Author: Ed

The proof of concept coaster might suffice for a shot glass, but my morning tea comes in a 20 ounce mug with a much larger footprint.

So, back to the Basement Shop, where a laser-cut and -engraved layout guide helps arrange and carry some suitable fragments:

As before, scan the bottom of the fragments and wrap selections around them:

Apply the usual operations to get a suitable mask:

Fire the laser to cut the chipboard test template holding the fragments, then a white octagonal acrylic base plate and a transparent acrylic layer surrounding the fragments, and:

Mix up some pourable epoxy, smooth it over the base plate, squish the transparent layer atop it, use the tape (sticky side up) to hold the two layers in alignment, and gently insert the fragments:

I eased some epoxy around the perimeter of each fragment with a pipette in an attempt to reduce the glass-sliver hazard:

Yes, that’s on top of the protective paper, because then I can whisk the paper off to reveal the pristine surface around each fragment:

As with the smaller coaster, the epoxy penetrates the fractures and reduces the shattered appearance. Mary suggests tinted epoxy would produce an interesting effect and I’ll try that the next time around.

Because the smashed glass came from our neighbor’s lawn, it carried a bit of dirt and debris onto the playing field:

Seen through the edge of the coaster, the uneven surface of the epoxy fill around the fragments shows up clearly:

The top of the glass stands half a millimeter above the transparent acrylic. I knew that would happen and wanted to see how the bottom of the mug interacted with the epoxy-coated sides:

As it turned out, the epoxy coating wasn’t quite good enough to prevent tiny slivers from chipping off and, in the cold light of day, the pale-green-ish tinted glass didn’t stand out well against the white background.

So I taped up the perimeter, leveled the base, mixed up another batch of epoxy, added two drops of opaque black dye, and poured just enough to level the surface with the glass:

Introducing the meniscus to Mr Belt Sander put a bevel around the edge and finished it off well enough:

The Squidwrench logo looks a bit battered after three and a half years of trips through the dishwasher, although I didn’t expect it to last nearly this long.

There’s still a slight upward tilt around the perimeter, but it meets my simple requirements and the fragments definitely look better in black. The white base sets off the fragments, but a clear plate takes advantage of their transparency; a mirror sheet might be even more interesting.

If you’re a particularly sharp person, these may accentuate your wardrobe:

They’re fragments of smashed tempered glass, epoxied into laser-cut disks, with a ring providing some structural support. Although it’s hard to tell from the photos, the fragments sit flush with one side of the disk, which is likely the side you want closest to your carotid artery:

Each chunk consists of a few smaller cuboids, so you get internal reflections from the minute air gaps between them. They’re not diamonds, but they’re surprisingly glittery in the proper light. Bonus: you can see right through!

The “gold” band around the disk is a beading ring held in a notch engraved around both disks:

The smaller ring is 12 mm OD, the larger is 25 mm, with 16 mm (the descriptions says 15, but ya get what ya get) and 20 mm available for other glass fragment sizes.

The engraved recess (green) is slightly larger than the OD to allow the perimeter cut to proceed through a thinner section:

Cross-hatch engraving puts a steep edge all around the recess, so the ring fits with just a little slack and turns freely around the disks.

You will, of course, have different glass fragments requiring different shapes, but the outlines came from the same process I used to make the palette organizing the fragments:

You (well, I) can just import that layout, copy the outline of the chunk to be used, then delete the rest. Mirror the outline so the engraved sides of the disks fit together around the chunk, position symmetrically in the template halves, and fire the laser.

Affixing the fresh-cut disk and its glass chunk to a strip of Kapton tape (sticky side up) holds them in proper alignment and prevents the epoxy from leaking out the bottom:

With everything lined up, run a small bead of epoxy around the chunk, squish the top disk in place, and line up the notches. When the epoxy cures, peel the earring off the tape and slide a jump ring into the notch.

As a finishing touch, you’d add a suitable ear hook or stud, but I think it’s fair to assume anything from Amazon would consist of the finest arsenic-plated plutonium and be completely unsuitable for skin contact. Neither of us have any piercings, so I cannot provide enticing action photos.

The 25 mm versions failed because I made the outlines such a snug fit around the chunks they didn’t quite fit:

Protip: do not attempt to coerce two rigid bodies into alignment by applying firm pressure, particularly when one of them is already-broken glass.

The small earrings weigh 0.7 g each and a 25 mm one (well, the parts for a large one) comes in a bit over 3 g, plus whatever hardware goes in / on / around your ear.

This was (obviously) an exercise in small-scale laser machining, rather than a venture into haute couture. In the highly unlikely event you can’t live without a pair of custom-designed high-impact earrings, I’ll shut up and take your money … let me know if you want little or big. Black is the new black; I do have other colors, but who are you kidding?

The SVG images as a GitHub Gist:

Having a myriad small glass fragments and an idea for their use created the problems of organizing the pieces while not losing them under the bench.

As with the shattered shot-glass coaster, start by lining up the suspects on the scanner:

Blow out the contrast, flip right-to-left, then mask them en masse:

Delete the images (inside their selection masks) to create a binary mask:

Have LightBurn trace the binary images, wrap a rounded rectangle around the lot of them, duplicate the rectangle as a base plate, then fire the laser:

They’re not secured in their sockets, but they won’t fall out unless I fat-finger the whole affair:

The thing that takes getting used to: the whole process was about two hours of wall clock time from start to finish, with a leisurely breakfast and KP in the middle.