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Joined 1 year ago
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Cake day: June 23rd, 2023

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  • So where do you put the rest of your helices on a cylinder or cone, in 2D? In Flatland a screw or bolt becomes a circle with a short hair. The whole point of “leftie loosy” is to try to help with reality as we perceive it.

    Try it the next time you are underneath a car wielding a socket spanner with a taped on extension thingie that you jury rigged whilst trying to shift a hex nut at 45 degrees to reality that you cannot see, with oil dripping in your eye. Obviously the oil is a mix of the 30 year old native stuff loosened up with the WD40 that might break the rust lock.

    I suggest you do think abut things in 3D and don’t forget the other dimension (time). That WD40 needs time to break the rust lock.

    “Leftie loosy” isn’t for keyboard worriers - its for engineers and technicians, plumbers, and the rest and obviously for DiYers.

    When you are knackered and pissed off and you need to shift a fucking nut or bolt or whatever, you need incantations to get you back on track.


  • Apple: User - you are holding it wrong!

    The spanner is always at 12 o’clock. Either turn yourself or the spanner or your point of view to make it so and then the rule holds. The last option require imagination.

    Take the piss after you have tried to thread a nut on a bolt that you cannot see and tightening it is towards you, at an angle. The nut has to cross a hack sawed thread and will try to cross thread 75% of the time unless the moon is in Venus.




  • They are not a circle unless you have some really odd bolts or screws! I suppose a bolt looks like a circle in “Flatland” but we live in 3D space with time as a fourth dimension that we can directly perceive.

    A screw or bolt and the rest are, roughly speaking, a cylinder with a helical thread on it. They also have a “head” or similar which acts a stopper. You can model all of them as a bolt. We use a spanner, wrench, fingers, screw drivers, drill drivers, scissors, whatever to do the tightening or loosening. You can model all those tools as a spanner (wrench). We need some final mental contortions to make this slightly rigorous: The spanner (wrench) is always considered as being at 12:00 on an imaginary clock and we have to assume that our bolt moves away from us for “tighten” and towards us for “loosen” and I suppose we should also require that we are looking at the “face” of the notional clock and not its obverse!

    Now it should be obvious how the rule works. Turn the spanner to the right and you tighten the bolt, turn it to the left and you loosen it.

    OK that lot is not very helpful when you are under a sink or in a roofing void performing strange contortions. Try holding up one of your hands and pretend you are holding a bolt or the head of a screw. Clockwise turns will tighten and anti clockwise will loosen. You might use “leftie loosey …” to bootstrap: “clockwise tighten”. It becomes even more interesting when you are trying to work out which way to turn a bolt or whatever when you can only feel it and when tightening actually moves it towards you.

    Think about a bolt running through a wheel with the head towards us, say on a very simplified bicycle. Move the bike to the right, and hence the wheels turn clockwise. Friction should cause the bolt to tighten. If you change the design and put the bolt in on the other side and now forwards for the bike is to the left then you will loosen the bolt and that will be dangerous. Now change the design to a bolt with a nut and washers etc and it rapidly gets complicated!

    Also, please note that some bolts have reverse threads to the norm. On a garden strimmer the tightening knob that holds the spool on is often a reverse threaded bolt. That’s for similar reasons to the bicycle wheel thing I mentioned earlier.

    I’ve just spent ages and a lot of words to try and persuade you that this has bugger all to do with autism. I think that your error was really to do with not thinking too deeply about the real issue and focusing on the wrong thing. We all do that, extremely often, regardless of where we are on the spectrum.

    I hope that you see that considerations with regarding helical threads on a cylinder or a tapering cone (but not circles) can be quite complicated and that’s why sometimes we all need some silly rules to get us through the every day ordeal of dealing with them.

    Now, would you like a chat about circles … 8)



  • SO: Next door have got their lights up, why haven’t we? Me: (Enable NodeRed flows for gutter and pergola light strings that switches them on at dusk and off late evening) Right, that’s the missus pacified for a week or so. I should probably get BigTimer to sort that out itself.

    Employee: I’ve got all the printers for monitored using an auto entries card. (Good skills) Me: (Installs an addon that can use VoIP to do text to speech to a phone) We warn off the customer and now they get a phone call from “things” that tells them what consumables to buy and also sends an email.

    When I finally get around to sorting out my glasses so I can see what my soldering iron is up to, I’ll get many more gadgets installed. My computer room at work needs a tiny ESP8266 and four 1 wire Dallas SC temperature sensors, a bit of vero board, a resistor, power and probably a buck convertor and a case, which I’ll print.

    I adore HA.



  • I only use Reolinks these days. RLC-410 - some dome and some bullet. Cheap and easy to setup. I’m a long term Zoneminder user which I get to watch the low res stream and record on the high res stream. My ZM is a VM on VMware with a cheap Nvidia GPU passed through for CUDA. This still works: https://wiki.zoneminder.com/GPU_passthrough_in_VMWare but I should probably bring the wiki page up to date.

    I have a Reolink door bell too - I went for the PoE one. It’s a lot better than my old Doorbird but not as sturdy. The door bird could drive a chime too which was nice. The Reo can’t but it is a PoE powered unit with a UPS backing the switch. That’s pretty resilient.

    They never get to see the internet. I fiddle DNS so that pool.ntp.com points at my ntp daemons but I run an IT company so that might be a bit excessive for most! I have three Pis with GPS hats and antennae.

    As you say, they are well supported by HA too. If you have a Coral and Frigate then you have lots of options. Just keep them away from the internet if you are concerned about who is looking through them apart from you.