Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
Vassar College sent a plow along the walking path linking the campus with the faculty enclave on Old Silvermine Place, but the clearance between the lamp pole and the boulder blocking the entrance wasn’t quite adequate.
Some days later, the light fixture was missing and the power cable sported three cheerful wire nuts:
Damaged pole – wire nuts
Another pole has been lying flat on the ground for (at least) the last two years and I’ve always wondered if its wires (within easy reach) were live under their nuts. Knowing the lamp power is 277 VAC from a 480 VAC three-phase service, I’m disinclined to find out.
The business end of a cheap stick blender we bought a year ago to replace the previous stick blender (*):
Fresko stick blender
This one failed just slightly beyond the duration of its one-year warranty, apparently with one of the shaft bearings seized to the extent of making the blade un-turnable even by (carefully protected) finger force.
With nothing to lose (and a new blender inbound), it stood in the Basement Shop in that orientation for a week while I dripped penetrating oil around the shaft and wiggled the blade slightly back-and-forth. The bearing eventually broke free and the blade turned reluctantly.
Still having nothing to lose, I gave the shaft a few shots with a drift punch, moving it a few millimeters in each direction. This apparently disturbed the seized bearing just enough to let it turn less reluctantly, with more penetrating oil improving the situation.
Mixing a jar of water went well, even on high speed, but I doubt the bearing is in good health. We decided a blender with penetrating oil tucked up inside should be disqualified for food processing.
When it first locked up, I bought a significantly more expensive stick blender, knowing full well more money does not imply better design / better materials / more QC. This one is now designated as a Cold Backup blender for garden & shop use.
(*) For the record, my 3D printed shaft adapter failed while converting garden tomatoes into thick & zesty pizza sauce. I’m unsurprised PETG-CF wasn’t up to the task.
Our house came with several single-LED night lights featuring a transparent light guide / reflector:
Nightlight light guide – original
The plate had snapped off one of them and, being me, I wondered if I could replace it with something similar.
Years passed.
Obviously, this must be made from a transparent substance, which 3D printed things are not, but after some fiddling with parameters I thought the result might be informative.
The guide plate is a section of a spherical surface, here approximated by a BOSL2 spheroid():
Nightlight light guide – view side – solid model
The original is 3 mm thick, but 2 mm worked out better for my purposes by reducing the amount of infill:
Nightlight light guide – wall side – solid model
The intricate base latches into the lamp’s plastic case:
Nightlight light guide – base – solid model
The result is, at best, translucent, because it’s definitely not transparent:
Nightlight light guide – translucent vs transparent
The zigzag pattern seems to come from the icosohedral approximation to the sphere, because it follows the surface tesselation.
Getting the base shape right required several iterations, each printed with the model cut off just above the bottom of the guide plate:
Nightlight light guide – test pieces
The first two attempts needed attention from a flush cutting pliers before fitting into the case, but they don’t call it rapid prototyping for nothin’.
The original and replacement plugged into an outlet strip:
Nightlight light guide – original vs printed on outlet strip
While you can see the vague outline of the strip behind the printed light guide, it’s definitely lacking in detail:
Nightlight light guide – outlet strip detail
The striations throw more light into the room than the original:
Nightlight light guide – printed
Fiddling with the 3D printing parameters might make it more transparent, but it’s going back into the box it came from after giving me a better idea of which parameters to tweak the next time around.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
As a reminder for the next time in this rodeo, the latches holding the temperature adjustment knob on the Delta 17 Series dual-handle bath / shower faucet look like this:
Delta bath faucet cap latches
I am unable to apply enough force to the smooth edge of the knob opposite the handle to un-latch it, so I jammed a small prydriver into the gap and twisted enough to pop the latch, at the obvious risk of scarring the chrome plating.
A better approach would involve a plastic prydriver intended for consumer electronics case cracking.
For the record:
Unlike the other bath faucets, this one has shutoff valves inside the wall
One of the inline switches I installed to replace the failed switches for the LED lights got unpleasantly warm enough to prompt an investigation:
Inline lamp switch – heat damage
Yeah, that is not a nominal outcome, particularly in light of the claimed “10 A 250 V” rating.
The overheated plastic pulled back enough to expose the terminal inside:
Inline lamp switch – visible terminal
There was a reason I’d wrapped those switches with known-good 3M electrical tape before deploying them.
That crimp connector took some heat and its screw looks even more unhappy:
Inline lamp switch – internal damage
It turned out the screw was an itsy too short to compress both the connector and the bent-metal conductor tab against the terminal block:
Inline lamp switch – misfit screw terminal
A 6 mm brass screw with a brass washer did a better job of compressing all parties into one conductive lump.
Although the switch now runs with the case at normal basement temperature, an allegedly UL listed replacement is on its way; it costs about five times more than that switch. If it behaves as it should, I’ll preemptively replace two other switches.
Unbelievably, the ankle zipper tab broke off in my hand:
Wind Pants Zipper Tab – broken
It’s one of those zippers where the tab releases a lock preventing the zipper from coming unzipped. Mary noped out of removing and replacing the entire zipper.
Trimming a snippet of aluminum miniblind from the Small Box o’ Flat Stuff and two dots of JB Kwikweld epoxy seemed appropriate:
Wind Pants Zipper Tab – clamping
Ugly, but serviceable:
Wind Pants Zipper Tab – repaired
The stray epoxy scraped off under fingernail pressure over the next two days and the pants are ready for the next snowfall.
The Smell of Molten Projects in the Morning 