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Cake day: March 15th, 2024

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  • Not really, although that was clearly a popular impression created by the 1980s Right Stuff movie.

    Both the US and USSR had the A4/V-2 rocket and both the US Redstone and USSR R-11/SS-1 “Scud” were grown-up and bug-fixed versions thereof.

    The US kept the Operation Paperclip folks going throughout the program, leading to Von Braun’s team designing the Saturn V rocket, even though the Redstone Arsenal / Marshall Space Flight Center folks didn’t design some of the other rockets.

    The USSR kept their Germans under a tight leash and every time they designed a rocket, they’d have the Soviet team design the same thing, they’d compare, and then after a few years, they sent back their Germans to live in obscurity because the Soviet team had gotten good enough.

    Thus big rockets ended up being a German ex-Nazi party member, Von Braun and his Saturn V vs a Ukranian, Korolev and his N-1.

    Thus, an astonishing number of rockets are based off of the A-4 design, many of them with the Scud as the middle step. And neither America nor Russia gets to really take credit for their chief designer, where obviously both men were mostly acting to provide structure to the giant armies of engineers who did the actual work (but doing it well, the USSR program really screwed things up after Korolev passed away). But there was a bunch of really neat bits of rocket science that the USSR did in the 70s-80s that was well above where the US was specifically because while Korolev was Von Braun’s generation, most of the newly taught Soviet scientists were not. Where, again, the real problem was that Korolev didn’t have any good successor leaders and the USSR was in a state of stagflation.

    And you can say many things about the USSR space program, but they were significantly less “nazi” than the US program.




  • This can get very expensive very fast. Okay, so 20 years ago concert photographers shot on 800 film pushed to 1600 or 3200 and shot on f/2.8 constant lenses, sometimes f/1.8 primes and then walked naked through the snow to milk the developer rodent for the C-41 chemicals. And now 6400 looks pretty darn good on a small sensor even. But it just means that concert photographers want more more more more!

    200mm at f/5.6 is going to be really really hard to work with. Or whatever the Sony is at the same zoom setting.

    I shoot a lot of smaller dance and circus shows and I use the Olympus 12-40mm f/2.8 Pro, which is about 24-80 in full-frame terms. If I wanted to do larger arenas where I’d be farther away … I’d probably get the longer brother of my 12-40mm f/2.8 Pro and put it on a second body or just swap lenses regularly. If you are going to be fairly far from the stage in an arena, I’d probably suggest you get something that’s got a shorter zoom range but is faster and then use even just the kit lens for the wide shots because the longer the lens, the more problems you will have both with your hands shaking the lens and the subject moving.



  • You can always mock some stuff up and try it out in PrusaSlicer to see how long it thinks it’ll take?

    Wall thickness potentially depends on the size of the object? I guess 2mm would the the starting point, fill one with soil, see how sturdy it feels. Complexity for 3D printing is “free”, kinda. A lot of the best container designs incorporate ribs to strengthen them without using up too much material. Given that the joins are the weak part, you’d potentially want that a lot thicker.

    You also want to look at “vase mode”. Some of the fastest printing objects you can get on a 3D printer are where you design around the constraints of vase mode and then you can use a fat nozzle with thick layers to print really fast.

    You can always print plumbing instead of using PVC pipes? I’ve definitely seen self-watering pots such that they just have a pipe incorporated into the design such that it just sticks up along the corner. So, worse case, each module has a watering port. If you want to get fancy, you could make a manifold such that a single pipe sticks up in the middle and fills 4 reservoirs, although the fancier the plumbing the more likely you are to have one of them get dried out faster unless your filling routine tops them off.


  • Yeah, see if you know Python, then OpenSCAD is not a hard jump? One of the reasons why I really like OpenSCAD is that libraries like BOSL2 have parametric joiners and snaps and stuff. And you could totally write modifiers for FreeCAD or Blender to do it, sure, but it’s a lot less trouble to get it done with OpenSCAD. This way your end-result would let you input the size of the bed and it would figure out how many sections it needs, etc.

    Lesee… 120x40x40cm is a lot of plastic to print, even with a single printer running all day all night.

    What I’d suggest is that you make the wooden outside for the 120x40x40cm shelf and make 20cm x 20cm x 40cm units. At which point you can make bigger multi-part modules. It might actually make sense to keep the cups separate because you could adjust the holes and stuff based on the plant’s needs. Whereas the reservoir section is going to be happiest as a single tub. But the important part is that if you are a few modules short, just add a spacer for this season. And it gives you more time to experiment on the tub and allows you to swap that out mid-season.


  • This is pretty darn ambitious for a starter project. I say this as someone who is trying to get some fancy new 3D printable tomato cages going before the plants get tall and dangerous and I’ve been doing this for a while.

    So you really probably want to de-complicate this, either by only making planters that are sized for the printer or finding a existing planter that’s the right size but not self-watering and designing just the self-watering part. You’ll probably learn a lot about the right way to do one this year and then next year you can attack the next generation of the planters.

    The problem with printing in pieces is that you are going to have to make sure that the joints are strong enough for the weight of the soil. This is why using a ready-made outer container might help. In the same way, what you really want is something finger-ish or jigsaw-ish so that the pieces align themselves more easily and interlock.

    You will probably want a fatter nozzle, otherwise this is going to take forever to print.

    PETG seems to have worked fairly well for me for outdoor stuff? Coating or paint or whatnot is handy. You might want to look at the epoxy family? If you can print on the balcony, you might consider ASA which is totally fine for outdoor use with no paint.

    FreeCAD is a bit of a learning curve? The thing that FreeCAD would make easier is a parametric model, where you say that you want a 400 x 400 x 300 planter. Except that if you are really serious about making large self-watering planters that are parametric, you are going to end up wanting to write code to make it all happen, which either means the Python in FreeCAD, the Python in Blender, or maybe just use OpenSCAD.

    One avenue, which is also too big of an ask for this season, is making a multi-part model to cast the large pieces in concrete.

    Another avenue would be to just design around the outside being wood and the 3D printed parts being brackets and jigs and connectors and the self-watering bits.


  • There really aren’t any simple counterfactual historical arguments to be made.

    I have a fairly strong feeling that, of the various shuttle variants studied, the majority of them would have at least been vulnerable to a Columbia level disaster.

    Plus, the shuttle was very much overweight and there were a lot of nasty compromises there, so I kinda wonder that if they’d gone for broke with the two stage reusable designs that they’d have ended up just getting cancelled because the more reusable things are, the colder the equations. So you can’t even really treat the earlier proposals as something that might have worked out better. There are things that no amount of money can make work. Like faster-than-light travel without a fundamental reassessment of physics.

    And then a lot of the things in the late-70s-early-80s vision wouldn’t have worked out. There was a giant Microwave Radiometer Satellite project that they were cooking on with a giant antenna with a radius of 1150m. Eventually that survey was completed with a much smaller synthetic aperture radio that sat in the shuttle’s cargo bay and today there are lots of tiny SAR survey satellites.

    There was another giant geosynchronous dish antenna that was supposed to be a single cell phone satellite for all of the continental US. That was overall a bad idea, Iridium did a better version with less lag in lower orbits, and now we’ve got Starlink and some new competitors coming online and, overall, cell coverage is actually pretty great with conventional towers.

    Then again, here’s this paper from 1973. See, the shuttle ended up with a reusable second stage the conventional wisdom was that the second stage is always the expensive one so therefore make that reusable and the first stage can basically be a steel pipe with propellant poured into it and everything’s fine and the bulk doesn’t matter. Thus, only a madman would reuse the first stage. Which is why they were proposing putting parachutes on the Redstone rockets that Mercury used for reuse but never bothered. But, see, they were going to build this two-stage reusable rocket but wanted to preserve the option of launching large bulky cargo… yeah.




  • Yah, I think that using LLM’s while ignoring all of the externalities involved is … everything Solarpunk is in opposition to? There’s a rejection of the idea that this thing that looks bad now might pay off down the road because mumble mumble mumble progress.

    Take a bicycle. A bicycle allows a person to transport themselves using overall less energy than walking. You can even work through the externalities and maybe make bamboo bikes and stuff and maybe try to carefully optimize the externalities better. But it looks pretty darn good at the start, gets better.

    That’s not LLMs.


  • IoT devices are, to be quite honest, a shitshow. Where your Sovol counts as such.

    Either the device needs to call upstream to get updates or it’s going to ship with a security bug that can be exploited. Or, in may cases, it’ll have an unpatched security vulnerability and it’ll call upstream to get updates.

    It costs money to keep the necessary cloud infrastructure in place, both in terms of hosting costs as well as devops time. Either they will eventually need to brick the device, leave it unpatched forever, charge you some maintenance fee, go bankrupt, or fund the whole thing by selling your data.

    It’s not hard to write a bot that would scan for signs of a Sovol printer, try the default SSH password, and do nefarious things. And people are generally really bad about the default SSH password regardless.

    There’s not really a good answer here for IoT devices. There’s not even a really great answer for home brew IoT devices with the thing where Home Assistant’s reverse-tunnel service had a nasty vulnerability that let you remote HA instances.

    Aaand… IPv6 is great. But unfortunately the way things are now means that giving everything on your network a publicly routable IPv6 address is a very bad idea.

    Klipper provides a lot of protections but all of that hinges on the microcontroller, so presumably an attacker can upload a substitute firmware using the update mechanism that would go full send on the heaters, which has the potential to actually melt some things.

    The problem is that if you want Klipper, you need a full Linux. This is not actually a problem for the Klipper devs, mind you, because they wrote a cool tool for people comfortable modding their printers and only BTT and Obico sponsor Klipper. This was a lot less of a problem when we were talking about Marlin printers. Except that if people weren’t using Klipper, it’s just too damn easy to write a two-piece controller software in the same fashion of Klipper and get the expediency of writing code in Linux instead of in an os-less microcontroller.

    tl;dr: there is no safe way to buy a printer with klipper on it, it just looks like it works right now.



  • The hard-to-solve problem with the news is that reporting on suicides causes suicide (as in: more people commit suicide, not just people who were on the ledge decided to go) yet people also want to know things.

    I’m unclear if the usual disclaimers added to the article actually help or just are the only sounds-like-it-might-help thing that comes to mind so at least the publisher can feel better about the added deaths that, statistically speaking, they might be causing. I just remember it being covered in one of my college gened classes and the way it was presented was that everybody threw up their hands in frustration and gave up.

    An acquaintance who screwed up her leg really bad and went through a whole process of getting bolted back together et al decided that she wasn’t going to tell people what happened. Because everybody always asks “how’d you do it?” as if it was some curse that she had personally triggered that they could avoid. And I thought about how the first question in my mind was “how’d you do it?” and I guess it made me think about the inanity of making sure to check for flying herring while traveling backwards hanging out the window of a train going between Albuquerque and Phoenix after having signed up for a triple indemnity life insurance plan… or something like that.

    The only exception, of course, is you are doing something that the news orgs consider “wrong” like doing drugs or being certain categories of mentally ill or riding a bicycle for transportation.


  • I had a booth about this at the Bay Area Maker Faire lately.

    If we’re all printing the same object on our 3D printers, it’s proooobably a lot less trouble to just have someone injection mold it and save us all the trouble. 3D printers are really great for one-offs and mass-customization and things like that. Aaaaaand, I feel like it’s kind of an under-appreciated problem in 3D printing. Because, yeah, CAD is hard and we’re never going to reach a world where every 3D printer owner is very very comfortable with CAD, and so it should be more of a concrete goal for the 3D printing community to make sure that we’re focusing on this problem. It’s important that every 3D printer owner can do at least some amount of tweaking and customizing, otherwise we’re failing as a community.

    Now, I don’t Tinkshame. I spent a lot of time learning Blender, FreeCAD, and OpenSCAD to prove Naomi Wu’s assertion that we should all just get over ourselves and use TinkerCAD. The only real problem with it is that it’s not really free, it’s “free at the pleasure of AutoDesk” where they could raise the “Mission Accomplished” banner at some point and turn it off. And there’s not really an open source version of it for roughly the same reason that random thingiverse models are always kinda halfassed and bad. Doing a good TinkerCAD-but-actually-free-by-some-definition is actual work to get everything right and polished and documented and bug-free and nobody really wants to pay for it.

    Also, maybe I am pedantic and obsessive, but I don’t really like screwing around too heavily with models in a slicer, so I’d rather they take some of the magical code in the OrcaSlicer/PrusaSlicer/SuperSlicer tree and actually organize it into something that could be TinkerCAD-esque?

    Anyway, the core of the talk of my booth was systems and libraries of 3D printable objects. So, for example, there’s the Honeycomb Storage Wall system and some of us have been writing some neat lil OpenSCAD libraries and models for it (and another group of people have been doing similar things in Fusion) where you can make a parametric model so you can measure your flashlight and print a cute 40mm holder for it based on the measurement without having to model things from scratch and it’ll click into the HSW wall and it’s fine unless you are married to someone who has ommetaphobia and then you need to make sure that the honeycomb is the same color as the wall. And the same is true for Gridfinity, just you can put that in the drawer.

    And there’s also a lot of parametric models. I’m not sure what you are looking to print, but there’s a decent selection of people who have done stuff in Fusion or FreeCAD or OpenSCAD where you can download the model and change the parameters to get it a lot closer to what you want without going through all of the drama of making it all over again.

    I love using OpenSCAD. I’ve got a buncha years of experience using various 3D modelling tools at various times and so I can use Blender or FreeCAD quite well actually, but in the end, I do a lot of functional bits and it’s so darn easy to just write some code because, actually, I’ve been working as a professional software engineer for quite some time.

    So… dono, it depends on your aspirations? There were a good number of Gridfinity-like systems that were around before Gridfinity came out and they were … ok, but not great, but then Gridfinity came along and did a boxy-box system just like was already there but with some interesting tweaks and making it more amenable to real customization and suddenly everybody went gonzo over Gridfinity in particular. So you might not be just making a thing that exists in a dozen forms better if you borrow an idea and make your version of it.

    Also, I learned 3D modelling tools mumble mumble years ago in a failed attempt and/or dodged-bullet because I’d wanted to do games or special effects as a kid. The software I learned on is long gone, but it turns out that once you are thinking about things, it tends to stick? Which means that I learned pottery while visualizing the objects I was making on the wheel as if they were in the CAD window of my mind, got good at photographic lighting based on what I’d observed in the 3D program, and then transitioned back to CAD because I wanted to make things, so it’s kinda one of those things where you probably won’t waste the time spent.

    tl;dr: I learned OpenSCAD, FreeCAD, and Blender to prove that Naomi Wu is right and we should all get over ourselves and use TinkerCAD and … she’s still probably right, LOL.





  • A few years ago now I was thinking that it was about time for me to upgrade my desktop (with a case that dates back to 2000 or so, I guess they call them “sleepers” these days?) because some of my usual computer things were taking too long.

    And I realized that Intel was selling the 12th generation of the Core at that point, which means the next one was a 13th generation and I dono, I’m not superstitious but I figured if anything went wrong I’d feel pretty darn silly. So I pulled the trigger and got a 12th gen core processor and motherboard and a few other bits.

    This is quite amusing in retrospect.