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.
Growing and sometimes fixing
As fate would have it, the Step2 rolling garden seat took an untimely fall while standing in the garage and broke both its hinges:
It’s been out in the garden for maybe six years, so those chunks of plastic are fully depreciated.
Two hours after loading the solid model into PrusaSlicer:
The SiLite tray is well-weathered, but remains structurally sound: still ready for service in the D-Hall breakfast line on the morning after the Apocalypse.
Living in the future works out pretty well.
The cart in Mary’s Vassar Farm plot returned in need of repair:
Those fractures near the end of the axle let the axle erode the side wall:
This will obviously require some sort of reinforcement on the body holding the axle, but the first challenge involved getting the wheels off the axle:
Some brute force revealed the hub covers snapped over an install-only locking fastener:
More brute force cut those fasteners (a.k.a. star-lock washers) to get the wheels off the axles.
While contemplating the situation, a box of 606 bearings (as used in the PolyDryer auto-rewind spindles) failed to scamper out of the way and produced a victim fitting perfectly on the 8 mm axle:
I regard such happenstance as a message from the Universe showing I’m on the right track. The alert reader will note the axle should not rotate, but does sport scars showing it’s done some turning in the recent past, so the bearing may not be a completely Bad Idea™.
Finding a Lexan snippet exactly as thick as the bearing suggested bolting a plate across the side of the body to support the bearing, like this:
Some layout work in LightBurn produced a template to mark the body for hand-drilling the holes:
In retrospect, that was a mistake. I should have:
Instead, three of the holes in that nice Lexan sheet ended up slightly egg-shaped to adjust for mis-drilled holes in the body.
Lexan does not laser-cut well at all, so that sheet was drilled to suit after using the template to mark the holes:
Then it got bandsawed / belt-sanded into shape.
I squeezed 5 mm rivnuts into whatever fiber-reinforced plastic they used for the body, which worked better than I expected. They’re intended for sheet metal, so I set the tool for 5 mm compression and they seem secure. I hope using plenty of screws across a large plate will diffuse the stress on each screw.
Then I threaded the axles and used acorn nuts:
In this situation, I regard JB KwikWeld epoxy as “removable with some effort”, as opposed to the destruction required with those star-lock washers. High-strength Locktite might also be suitable, but I do not anticipate ever having to remove these again for any reason and do not want the nuts to fall off in the garden.
The re-replaced seat conjured from a cafeteria tray continues to work fine, as do its 3D printed hinges.
It’ll reside in the shed until Spring rolls around …
A knife found in Mary’s Bucket o’ Gardening Gear was in need of a sheath:
Unlike the time before or the time before that, a few minutes with LightBurn laid out the overall pattern:
The knife’s silhouette came from a few minutes with GIMP, because cleaning up the edges on a graphics tablet is easier than fiddling with precise spline curves. Export the selection as an SVG, import into LightBurn, set to Fill, and Fire The Laser:
The upper block in the LightBurn layout is an oversized rectangle so I could cut that out first, stick craft adhesive on both sides, trim the edges, drop it back into the hole, then cut the middle part of the sheath.
It’s made of recycled through-dyed chipboard and it won’t last forever, but that’s not a problem because these things tend to wander off before they disintegrate.
I must do a few more for the other garden bucket, but those should be straightforward.
Despite freezing the kitchen scraps going into the worm bin since the previous fruit fly infestation, a zillion flies are now in residence. Lacking the peppermint-stick tube of yesteryear, I conjured another fly trap from common household items:
The gap around the top got a strip of tape after I took the picture.
The gallon jug has cardboard stiffeners supporting a sheet of the sticky paper I used for the onion fly traps:
I was all set to 3D print a threaded adapter to join the two bottles when I realized they already had lids. A few minutes of lathe work added a passageway:
They’re held together by a generous ring of hot melt glue:
The LED strip provides enough light to simultaneously attract the flies and repel the worms.
The laser cuttery looks like this:
The white shape in the black block is a scan of the cut-open jug, with the other shapes in that row being rectangularized versions. The two tiny notches in the Top and Bottom shapes hold the sticky paper.
The two rings at the top adapt the LED-wrapped bottle to the existing fitting on the worm bin from the previous episode. They’re visible as shadows near the bottom of the bottle.
The circle is a laser-cut hole in the gallon jug bottom for the screened plug made for the pepermint-stick tube; the less said about that operation the better.
So far, so good, although previous experience suggests the flies will be breeding ahead of their (considerable) losses for the next few weeks.
One of Mary’s gardening buddies gave her a Taylor rain gauge he picked up at a closeout sale, but the exceedingly thin aluminum holder obviously wasn’t up to the task:
I briefly considered 3D printing a better bracket, but came to my senses:
A generous fillet of tan JB PlasticBonder holds the thin aluminum clamp ring to the top of the dagger spike:
The spike is 6.3 mm acrylic and should survive for a while despite the stress-raiser corners. The next iteration will have radiused corners and could last longer:
The holes will fit 4 mm screws, although the OEM holder isn’t good for more than 3 mm.
The LightBurn SVG layout as a GitHub Gist:
Took longer to write it up than to do it, even counting mixing the adhesive.
Replacing the sun-rotted hose for Mary’s garden called for a new grip, because of course all hose fittings are different:
The ridges on the fitting looked close enough to half-cylinders and the fitting wasn’t tapered enough to worry about:
The OD came from the original grip, because it neatly fits Mary’s hand, and the nubbles are round-end cylinders.
Got it done the day after the old hose split, glued it on the hose with E6000+, installed it the next morning, whereupon the weather delivered three inches of rain. It’ll get screwed onto the faucet in a few days …
The OpenSCAD source code as a GitHub Gist:
| // Hose fitting grip – simple plastic extrusion | |
| // Ed Nisley – KE4ZNU | |
| // 2025-07-30 | |
| include <BOSL2/std.scad> | |
| /* [Hidden] */ | |
| HoleWindage = 0.2; | |
| Protrusion = 0.1; | |
| NumSides = 3*2*4; | |
| $fn=NumSides; | |
| ID = 0; | |
| OD = 1; | |
| LENGTH = 2; | |
| NumRibs = 8; | |
| RibOD = 3.0; | |
| GripOA = [32.5,66.0,16.0]; | |
| KnobBallOD = 6.0; | |
| union() { | |
| difference() { | |
| tube(GripOA[LENGTH],id=GripOA[ID],od=GripOA[OD],orounding=2.0,anchor=BOTTOM); | |
| for (a = [0:NumRibs-1]) | |
| rotate(a*360/NumRibs) | |
| right(GripOA[ID]/2) down(Protrusion) | |
| cyl(GripOA[LENGTH] + 2*Protrusion,d=RibOD,anchor=BOTTOM); | |
| } | |
| for (a = [0:NumSides-1]) | |
| rotate(a*360/NumSides) | |
| right(GripOA[OD]/2) | |
| up(GripOA[LENGTH]/2) | |
| cyl(GripOA[LENGTH]/2,d=KnobBallOD,rounding=KnobBallOD/2); | |
| } |
I salvaged a solar garden light from the Vassar Community Gardens midden heap and stripped it down:
The single IC is a YX805 “solar lawn light boost control chip” and the resistor-like thing is a 82 µH inductor setting a 13 mA input current.
Cleaning off some minor corrosion, charging the NiMH cell, and soldering an amber LED onto the pigtail wire brought it back to life.
It’s now perched on the porch railing where it catches some afternoon rays:
Maybe we can think of something better for it to do …
The Smell of Molten Projects in the Morning 
