Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
So I picked up the frequency counter and found this:
FC1002 Frequency Counter – split shattered faceplate
The outer, previously cracked pieces of the faceplate split parallel to the front panel, separating into two layers, and popped free of their mount. The layer closest to the panel remains intact.
The fragments were flexible and the bottom layer was rigid, suggesting the faceplate consisted of two parts, perhaps an acrylic (?) base with a soft silicone (?) poured atop it for armor and scratch protection.
It still works fine and the acrylic (?) layer will suffice for my simple needs, despite being slightly marred by the cyanoacrylate glue I slobbered into the cracks.
Steelcase lists the arm rests on their Leap chairs as “factory installed” and not removable, perhaps because the brackets supporting the arms also support the backrest. In the event you must ever remove the arms, perhaps because your wife decides she’d like to try the chair without them, it’s straightforward.
Loosen the Torx screw visible through the slot in the bottom of the plastic shroud about a dozen turns (it will not click or feel loose), use a flat screwdriver to unlock the shroud from the flat plastic plate on the seat side of the bracket, then forcibly pull the sides of the shroud outward until you can pull the arm extension mechanism up-and-out of these slots in the bracket:
Steelcase Leap – arm bracket
This view from the side of the chair shows the screw hole in the bottom, with a pair of holes for alignment pins beside it:
Steelcase Leap – arm bracket
You can remove the flat plate by pushing the latch at the top center (just below the backrest screw boss), then sliding the plate upward.
As nearly as I can tell, there’s no way to remove the shroud from around the arm extension mechanism, so you must pull off the whole thing in one lump:
Steelcase Leap – arm mechanism
The two pairs of slots in the edges of the shroud engage tabs on the plastic plate; that’s why you need the flat screwdriver.
The two pins on the bottom lock the arm into the bracket: you must raise it vertically until those come out, after which you can ease the bottom outward until the pins on the sides (which you can’t see inside the shroud) disengage from the bracket slots.
It takes a whole lot more force than seems necessary, but it can be done.
Wrap Gorilla tape around the raw edges until you decide whether it’s worthwhile to design and print a pair of plastic caps to cover the whole bracket.
While installing new underseat packs (about which, more later) on my Tour Easy, I discovered a bight of PTT cable had been touching the top of the chain:
Eroded PTT cable – Tour Easy
The gentle ripples to the right of the worn-through section seem particularly nice; you couldn’t do that deliberately if you had to.
This section of cable should have been taped to the upper frame bars. It’s hidden under the seat, just in front of the rear fender, and between the under-seat packs, so it’s basically invisible from any angle.
Soooo, that probably explains a bit of the intermittent trouble I’d been having with the PTT switch, although most of it came from the corroded switch contacts.
Rather than replace the whole cable, I cut out the eroded section, spliced the conductors, and taped it firmly back on the tubes.
The case from a Dell Optiplex GX270 will hold the Kenmore 158 sewing machine’s motor control electronics, because it has a well-grounded metal box inside the plastic shell that will protect fragile humans from line voltages. The GX270 power supply will suffice for the usual stuff, but the bridge rectifier, power transistor, and suchlike require a direct connection to the AC line.
Rather than add another plug, I soldered a nice two-wire line cord to the IEC socket terminals inside the GX270’s power supply:
Modified Dell power supply – interior
The cord follows the IEC/EU standard color code:
Blue – neutral
Brown – hot
The power supply follows the US standard color code:
The yellow cable tie anchors the cord to a metal tab that, when bent at right angles, provides a convenient exit from the power supply at exactly the right location:
Modified Dell power supply – AC cord exit
The power supply mounts with the label facing inward, directly adjacent to the PCI slot covers. The new cord emerges near the bottom, inside the recess that formerly accommodated the board.
Definitely not UL approved, but we’re well beyond that stage anyway…
The desiccant definitely lasts longer during the winter, even though the dehumidifier fights the basement air to a standstill around 55%RH during the summer.
Each desiccant bag contains 500 g of silica gel and the most recent one adsorbed 73 g of water.
Mary bought a pair of Revlon tweezers a while ago, picking a Name Brand to avoid hassles with bottom-dollar crap:
Revlon tweezers – bad spot welds
Well, that didn’t work.
I contend that the only difference between Name Brands and the bottom-dollar crap I tend to buy is a bit of QC and a lot of price. I’ll agree that’s not strictly true, but it does fit a goodly chunk of the observed data.
Anyhow.
I milled a recess into the corner of some scrap plastic to locate the handle end, then arranged a step block to capture the business end:
Revlon tweezers – drilling setup
That setup ensures the holes go into the corresponding spots on both pieces, because I couldn’t figure out how to clamp them together and drill them both at once. I drilled the other piece with its good side up to align the holes; doing it bad side up would offset the holes if they’re not exactly along the center line.
A closer look:
Revlon tweezers – drilling fixture
Talk about a precarious grip on the workpiece!
I filed the welds flat before drilling, so the pieces lay flat and didn’t distract the drill.
Then:
Center-drill
Drill 2-56 clearance
Scuff up mating surfaces with coarse sandpaper
Apply epoxy
Insert screws
Add Loctite
Tighten nuts to a snug fit
Align jaws
Tighten nuts
Fine-tune jaw alignment
Apply mild clamping force to hold jaws together
Wait overnight
Saw screws and file flush
Done!
The clamping step:
Revlon tweezers – epoxy curing
Those nicely aligned and ground-to-fit jaws were the reason Mary bought this thing in the first place.
The screw heads look OK, in a techie sort of way:
Revlon tweezers – fixed – front
The backside won’t win any awards:
Revlon tweezers – fixed – rear
But it won’t come apart ever again!
There’s surely a Revlon warranty covering manufacturing defects, printed on the long-discarded packaging, that requires mailing the parts with the original receipt back to some random address at our own expense.
These sunglasses fit Mary’s face and do a good job of keeping road grit out of her eyes, but she doesn’t like the extended earpieces. So I cut ’em off:
Ironman sunglasses – trimmed earpieces
The trick is to shape the ends with an ordinary diagonal cutter, then round the edges with sandpaper.
The lower pair has seen a few years of use, during which the bright yellow plastic faded quite a bit.
Nothing profound, other than that you need not put up with nuisances.
The Smell of Molten Projects in the Morning 