dual_sport_dork 🐧🗡️

Progenitor of the Weird Knife Wednesday feature column. Is “column” the right word? Anyway, apparently I also coined the Very Specific Object nomenclature now sporadically used in the 3D printing community. Yeah, that was me. This must be how Cory Doctorow feels all the time these days.

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Joined 3 years ago
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Cake day: July 20th, 2023

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  • Note to others: Don’t do this unless you’ve verified that your particular LED already has the resistor built into it, which is how those work.

    Otherwise, hooking a bare LED up to DC voltage tends to eventually convert it to a smoke emitting diode, especially since LEDs have an inverse temperature/resistance relationship. The hotter it gets the lower its resistance becomes so the more current it draws so the hotter it gets so the lower its resistance becomes so the more current it… pop.



  • Every single established procedure we have at work which are there to prevent people from shooting themselves in the foot, which they instantly forget if they haven’t encountered whatever that situation is in the last, oh, three days or so. And then proceed directly to shooting themselves in the foot by making up their “own way” to handle whatever it was because “they didn’t know what to do,” which then turns out to be wrong 100% of the time. Which is why we have those procedures in the first place.






  • That is a dust cover. Behind that is a ball bearing assembly, which is probably not designed to be greased or serviced, only replaced.

    The dust cover is usually rubber, and you can pick it off using a toothpick or small plastic prybar. Resist the urge to use anything metal on it unless absolutely necessary since this might damage whatever is left of the rubber.

    Behind that you’ll see one of two things:

    A sealed bearing, which can’t be greased or serviced…

    …Or the cage of an open bearing which can be packed with grease.

    When I say packed, I do mean packed. That’s how open bearings work. Fill all of the available air space with grease, and if possible push out any of the old dirty grease in the process. You’ll probably want a rubber glove. For particularly annoying to access recessed bearings I use a drugstore oral syringe, i.e. with a wide nozzle and no needle, via filling it using a popsicle stick as a spoon. I use the red Mobil 1 synthetic grease for this type of thing. And, indeed, practically everything else as well such as motorcycle hub bearings, swingarm linkages, etc.

    If it’s a sealed bearing that’s trashed you’ll have to replace it which is done via knocking it out from the other side and tapping the new one back in with a hammer, preferably after sticking it in your freezer for an hour or so to shrink it first.







  • In theory, yes. But those usually have electronics in them in an attempt to save you from yourself. So it’s unlikely that the thing would fire when you wanted it to without being fooled into believing it was hooked up to a 12v battery in some way.

    You can get off brand motorcycle batteries online for like $20. The quality is irrelevant for this application, especially since you probably won’t be welding hundreds of battery tabs in a day. The point is that they can reliably deliver enough amperage to weld the tabs while having a low enough terminal voltage to be unlikely to deal either yourself or your cells a mischief.


  • I made my own out of a motorcycle battery (which I have lying around in abundance), a length of jumper cable, a starter relay off of I think a 50cc scooter with a random salvaged microswitch as the trigger, and two short lengths of sharpened 10 gauge Romex as the probes. It works a treat. I haven’t fried a single 18650 with it yet.

    I think my total net bill of materials was about $12, not including the junk I already had lying around, the majority of which was the relay.






  • How bizarre. I have noticed similar things in the past, in particular when lemmy.world was having federation difficulties (there was a pinned post about it a few days ago). Randomly posts of mine as well as others that were months old would show up interspersed with normal results when sorting posts by “new.” I wonder if this is a related bug.

    I think I fixed a typo in the Kalashnikov post the other day, though. I’ve been going over some of the oldies and cleaning things up now that they’re all linked on my website as well.