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.
If it used to work, it can work again
My buddy dBm took pity on my plight:
The far end has a 2.5 mm hex driver, although I’ve never encountered a nut for an M1×0.25 screw in the wild. It doesn’t fit an 0-80 nut and gulps 00-90 nuts, so it’s definitely hard metric.
My collection of glasses required an aggregate two turns of tightening, which prompted dBm to remind me of threadlock.
Done!
Thank you, dBm!
During an evening KP session, the kitchen faucet handle jammed at the clockwise (hottest) end of its travel and refused to turn; it continued to move vertically and I turned off the water. This had happened before, so I knew roughly what to expect:
The pointer on the red hot limit safety stop ring should be aimed just right of the front screw, at the 0 position producing maximum hotness. The scale reads backwards, perhaps in units of increasing safety.
In that position, the ring prevents the valve core from turning counterclockwise, which explains the symptoms. With the water turned off (at the ball valves in the basement) and the valve stub tilted vertically, the ring popped loose (it shouldn’t move on its own) and exposed the problem:
Neither Mary nor I recall applying that much force to the handle, but ya never know.
The flanges protruding from the stem prevent you from removing the ring, but a pair of small diagonal cutters will chop right through the plastic. If you’re one of the six people depending on the limit stop to keep the water temperature under control, you probably don’t want to cut the ring out; I have no suggestions on how to repair it.
It’s obvious the splines won’t ever be the same again:
The ring has two sets of splines and they’re both wrecked:
With the ring out of the way, it’s easy to see the trunnion shaft has moved leftward:
There’s essentially no clearance between the shaft and the ring, so it was rubbing against the ring, as evidenced by the red debris left behind when I tapped it to the far end of its travel:
Reassemble in reverse order and it works fine again.
I expect the shaft will resume moving leftward and eventually jam in the notch, probably after abrading the white plastic, but I don’t see how to lock it in place.
A new-to-me Dell Optiplex 9020 needed a BIOS update, which, as always, arrives in a Windows / DOS EXE file. Because I’d already swapped in an SSD and installed Manjaro, I had to (re-)discover how to put the EXE file on a bootable DOS USB stick.
The least horrible way seemed to be perverting a known-good FreeDOS installation image:
sha256sum FD12FULL.zip
fd353f20f509722e8b73686918995db2cd03637fa68c32e30caaca70ff94c6d2 FD12FULL.zipUnzip it to get the USB image file, then find the partition offset:
fdisk -l FD12FULL.img
Disk FD12FULL.img: 512 MiB, 536870912 bytes, 1048576 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000
Device Boot Start End Sectors Size Id Type
FD12FULL.img1 * 63 1048319 1048257 511.9M 6 FAT16Mount the partition as a loop device:
sudo mount -o loop,offset=$((63*512)),uid=ed FD12FULL.img /mnt/loopSee how much space is left:
df -h /mnt/loop
Filesystem Size Used Avail Use% Mounted on
/dev/loop0 512M 425M 87M 84% /mnt/loopThe image file is 512 MB and has 87 MB available. The BIOS file is 9.5 MB, so copy the file to the “drive”:
cp O9020A25.exe /mnt/loopWhich knocks the available space down by about what you’d expect:
df -h /mnt/loop
Filesystem Size Used Avail Use% Mounted on
/dev/loop0 512M 435M 78M 85% /mnt/loopUnmount the image “drive”:
sudo umount /mnt/loopCopy the image file to a USB stick:
sudo dcfldd status=progress bs=1M if=FD12FULL.img of=/dev/sdg
512 blocks (512Mb) written.
512+0 records in
512+0 records outPop the USB stick in the Optiplex, set the BIOS to boot from “Legacy” ROMs, whack F12 during the reboot, pick the USB stick from the list, and It Just Works™:
We have a couple of other 9020s around that need the same treatment, so the effort won’t go to waste.
Long ago, a wood-base countertop cheese slicer arrived with a tenuous connection between its screw-on knob / handle and the bolt securing the cutting wire. The problem seemed to be boogered bolt threads:
The knob screwed firmly onto a known-good 10-24 screw, not the M5 bolt I expected, so the slicer may be old enough to be Made In America. Ya never know around here.
However, the hex head is essential, because you must hold it while tightening the nut capturing the slicing wire. Not having a 10-24 or even 10-32 bolt in hand, I went full-frontal metric with an M5 bolt.
Even with a full face shield, I don’t like standing in the plane of an abrasive cutting tool, even a piddly Dremel disk, so the slot through the head isn’t the best work I’ve ever presented:
Indeed:
But it’s hereby defined to be Good Enough™ for the purpose.
As you might expect, I ran an M5×0.8 tap into the existing 10-24 knob thread, hand-turning the lathe chuck and lining up the tap wrench with the tailstock.
Drill out the slicer’s frame hole to clear the bolt, re-string wire through slot, tighten jam nut, add a locking nut on the other side, screw on the knob, and it’s All Good:
Ugly, but good.
I expect the re-wrapped wire will break in short order, because you just can’t re-bend steel wire with impunity. So far, so good.
My pre-trip checklist now includes “Duct Tape”, so, when the tiny screw holding my sunglasses together went spung and dropped the lens on the parking lot gravel, I was prepared:
I continued the mission in full-frontal Harry Potter mode.
Fortunately, it’s a captive screw and returned home with us. Back in the Basement Laboratory, with a Philips 00 screwdriver and threadlocker at hand, the repair was no big deal:
You’re looking at the screw head, believe it or not.
And, no, I’m not packing a Philips 00 screwdriver on our next trip.
As a followup to the DOT-01 battery status, I found the last of the Wasabi NP-BX1 batteries in a drawer where they’d sat unused for eight months.
Recharge and test to get the blue lines, with the red lines from the DOT-01 batteries:
The double blue line came from a second recharge of that battery, just to see if more electrons would help. Nope, it’s still dead.
The Wasabi battery with the highest capacity also has the weirdly rippled voltage trace and, when I extracted it from the test holder, came out disturbingly warm and all swoll up. This is A Bad Sign™, so it spent the next few hours chillin’ on the patio and now resides in the recycle box.
One of the wireless numeric keypads I’ve been using with the streaming radio players developed some intermittent key switch failures resisting all the usual blandishments. Eventually it hard-failed, but I was unwilling to scrap the tediously printed keycap labels:
Hard to believe, but I’ve been using the white keypad for plain old numeric entry with the keypad-less Kinesis Freestyle 2 keyboard.
I swapped the Frankenpad + receiver to the least-conspicuous streamer and, someday, I’ll update all the labels on all the keypads to match the current streams. Until then, the white keycaps shall remain in the same bag as the defunct black keypad, tucked into the Big Box o’ USB mice & suchlike.
