minimal clearance

	for (j=[-1,1]) {
	translate([0,j*ClampScrewOC/2,-ClampOD]) // screw clearance
	PolyCyl(ClampScrew[ID],2*ClampOD,6);
	translate([0,j*ClampScrewOC/2, // insert clearance
	-(BossLength/2 – ClampInsert[LENGTH] – 3*ThreadThick)])
	rotate([0,180,0])
	PolyCyl(ClampInsert[OD],2*ClampOD,6);
	translate([0,j*ClampScrewOC/2, // insert transition
	-(BossLength/2 – ClampInsert[LENGTH] – 3*ThreadThick)])
	cylinder(d1=ClampInsert[OD]/cos(180/6),d2=ClampScrew[ID],h=6*ThreadThick,$fn=6);
	}
	}

	color("Yellow")
	if (Support) { // ad-hoc supports for top half
	NumRibs = 6;
	RibLength = 0.5 * BallOD;
	RibWidth = 1.9*ThreadWidth;
	SupportOC = ClampLength / NumRibs;

	cube([ClampLength,RibLength,4*ThreadThick],center=true); // base plate for adhesion

	render(convexity=2*NumRibs)
	intersection() {
	sphere(d=BallOD – 0*ThreadWidth); // cut at inner sphere OD
	cube([ClampLength + 2*ThreadWidth,RibLength,BallOD],center=true);
	union() { // ribs for E-Z build
	for (j=[-1,0,1])
	translate([0,j*SupportOC,0])
	cube([ClampLength,RibWidth,1.0*BallOD],center=true);
	for (i=[0:NumRibs]) // allow NumRibs + 1 to fill the far end
	translate([i*SupportOC – ClampLength/2,0,0])
	rotate([0,90,0])
	cylinder(d=BallOD – 2*ThreadThick,
	h=RibWidth,$fn=BallSides,center=true);
	}
	}
	}
	}

	//- Mount between fairing plate and flashlight ball
	// Build with support for bottom of clamp screws!

	module Mount() {


	difference() {
	translate([-BracketHoleOC,0,0]) // put bracket center at origin
	PlateBlank();
	mirror([0,1,0])
	translate([0,0,-Protrusion])
	linear_extrude(height=3*ThreadThick + Protrusion) {
	translate([BracketHoleOC + 15,0,0])
	text(text=">>>",size=5,spacing=1.20,font="Arial",halign="center",valign="center");
	translate([-BracketHoleOC,8,0])
	text(text=str("Toe ",ToeIn),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
	translate([-BracketHoleOC,-8,0])
	text(text=str("Tilt ",Tilt),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
	translate([BracketHoleOC,8,0])
	text(text=str("Roll ",Roll),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
	translate([-(BracketHoleOC + 15),0,0])
	rotate(90)
	text(text="KE4ZNU",size=4,spacing=1.20,font="Arial",halign="center",valign="center");
	}
	}

	rotate([0,ToeIn,Tilt])
	translate([0,0,ClampOD/2])
	rotate([-Roll,0,0])
	intersection() {
	translate([0,0,-ClampOD/2])
	cube([2ClampOD,2ClampOD,ClampOD],center=true);
	BallClamp();
	}

	color("Yellow")
	if (MountSupport) { // anchor outer corners at worst overhang
	RibWidth = 1.9*ThreadWidth;
	SupportOC = 0.1 * ClampLength;
	difference() {
	rotate([0,0,Tilt])
	translate([Shift,0,0])
	for (i=[-4.5,-2.5,0,2.0,4.5])
	translate([i*SupportOC – 0.0,0,(5 + Plate[2])/2])
	cube([RibWidth,0.7*ClampOD,(5 + Plate[2])],center=true);
	rotate([0,ToeIn,Tilt])
	translate([Shift,0,ClampOD/2])
	rotate([-Roll,0,0])
	sphere(d=ClampOD – 2*ThreadWidth,$fn=BallSides);
	}
	}
	}

	//- Build things

	if (Component == "Ball")
	SlotBall();

	if (Component == "BallClamp")
	if (Layout == "Show")
	BallClamp();
	else if (Layout == "Build") {
	Both = false;
	difference() {
	union() {
	translate([Both ? ClampLength : 0,0,0])
	BallClamp();
	if (Both)
	translate([-ClampLength,0,0])
	rotate([180,0,0])
	BallClamp();
	}
	translate([0,0,-ClampOD/2])
	cube([2ClampOD,2ClampOD,ClampOD],center=true);
	}
	}

	if (Component == "Mount")
	Mount();

	if (Component == "Plates") {
	translate([0,0.7*Plate[1],0])
	InnerPlate();
	translate([0,-0.7*Plate[1],0])
	PlateBlank();
	}

	if (Component == "Bracket")
	Bracket();

view raw Fairing Flashlight Mount.scad hosted with ❤ by GitHub

2017-08-17

J5 V2 Flashlight: Switch Tightening

From the start, the (second) J5 V2 flashlight had an erratic switch that flickered the LED at the slightest pressure. Not enough to switch modes, as it does with a half press, but enough to show something’s not quite right inside.

Taking it apart requires a pin wrench, which I have, but the deeply recessed ring required more reach than any of the tips I’ve made over the years. Introducing a pair of stainless steel 10-32 screws to Mr Grinder added two more pins to the collection:

J5V2 Flashlight – custom pin wrench

The lock ring in the flashlight cap turned out to be finger-loose, certainly contributing to the problem. Removing the lock ring, peeling the rubber dome out of the cap, and poking with a punch sufficed to drive out the guts of the switch assembly:

J5V2 Flashlight – switch parts

Which consists of, as you’d expect, the cheapest possible parts that don’t immediately fail.

The (steel) tab sticking out of the actual switch (in the upper right) contacts the inside of the (aluminum) cap. I bent it slightly outward, added a trace of DeoxIT Red, reassembled everything in reverse order, and it’s all good for the first time in its brief life.

I’d rate J5’s QC as Below Average, given that the first light arrived with built-in dirt and its replacement (this one) had an alien egg next to the LED, plus this loose switch lock ring + crappy tab contact.

The J5 V2 light claims 750 lumen output, but the spot is nowhere near twice as bright as the LC40 lights on the bikes and much dimmer than the LC90 light (which is too big for the bikes), all tweaked for equivalent-size illuminated areas. Given that lumens measure total output and candela measure lumen/steradian, there’s some wiggle room for misinterpretation.

Won’t buy another, for sure.

2017-08-14

Tour Easy Daytime Running Light: Improved Ball Mount

The original ball around the flashlight consisted of two identical parts joined with 2 mm screws and brass inserts:

Flashlight Ball Mount - flattening fins — Flashlight Ball Mount – flattening fins

Providing enough space for the inserts made the ball bigger than it really ought be, so I designed a one-piece ball with “expansion joints” between the fingers:

Fairing Flashlight Mount - Finger Ball - solid model — Fairing Flashlight Mount – Finger Ball – solid model

Having Slic3r put a 3 mm brim around the bottom almost worked. Adding a little support flange, then building with a brim, kept each segment upright and the whole affair firmly anchored.

Fairing Flashlight Mount - Finger Ball - solid model - support fins — Fairing Flashlight Mount – Finger Ball – solid model – support fins

Those had to be part of the model, because I also wanted to anchor the perimeter threads to prevent upward warping. Worked great and cleanup was surprisingly easy: apply the flush cutter, introduce the ball to Mr Belt Sander, then rotate the ball around the flashlight wrapped with fine sandpaper to wear off the nubs.

The joints between the fingers provide enough flexibility to expand slightly around the flashlight body:

Flashlight Mount - finger ball — Flashlight Mount – finger ball

I made that one the same size as the original screw + insert balls to fit the original clamp, where it worked fine. The clamp ring applies enough pressure to the ball to secure the flashlight and prevent the ball from rotating unless you (well, I) apply more-than-incidental force.

Then I shrank the ball to the flashlight diameter + 10 mm (= 5 mm thick at the equator) and reduced the size of the clamp ring accordingly, which made the whole mount much more compact:

Flashlight Mount - LC40 - finger ball - side — Flashlight Mount – LC40 – finger ball – side

Here’s what the larger mount looks like in action:

The flashlights allegedly puts out 400 lumen in a fairly tight beam. The fairings produce a much larger and brighter glint in full sunlight than the flashlights, so I think they’re about the right brightness.

The OpenSCAD source code for the new ball as a GitHub Gist:

	//- Slotted ball around flashlight
	// Print with brim to ensure adhesion!

	module SlotBall() {

	NumSlots = 8*2; // must be even, half cut from each end
	SlotWidth = 2*ThreadWidth;
	SlotBaseThick = 10*ThreadThick; // enough to hold finger ends together
	RibLength = (BallOD – LightBodies[FlashIndex][F_GRIPOD])/2;

	translate([0,0,BallLength/2])
	difference() {
	intersection() {
	sphere(d=BallOD,$fn=2*BallSides); // basic ball
	cube([2BallOD,2BallOD,BallLength],center=true); // trim to length
	}
	translate([0,0,-LightBodies[FlashIndex][F_GRIPOD]])
	rotate(180/BallSides)
	PolyCyl(LightBodies[FlashIndex][F_GRIPOD],2*BallOD,BallSides); // remove flashlight body

	for (i=[0:NumSlots/2 – 1]) { // cut slots
	a=i(2360/NumSlots);
	SlotCutterLength = LightBodies[FlashIndex][F_GRIPOD];
	rotate(a)
	translate([SlotCutterLength/2,0,SlotBaseThick])
	cube([SlotCutterLength,SlotWidth,BallLength],center=true);
	rotate(a + 360/NumSlots)
	translate([SlotCutterLength/2,0,-SlotBaseThick])
	cube([SlotCutterLength,SlotWidth,BallLength],center=true);
	}
	}

	color("Yellow")
	if (Support) {
	for (i=[0:NumSlots-1]) {
	a = i*360/NumSlots;
	rotate(a + 180/NumSlots)
	translate([(LightBodies[FlashIndex][F_GRIPOD] + RibLength)/2 + ThreadWidth,0,BallLength/(2*4)])
	cube([RibLength,2*ThreadWidth,BallLength/4],center=true);
	}
	}
	}

view raw Fairing Flashlight Mount.scad – Slotted Ball Excerpt hosted with ❤ by GitHub

2017-08-11

Byonics TinyTrak3+ vs. RFI

Some weeks ago, the APRS + voice adapter on my radio began randomly resetting during our rides, sending out three successive data bursts: the TinyTrak power-on message, an ID string, and the current coordinates. Mary could hear all three packets quite clearly, which was not to be tolerated.

I swapped radios + adapters so that she could ride in peace while I diagnosed the problem, which, of course, was both intermittent and generally occurred only while on the road. The TinyTrak doc mentions “… a sign of the TinyTrak3 resetting due to too much local RF energy”, so I clamped ferrite cores around All! The! Cables! and the problem Went Away.

Removing one core each week eventually left the last core on the GPS receiver’s serial cable, which makes sense, as it plugs directly into the TT3. The core had an ID large enough for several turns (no fool, I), another week established a minimum of three turns kept the RFI down, so I settled for five:

KG-UV3D APRS – ferrite on TT3 GPS cable

Prior to the RFI problem cropping up, nothing changed. Past experience has shown when I make such an assertion, it means I don’t yet know what changed. Something certainly has and not for the better.

I swapped the radios + adapters and all seems quiet.

2017-07-26

Category: Recumbent Bicycling

Sandisk Extreme Pro MicroSD Card: End of Life?

Tenergy 18650 Lithium Cells: Initial Capacity

Tour Easy Daytime Running Light: Pile of Prototypes

Tour Easy Daytime Running Light: Annotation

J5 V2 Flashlight: Switch Tightening

Tour Easy Daytime Running Light: Improved Ball Mount

Byonics TinyTrak3+ vs. RFI