Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
The bucket contained all the water to start with, so with the icemaker and laser tube empty, all the water is back in the bucket. Getting all the bubbles out of the laser tube takes a while after the pump starts running, so I stuck a check valve on the laser output tube in the icemaker’s reservoir:
Silonn icemaker – inlet check valve
Which, after a few days, developed a slow leak, once again emptying the reservoir.
There being no way to dismantle the valve for analysis and cleaning, I just cut it apart:
Silonn icemaker – inlet check disassembly
Lo and behold, a small tangle of thin fibers had found its way into the valve:
Silonn icemaker – check valve debris
Which held the silicone disk ajar and let the water slowly leak backwards through the valve.
I have no idea where it might have come from, but a simple filter seems like a good idea. Given that the pump produces pretty nearly zero pressure, anything fancier than a coffee filter in a funnel would present too much back pressure.
Or, with three more valves in the bag, I can wait to see how long it takes for another tangle to arrive …
The mudflap on my front fender rides low enough to snag on obstacles and the most recent incident (about which more later) was a doozy, breaking the left strut ferrule and pulling the bracket off its double-sticky foam tape attachment. Fortunately, the repair kit now has plenty of duct tape.
While running some finger-joint test pieces, this happened:
Detached laser lens holder
The knurled ring just below the Tight→ label worked its way loose and released the lens holder tube collet, whereupon the whole affair fell out and dangled on the air hose & wires as the gantry continued to zigzag along the finger pattern.
As is my custom, I was watching the proceedings and managed to poke the controller’s STOP button, which was a mistake. What I should have done was slap the EMERGENCY STOP mushroom switch, because the STOP button just tells the controller to cancel the current action and return to the home position, which resulted in dragging the lens holder across the plywood and platform.
The more typical laser cutter failure seems to be having the controller execute the Halt and Catch Fire instruction, resulting in at least a ruined workpiece, sometimes a ruined laser, and occasionally a serious conflagration.
Lesson learned: practice slapping the Big Red Switch every now and then.
Although the blurb for the Epson ET-3830 All-In-One scanner / printer says “up to 2 years of ink in the box”, the black ink hit the bottom line of the tank near the end of August:
Being that type of guy, I keep track of ink vs. time:
Epson ET-3830 – ink status
In round numbers, it looks like we use nearly all of a 127 ml bottle of black ink and a bit more than half of an 70 ml bottle of color ink every eight months.
I find it much easier to read long articles and tech documents while slumped in the Power Chair than to scroll through them on big or little screens, so we go through much more ink and paper than most folks.
An old brass hose nozzle emerged from my garden hydraulics toolbox when a much newer plastic nozzle failed. Unfortunately, this one leaked a bit too much to serve as a replacement, so I grabbed it in the vise while pondering how to disassemble it:
Champion brass hose nozzle – disassembly
It turns out the knurled ring is threaded into the nozzle and, even at this late date, responds well to gentle persuasion with a Vise-Grip:
Champion brass hose nozzle – parts
The washer is a lost cause, but I managed to find an O-ring that fit perfectly in the space available. Clearing some crud around the nozzle hole and buffing up the matching conical section improved its sealing ability, so I’ll call it a win.
The word ITALY stamped opposite CHAMPION suggests this thing might be as old as I am; it’s been a while since either brass or Italy was competitive in the world of cheap manufactured goods.
I set up my pobox.com account set up with two-factor authentication through my Yubikey, so logging in requires my user ID, password, and a Time-based One-time Password generated through the Yubikey Authenticator program. A few weeks ago, pobox occasionally rejected the TOTP and it eventually became a hard failure. Oddly, other sites I’ve set up with TOTP 2FA continued to work fine.
My initial trouble report:
The last couple of times I’ve tried to sign in, the usual TOTP copy-n-paste from my Yubikey authenticator has failed.
Up to that point, it worked flawlessly.
Manually typing the TOTP also fails.
I have reset my (complex!) password to no avail; I use Firefox’s password manager to fill it in.
I do have a set of lockout codes, but they’re a solution to a different problem.
Given the constant updates to Firefox (102.0.3), it’s almost certain the hole is in my end of the boat. I have disabled all the usual ad blocking for pobox.com, although there may be other domains I’ve overlooked.
Other than that, my email seems to be working just fine …
Any suggestions on how to proceed? (Obviously, I’m not going to be able to sign on to look at the ticket.)
Thanks …
This is the fastest I’ve ever reached Tier 2:
We’re happy to help you with this. I’ve escalated your ticket to our Tier 2 agents, as they are best suited to assist with this issue.
There is nothing like a good new problem to take your mind off all your old problems:
I’ve had a chat with our Tier 2 agents about this and they’ve suggested I escalate it to our developers to have a look at.
Somewhat later:
I am afraid to say that our developers were unable to find any clear reason as to why your Yubikey failed.
Yubikey devices verify by connecting with Yubikey’s server, and it is possible that this connection failed.
Can you please try using the Yubikey again to see if the issue is still occurring?
If it’s still failing, can you please try adding a new Yubikey device to see if it works?
Of course, the problem didn’t magically Go Away, but I did more experimentation and figured out where the hole was in my end of the boat:
Ah-HA! It’s a PEBKAC error!
For unknown reasons, this PC was not set for automatic NTP time updates(*). Its time had drifted (presumably since I installed it back in June 2021) and was now 58 seconds behind real time, exceeding pobox’s tolerance.
Other websites apparently allow a few more seconds of slop before disallowing a TOTP, so I had not yet run afoul of their limit.
Some lesser-used sites threw me out, however, but I had not looked beyond the most common sites.
The default TOTP interval is 30 seconds, so perhaps pobox allows only ±1 interval and the other sites allow ±2? Frankly, I think pobox has it right: everybody else prioritizes customer sat over security.
Got the clock set correctly and, gosh, TOTP works fine.
Mark it solved, but definitely add “Soooo, is your PC’s clock set for automatic updates?” to the debugging protocol.
Thanks …
(*) I’ve installed all of the boxen here and would not ever have picked “Yeah, sure, I want to dink with the clock.”
How you make sure time synchronization is enabled goes like this:
$ systemctl status systemd-timesyncd.service
● systemd-timesyncd.service - Network Time Synchronization
Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled; preset: enabled)
Active: active (running) since Thu 2022-08-25 06:49:31 EDT; 10h ago
Docs: man:systemd-timesyncd.service(8)
Main PID: 355 (systemd-timesyn)
Status: "Contacted time server 23.157.160.168:123 (2.manjaro.pool.ntp.org)."
Tasks: 2 (limit: 19063)
Memory: 2.2M
CPU: 188ms
CGroup: /system.slice/systemd-timesyncd.service
└─355 /usr/lib/systemd/systemd-timesyncd
Aug 25 06:49:31 shiitake systemd[1]: Starting Network Time Synchronization...
Aug 25 06:49:31 shiitake systemd[1]: Started Network Time Synchronization.
Aug 25 06:50:12 shiitake systemd-timesyncd[355]: Timed out waiting for reply from 162.159.200.123:123 (2.manjaro.pool.ntp.org).
Aug 25 06:50:12 shiitake systemd-timesyncd[355]: Contacted time server 23.157.160.168:123 (2.manjaro.pool.ntp.org).
Aug 25 06:50:12 shiitake systemd-timesyncd[355]: Initial clock synchronization to Thu 2022-08-25 06:50:12.850444 EDT.
If it’s enabled and running, then it’s all good.
Whereupon all my TOTP passwords began working again.
I checked two other Manjaro systems: one had auto updates enabled, one didn’t. I have no explanation.
The Smell of Molten Projects in the Morning 