Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
A recent Amazon purchase of three 3 lb bags of walnuts from a known-good seller arrived with many damaged nuts:
Damaged walnuts – detail
The damage matches what I read about Walnut Husk Fly infestations: shriveled kernels and terrible taste.
In round numbers, I found 8 oz of damaged nuts in each 3 lb bag, enough to ruin the entire batch. The seller immediately refunded the purchase price for all three bags, so there’s that.
It’s definitely not one of the counterfeit products plaguing Amazon, but I wonder why that lot didn’t fail incoming inspection.
I’m loathe to buy more walnuts for a while, though.
Memo to Self: Always inspect incoming purchases, even from reputable sellers!
I started low-key upper-body strength training in June with encouraging results: my biceps no longer require exotic instrumentation for detection and my abs may soon transition from “throw pillow” to “two-pack”.
This is, however, the season of bounteous garden harvests, including delicious corn-on-the-cob and summer squash …
Verily, given the right tools, any job becomes do-able:
New Utility Pole – installing
It was fascinating for me and just another day at the office for everybody else:
New Utility Pole – wiring
They nailed the original pole tag to the new pole, complete with the original 1940 nail:
New Utility Pole – pole tag 144701
I expect this pole will outlive me, just as the original pole outlived the folks who built our house.
The most memorable comment came from the person doing the CHG&E damage assessment, who really really wanted this to not be their problem: “Anybody could steal a pole tag and nail it on that pole.” I asked what location their records showed for the pole tag, whereupon the conversation moved on.
Second-place award: no, we were not interested in trenching underground lines 300 feet along the property line, at our expense, to avoid an “unsightly” pole.
For unknown reasons, I was supposed to figure out which telecom utilities had wired the pole, notify them, and wait for them to tack their cables to the new pole. I called both Verizon and Altice / Optimum, got service tickets, and watched them close the tickets without further action. I tried re-opening the Verizon ticket and was told somebody would be there within 48 hours. An Optimum guy showed up, promised a quick return visit from a team with proper equipment, but nothing happened.
I suppose having no customer at the end of the cable removed any motivation to clear their hardware off our lawn, so, after two weeks, I deployed the bolt cutter, rolled up the cables, and scrapped ’em out.
I got an email asking how the Kenmore Model 158 sewing machine’s foot pedal pivots worked. The notes on rebuilding the carbon disk rheostat and conjuring a Hall effect sensor show the innards, but here’s what you need to know to get there.
The pedal has a pair of pivots on the side closest to your foot, held in place with a small screw inside the two feet:
Kenmore 158 – Pedal pivot screw – in place
The screw fits into a notch in the unthreaded pin inserted from the side:
Kenmore 158 – Pedal pivot screw – disassembled
And that’s all there is to it!
Now, as happened to my correspondent, the pin can go missing, perhaps after the screw worked loose. Worst case, you’re looking at replacing both parts.
Being made in Japan (as ours were), the pedal has metric sizes: the unthreaded pin is 4 mm in diameter and 18 mm long and the setscrew has an M4×0.7 thread. You could replace the pin with an 18 mm (down to maybe 15 mm) long M4 screw. The threads would make a gritty pivot, but better than no pivot at all.
Better to get a longer M4 screw with an unthreaded section near the head, hacksaw it to the proper length, file to tidy up the cut end, maybe file a notch for the setscrew, and pop it in place. For tidiness, file off the slot / Philips / hex socket to eliminate the temptation to turn it out.
Worst case, a pair of plain old USA-ian 6-32 screws 3/4 inch long would make a sloppy fit. Don’t tell anybody I said so; that’d be barely better than nothin’ at all in there.
Lowe’s claims to have M4×0.7 setscrews (with a hex socket, not a slot) to secure the pin.
If my experience around here is any guide, however, Lowe’s / Home Depot / Walmart may claim to have metric hardware in stock, but the only way to know is to actually go there and rummage around in the specialty hardware section, inside the big steel cabinet with slide-out drawers filled with a remarkable disarray of ripped-open bags and misfiled parts.
Since the PiHole runs all the time, it now hosts an FTP server to stash snapshots from the cameras onto a 64 GB USB stick. I installed ProFTPD, which Just Worked with a few configuration tweaks:
UseIPv6 off
ServerName "PiHole"
DefaultRoot /mnt/cameras
RequireValidShell off
ftp_snapshot=true
ftp_host="192.168.1.2"
ftp_port=21
ftp_username=$(/bin/hostname)
ftp_password="make up your own"
ftp_stills_dir=$(/bin/hostname)
The last line uses a separate directory for each camera, although they quickly ran into the FAT32 limit of 64 K files per directory; reformatting the USB stick with an ext3 filesystem solved that problem.
My high hopes for the UHMW bushing supporting the impeller lasted the better part of a day, because direct contact between the impeller and the motor bearing produced an absurdly loud and slowly pulsating rumble:
Bath Vent Fan – bushing installed
My hope that the UHMW would wear into a quieter configuration lasted a week …
Back in the Basement Shop, some free-air tinkering showed the impeller produced enough suction to pull itself downward along the shaft and jam itself firmly against the motor frame. My initial thought of putting a lock ring around the shaft to support the impeller turned out to be absolutely right.
So, make a small ring:
Bath Vent Fan – small lock ring – c-drill
With a 4-40 setscrew in its side, perched atop the impeller for scale:
Bath Vent Fan – small lock ring – size
It just barely fits between the impeller and the motor frame:
Bath Vent Fan – small lock ring – installed
This reduced the noise, but the hole in the impeller has worn enough to let it rotate on the shaft and the rumble continued unabated. The correct way to fix this evidently requires a mount clamped to both the shaft and the impeller.
Fast-forward a day …
A careful look at the impeller shows seven radial ribs, probably to reduce the likelihood of harmonic vibrations. After a bit of dithering, I decided not to worry about an off-balance layout, so the screws sit on a 9 mm radius at ±102.9° = 2 × 360°/7 from a screw directly across from the setscrew in another slice from the 1 inch aluminum rod:
Bath Vent Fan – mount ring – tapping
Centered on the disk and using LinuxCNC’s polar notation, the hole positions are:
As usual, I jogged the drill downward while slobbering cutting fluid. I loves me some good manual CNC action.
Put the mount on a 1/4 inch tube, stick it into the impeller, and transfer-punch the screw holes:
Bath Vent Fan – mount ring – impeller marking
Apparently, some years ago I’d cut three screws to just about exactly the correct length:
Bath Vent Fan – mount ring – test fit – bottom
I knew I kept them around for some good reason!
The 9 mm radius just barely fits the screw heads between the ribs:
Bath Vent Fan – mount ring – test fit – top
Some Dremel cutoff wheel action extended the motor shaft flat to let the setscrew rest on the bottom end:
Bath Vent Fan – mount ring – shaft flat
Then it all fit together:
Bath Vent Fan – mount ring – installed
The fan now emits a constant whoosh, rather than a pulsating rumble, minus all the annoying overtones. It could be quieter, but it never was, so we can declare victory and move on.
Dropping fifty bucks on a replacement fan + impeller unit would might also solve the problem, but it just seems wrong to throw all that hardware in the trash.
And, despite making two passes at the problem before coming up with a workable solution, I think that’s the only way (for me, anyhow) to get from “not working” to “good as it ever was”, given that I didn’t quite understand the whole problem or believe the solution at the start.
But it should be painfully obvious why I don’t do Repair Cafe gigs …
The Smell of Molten Projects in the Morning 