Laser Cutter – Page 15 – The Smell of Molten Projects in the Morning

Windows 11 for the Linux Guy: Hardware

Contrary to what I thought a while ago, the least awful way to continue running LightBurn after Linux support goes away is to stand up a dedicated Windows 11 box:

BeeLink Win 11 PC - overview — BeeLink Win 11 PC – overview

Lest it become lost in the clutter:

BeeLink Win 11 PC - detail — BeeLink Win 11 PC – detail

It’s a BeeLink Mini S12 (whatever that means) and squats near the low end of PC performance these days. I chose it based on reports from folks at Squidwrench having used similar units for various purposes without much pain, plus motivation from one of those weird Amazon “coupons” knocking the price down; it now sells for about that same price without the coupon.

It’s advertised as coming with Windows 11, but my advisors recommended a clean installation to get rid of crapware and possible pre-installed malware. I decided to start with the as-delivered system, then use the same product key to blow away the default installation.

The box / packaging did not include a Microsoft Windows Product Key and going through the first boot setup process produced this disconcerting result:

Win 11 license key - not found — Win 11 license key – not found

More disconcerting: Windows Defender (Microsoft’s antivirus scanner / system integrity checker) was inactive and could not be installed from the MS “Store”. While not conclusive proof of pre-installed malware, the situation certainly seemed suspicious.

The seller sent a key that seemed to be for Windows 10:

BeeLink MS Product Key - Win 10 - redacted — BeeLink MS Product Key – Win 10 – redacted

Having been assured this would also validate a Win 11 installation, I did a clean installation using a USB flash drive produced by the MS installer, was never asked for a key, and eventually got to this point:

Win 11 Pro Installed Key - requires Digital License - redacted — Win 11 Pro Installed Key – requires Digital License – redacted

Despite the missing OEM key and the footnote, everything seems just ducky:

I assume a clean installation blows away any malware resident on the “hard drive” (an M.2 solid state drive, of course), including rootkits and boot sector malware. My threat model does not include malware in the BIOS / UEFI firmware, which may be overoptimistic.

I declined all the optional MS products, refused various MS subscriptions, and generally tried to kill off a myriad invasive / advertising / “customized for you” features along the way. A casual search will produce many helpful guides for that process; I expect the details will change as MS continues to extract information from us. I set up a non-Administrator account for myself specifically to run LightBurn.

With that accomplished, I gave it a static IP address, created network shares to various directories on the “file server” (an ancient off-lease Dell Optiplex) holding the files I previously used with Linux LightBurn, installed Window LightBurn, got its preferences sorted out / restored from backup, and things eventually worked pretty much as intended.

Not shown in the picture:

A trackball set up for my left hand
A 75% keyboard
The USB camera in the laser’s lid for LightBurn’s use.

This setup is intended for layout tweaking and laser control, not for protracted design work while standing in what’s now a 57 °F = 14 °C basement.

For what it’s worth, I must run the laser’s water chiller for half an hour to raise the cooling water to the normal 20 °C operating range; it has a water-cooled pump serving as a little heater.

The next step involved enabling Remote Desktop Protocol access so I can access the Windows box from my Comfy Chair at my usual battle station upstairs. More on that tomorrow …

2024-12-09

Handi-Quilter HQ Sixteen: Anchor Block

Although I devoted considerable attention to leveling & shimming the table under Mary’s HQ Sixteen, the machine rolls on ball bearing wheels atop (relatively) smooth plastic tracks. Parked at a few spots along the dozen feet of table, the machine will slowly and quietly roll away. This calls for some sort of parking brake, but until inspiration strikes, a simple anchor will suffice:

It’s a cocoa container chosen from (one of) my Boxes o’ Containers, with a husky chunk of steel atop some very sticky double-sided foam tape inside the red lid.

You can see one of the ball bearing wheel just above the strap applying tension to the practice quilt out of view on the left. The thing that looks like a wheel just under the strap is an encoder for the stitch regulator that we haven’t connected yet.

To prevent the machine from simply bulldozing the container along with it, the lid sits on a sheet of EVA craft foam stuck to a sheet of rigid foam board (with adhesive on both sides).

Scan the lid:

Select all the red pixels, do a little cleanup, turn it into a binary mask:

Import it into LightBurn, trace the perimeter, do some curve optimization / smoothing, duplicate the outline, set one to cut EVA foam and the other to cut adhesive board, and Fire The Laser.

Elapsed time: about fifteen minutes from realizing what was needed to plunking the anchor in place.

I briefly considered a full-frontal laser-cut finger-jointed box for the weight, but … Mary’s not a big fan of that campfire smell, particularly in a room dedicated to the Fiber Arts.

2024-12-04

Handi-Quilter HQ Sixteen: Front Handlebar Angled Mount

So as to not bury the lede, I remounted the front handlebar unit of Mary’s Handi-Quilter HQ Sixteen long-arm sewing machine so she can see the control panel with its small LCD:

HQ Sixteen - remounted handlebars in use — HQ Sixteen – remounted handlebars in use

The new and old white LEDs produce distinctly different colors and intensities on the practice quilt fabric.

The original HQ Sixteen design bolted squarely atop the arm:

HQ Sixteen - original front handlebar mount — HQ Sixteen – original front handlebar mount

The control surface is, admittedly, angled slightly forward, but Mary was unable to see the lower few lines of the LCD without standing on tiptoe.

Begin with a crude tracing of the mating surfaces:

Import the image into Inkscape and lay some shapes on it:

Front handlebar base layout - Inkscape — Front handlebar base layout – Inkscape

Import the SVG into LightBurn and cut templates to verify the hole positions:

HQ Sixteen - handlebar bolt templates — HQ Sixteen – handlebar bolt templates

Obviously that took more than one try.

Rationalize the outlines, clean things up, and organize the shapes into useful named layers:

Front handlebar base layout - Inkscape layers — Front handlebar base layout – Inkscape layers

Save as an Inkscape SVG, import into OpenSCAD, and extrude the layers defining all those shapes into a solid model:

Handlebar Base Mount - solid model — Handlebar Base Mount – solid model

That’s the most recent iteration; earlier ones appear in various pix.

I had intended to use either square nuts or heat-set inserts, but it turned out to be easier to just slam BOSL2 threaded nuts into the front plate and be done with it:

Handlebar Base Mount - solid model - hex nuts — Handlebar Base Mount – solid model – hex nuts

The trick is to sink the nuts around a hole sized slightly larger than the screw’s nominal diameter, letting the threads fill empty space.

The handlebar base is mounted symmetrically along the machine arm centerline aligned with the two screws on the right. The rear block is offset to the left to clear the machine cover on the right, so the hull() wrapped around the two looks weird.

The front plate stands proud of the rest by dint of incorporating only a small slice of its back face into the hull() filling the gaps between the two. It’s not particularly stylin’, but it’s pretty close.

Finding the correct angle for the front plate required a couple of iterations, but they all built successfully:

HQ Sixteen - handlebar mount - on platform — HQ Sixteen – handlebar mount – on platform

Putting the threaded holes vertical created nicely formed threads that accepted the screws without hassle.

The block screws firmly to the arm and the handlebar unit screws to the block:

HQ Sixteen - remounted handlebars - side — HQ Sixteen – remounted handlebars – side

The display now faces front:

HQ Sixteen - remounted handlebars - front — HQ Sixteen – remounted handlebars – front

I eventually replaced those black oxide screws with shiny stainless ones, just for pretty.

The nine LEDs under the display now do a great job of lighting up the front of the machine’s arm, rather than the fabric at the needle, but fixing that will be a whole ‘nother project.

The handlebar grips with their control buttons now tilt at a somewhat inconvenient angle, which is also a whole ‘nother project.

Early reports from the user community are overwhelmingly positive.

The OpenSCAD source code and the SVG layout as a GitHub Gist:

Sorry, something went wrong. Reload?

Sorry, we cannot display this file.

Sorry, this file is invalid so it cannot be displayed.

view raw Front Handlebar Layout.svg hosted with ❤ by GitHub

	// Handiquilter HQ Sixteen front handlebar base mount
	// Ed Nisley – KE4ZNU
	// 2024-11-22

	include <BOSL2/std.scad>
	include <BOSL2/threading.scad>

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

	HandlebarOffset = [0,-30.0,14.0]; // pure empirical values
	HandlebarAngle = [60,0,0];

	FrameBlockThick = 35.0; // how much meat they need
	HandlebarThick = 12.0;

	/* [Hidden] */

	Holes = [[-19.0,0,0],[0,0,0],[0,12.5,0]]; // Must match SVG hole coordinates

	FrameCenter = [-45,-65]; // coordinates of corner hole center
	HoleCenter = [-40,-20];


	Protrusion = 0.1;

	module AdapterBlock() {

	union() {
	hull() {
	linear_extrude(height=FrameBlockThick,convexity=10)
	translate(FrameCenter)
	import("Front Handlebar Layout.svg",layer="Machine Frame");

	translate(HandlebarOffset)
	rotate(HandlebarAngle)
	linear_extrude(height=0.05*HandlebarThick,convexity=10)
	translate(HoleCenter)
	import("Front Handlebar Layout.svg",layer="Handlebar Base");
	}

	translate(HandlebarOffset)
	rotate(HandlebarAngle)
	linear_extrude(height=HandlebarThick,convexity=10)
	translate(HoleCenter)
	import("Front Handlebar Layout.svg",layer="Handlebar Base");
	}
	}

	module AdapterHoles() {

	linear_extrude(height=FrameBlockThick,convexity=10)
	translate(FrameCenter)
	import("Front Handlebar Layout.svg",layer="Machine Holes",convexity=2);

	translate([0,0,FrameBlockThick – 7.0])
	linear_extrude(height=7.0 + Protrusion,convexity=10)
	translate(FrameCenter)
	import("Front Handlebar Layout.svg",layer="Machine Counterbore",convexity=2);

	translate(HandlebarOffset) // cut clearance for nut threads
	rotate(HandlebarAngle)
	linear_extrude(height=HandlebarThick + Protrusion,convexity=10)
	translate(HoleCenter)
	import("Front Handlebar Layout.svg",layer="Handlebar Holes",convexity=2);

	}

	module Adapter() {

	union() {
	difference() {
	AdapterBlock();
	AdapterHoles();
	}

	# translate(HandlebarOffset) // add threads inside holes
	for (c = Holes)
	rotate(HandlebarAngle)
	translate(c)
	threaded_nut(10.0,6.2,HandlebarThick,1.0, // flat size, root dia, height, pitch
	bevel=false,ibevel=false,anchor=BOTTOM);
	}
	}

	// Build things

	if (Layout == "Block")
	AdapterBlock();

	if (Layout == "Holes")
	# AdapterHoles();

	if (Layout == "Show")
	Adapter();

	if (Layout == "Build")
	rotate([180,0,0] – HandlebarAngle)
	Adapter();

view raw Handlebar Base Mount.scad hosted with ❤ by GitHub

2024-12-02

Quilting Ruler Rack: Expedient Base

Mary is at least the third owner of a steel rack, originally intended to hold packages of retail stuff, which now holds (much of) her collection of quilting rulers:

Quilting Ruler Rack Base - overview — Quilting Ruler Rack Base – overview

Obviously, it was never intended to hold heavy acrylic sheets, but it worked surprisingly well, right up to the point where too many of the rulers collected on two adjacent columns of pegs and overbalanced the whole affair atop her while she attempted to remove a ruler.

Subsequent accident recreation showed the rack toppled when the weight of the rulers on the two adjacent columns of hooks moved the center of mass outward, just inside the line between those feet, whereupon the slightest tug on a ruler pulled it over.

Measurements revealed the four legs do not sit on a square contact patch, are not parallel to the radii from the center point, and are not uniformly distant from the center. Rather than committing to a finished product, I made a cardboard prototype to verify a bigger base would solve the problem and I could capture all those feet.

You don’t have such a rack, so the exact dimensions don’t matter, but the LightBurn layout looks like this:

The disk is two cross-laid sheets for stiffness, with marks burned on the top to help align the feet more-or-less around the center point.

The oblong rings fit around the feet to capture them, so cut eight or twelve to make four stacks a bit taller than the wire diameter.

The H shape then glues atop the rings to hold the feet in place. They’re not removable, but a razor knife will eventually solve that problem.

I slobbered hot melt glue across the cardboard disks to hold them together, glued and aligned the rings where the feet dented the disks, stood the rack in the rings, and glued the H plates.

About an hour elapsed from the sound of the crash to the rack once again standing quietly beside the fabric cabinets.

We’ll run this for a while and eventually replace it with a plywood disk and screwed-in-place clamps for the feet, which will surely call for wood surface preparation / stain / seal treatment.

2024-11-27

Roof Rake

If they think you’re crude, go technical; if they think you’re technical, go crude. I’m a very technical boy. So I decided to get as crude as possible. These days, thought, you have to be pretty technical before you can even aspire to crudeness.
William Gibson — Johnny Mnemonic

Now that the trees have shed most of their leaves / needles, it’s time to get the accumulation off the roof edges. Fortunately, the upstairs windows overlook the biggest piles and, after I considered and rapidly rejected the notion of using the wind stick, Mary convinced me a roof rake would suffice by deploying a too-short broom.

After considering and rejecting several decreasingly elaborate variations of 3D-printed pole-to-pusher-plate adapter nonsense that almost involved our pole saw, this happened:

The wood pole comes from a left-behind assortment atop the garage’s open ceiling joists and the pusher plate comes from the cardboard box treasure trove.

A laser cutter makes close-fitting rings and hot-melt glue sticks those plates together with gleeful abandon:

The blue-and-white cardboard plate consists of two box flaps glued together, the glued-up stack of half a dozen rings transfers the torque from the plate to the pole, and the whole affair took the better part of fifteen minutes from idea to cool-enough glue.

It’s back on the garage joists for next year, unless we decide that pole has a higher purpose in life. Worst case, it loses two inches of length.

Bonus: Chore accomplished before the predicted weekend snowfall!

2024-11-21

Sears Sewing Table: Caster Pads

Mary’s much-improved / -repaired Sears Sewing Table wanted to move around on the wood floor in the Sewing Room, so I captured its casters in little pads:

Sears Sewing Table caster pad - installed — Sears Sewing Table caster pad – installed

A layer of 1 mm cork with PSA adhesive provides griptivity against the floor, a solid layer of 3 mm plywood spreads the wheel force over the cork, and a top ring of 3 mm plywood captures the wheel.

Which looked like this during gluing:

Sears Sewing Table caster pad - gluing fixtures — Sears Sewing Table caster pad – gluing fixtures

The scrap on the left served to align cork & plywood; it came from the plywood contributing the shapes. The ring around the cork is a glued-up pair of plywood rings (4 mm wide, outset from the perimeter of the pads) serving to align the two plywood layers.

Verily: time spent making a fixture is never wasted!

And having a laser cutter makes fixtures trivially easy, at least for simple fixtures like those.

2024-11-18

Laser Cutter: Fourth Corner Fix Summary

A discussion on the LightBurn forum about a large-format machine with a misaligned beam prompted me to think through the whole “Fourth Corner” problem and come up with this summary based on my beam realignment adventure:

Here’s what I think is going on, referring to the 4×8 foot (!) machine in that discussion and lightly edited to improve readability & fix minor errors …

Mirror 1 alignment gets the beam parallel to the Y axis, averaged over the gantry travel between front and rear. The path length variation on your machine is four feet.

Mirror 2 alignment gets the beam parallel to the X axis, averaged over the laser head travel from left to right. The path length variation on your machine is eight feet.

When the laser head is in the left rear corner, the total path length is maybe a foot or two. When it’s in the front right corner, the total path length is upwards of twelve feet.

The “Fourth Corner” problem comes from a slight angular misalignment of Mirror 1, because you (and I and everybody) must set it with a maximum path length around four feet (Mirror 1 to Mirror 2 with the gantry at the front end of the machine). But with the laser head in the right front corner, the path length (Mirror 1 to Mirror 3) is three times longer, so the error due to a slightly mis-set angle at Mirror 1 is correspondingly larger.

A tiny tweak to Mirror 1 changes the spot position at Mirror 2 by very little, but moves the spot at Mirror 3 by much more due to the longer path length.

Tweaking Mirror 1 cannot compensate for a warped machine frame, but it will get the beam alignment as good as it can be made.

The next point of contention was my “middle of the mirror” suggestion. AFAICT, the spot burned into the target at each mirror marks only the useful part of the beam with stray energy in a halo around it. Centering the spot keeps that stray energy away from the mirror mounts, so it doesn’t cause unnecessary heating. This will be particularly important with a high-power laser.

Angular adjustment of each mirror puts the beam parallel to the axes, but cannot also center it on the mirrors. After it’s aligned, the path from the laser tube through the nozzle depends on the position of the tube relative to the nozzle: moving the tube up/down and front/back moves the beam position on the mirrors and through the nozzle, but (in an ideal world) doesn’t change the angular alignment.

So after aligning the beam parallel to the axes, you must move the laser tube, the mirrors (up/down left/right front/back), and maybe the laser head to center the beam in the mirrors and also in the nozzle. Because we don’t live in an ideal world, moving any of those pieces wrecks their angular alignment, so it’s an iterative process.

The goal is to reach this point:

Beam Alignment - Mirror 3 detail - 2023-09-16 — Beam Alignment – Mirror 3 detail – 2023-09-16

Those are five separate pulses, one each at the four corners and center of the platform.

The beam then goes pretty much through the center of the laser head and lens:

Beam Alignment - Focus detail - 2023-09-16 — Beam Alignment – Focus detail – 2023-09-16

Works for me, anyhow.

2024-11-13