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.
Mechanical widgetry
Earlier this year, I finally hauled a pile o’ scrap metal to the recycler. For future reference, here’s what clattered down on the scale:
I think the IRONY tag means ferrous bits & pieces in the mix. There’s a powerful motivation to hand them clean copper scrap, although I stop just after cutting off soldered pipe fittings and before stripping insulation.
Memo to Self: Next time, ask about PCBs and gold-plated connectors.
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:
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:
Hey, it’s time for a ride!
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:
Optionally, with rounded ends just for pretty:
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:
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:
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)) – 2*4*ThreadThick, | |
| 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([2*PlateRad,2*PlateRad,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,$fn=2*BallSides); // basic ball | |
| cube([2*BallOD,2*BallOD,BallLength],center=true); // trim to length | |
| } | |
| translate([0,0,-LightBodies[FlashIndex][F_GRIPOD]]) | |
| rotate(180/BallSides) | |
| PolyCyl(LightBodies[FlashIndex][F_GRIPOD],2*BallOD,BallSides); // remove flashlight body | |
| for (i=[0:NumSlots/2 – 1]) { // cut slots | |
| a=i*(2*360/NumSlots); | |
| SlotCutterLength = LightBodies[FlashIndex][F_GRIPOD]; | |
| rotate(a) | |
| translate([SlotCutterLength/2,0,SlotBaseThick]) | |
| cube([SlotCutterLength,SlotWidth,BallLength],center=true); | |
| rotate(a + 360/NumSlots) | |
| translate([SlotCutterLength/2,0,-SlotBaseThick]) | |
| cube([SlotCutterLength,SlotWidth,BallLength],center=true); | |
| } | |
| } | |
| color("Yellow") | |
| if (Support) { | |
| for (i=[0:NumSlots-1]) { | |
| a = i*360/NumSlots; | |
| rotate(a + 180/NumSlots) | |
| translate([(LightBodies[FlashIndex][F_GRIPOD] + RibLength)/2 + ThreadWidth,0,BallLength/(2*4)]) | |
| cube([RibLength,2*ThreadWidth,BallLength/4],center=true); | |
| } | |
| } | |
| } | |
| //- Clamp around flashlight ball | |
| module BallClamp() { | |
| BossLength = ClampScrew[LENGTH] – 1*ClampScrewWasher[LENGTH]; | |
| BossOD = ClampInsert[OD] + 2*(6*ThreadWidth); | |
| difference() { | |
| union() { | |
| intersection() { | |
| sphere(d=ClampOD,$fn=BallSides); // exterior ball clamp | |
| cube([ClampLength,2*ClampOD,2*ClampOD],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([2*ClampOD,2*ClampOD,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([2*ClampOD,2*ClampOD,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(); |
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:
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:
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.
The original ball around the flashlight consisted of two identical parts joined with 2 mm screws and brass inserts:
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:
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.
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:
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:
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([2*BallOD,2*BallOD,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*(2*360/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); | |
| } | |
| } | |
| } |
The mandatory warning stickers leave no doubt as to what’s in the box:
You can imagine my relief when the lithium cells arrived intact:
FWIW, the ATK lithium cells arrived in a small box, snugly tucked into a form-fitting foam block:
As long as nothing happens, it doesn’t matter, right?
You’d think Amazon would have learned something from their day in court, though …
The tiny lip holding the new LED ring light into the microscope snout lacked enough traction and deposited the ring light on the desk. Having picked up a roll of Scotch Extreme Mounting Tape to see how well it works to attach LEDs to vacuum tubes, I’ll see how well it affixes a ring light to a microscope:
The red plastic film separates the tape layers on the spool; the tape itself consists of incredibly sticky, gooey adhesive on a very flexible foam backing. As you can tell from the ragged edges, cutting it requires some effort, with the adhesive instantly gumming up scissors. I applied a razor knife around the microscope snout’s perimeter, pressing from the red film side and pulling the cut sections apart as I went.
The adhesive exposed on the edges of the roll will glue it to anything it touches, so hang up the roll. Laying it on a shelf will definitely cause heartache & confusion.
The instructions on the back label suggest 2 square inches of tape will hold 1 pound:
Given that the ring light weighs a few ounces, tops, those two strips should do fine.
The Smell of Molten Projects in the Morning 