𞋴𝛂𝛋𝛆

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Joined 2 years ago
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Cake day: June 9th, 2023

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  • Yeah, I’m kinda volunteering for the mod part. In truth I think it would take the respective instance admin setting up such a thing specifically. Like create a throwaway or something so that the actual user is not propagated to other admin or the full activity pub feed being transported. The one instance admin would know and have the ability to filter or block, but that information would never escape the one server. As a mod I would be blind to actual potential bad actors and only filter at the liberal community and comments level. So basically a normal community that replaces the OP name with Anon, and never shares the real ID with anyone.


  • I keep seeing people go to the effort of creating a throwaway account to say or post stuff they want or need to externalize on the threadiverse. I’m willing to bet that for every person that goes to that much effort, there are likely somewhere between 10-100 people that lack an outlet and motivation to do the same. Greentext is just a mutual pretext on my part for genuinely caring about people under pressure right now and in need of an outlet in a way that is not really well supported by the fediverse or activity pub.

    We are small enough here that regular names and people can hold meaning in familiarity and memorable history. Kind words and social interaction anonymously from these may hold considerably more value and meaning within this social dynamic that is not afforded elsewhere.





  • Biology as a technology will be our only potential long term future. All we need to do right now is access one near Earth large m-type astroid that was a planetesimal core. That would likely yield more mineral wealth than humans have accessed in the entire Holocene. Scarcity drives the present world. Planetary gravitational differentiation is a mean bitch that left us to fight over the scraps left over by eons of surface collisions. We live on the planetary flux and light junk that floats to the surface. The core of any differentiated body is quite literally the limitless treasure at the center of the Earth. If such a body is accessed, that upends scarcity and therefore all of our economic value systems. However it unlocks the wealth and resources needed to build O’Neill cylinder size cislunar habitats. Those habitats then force development of closed loop biological systems. Heat dissipation becomes the primary constraint in such a place. It actually becomes a primary currency and therefore shifts cultural values significantly. The removal of anonymous exploitation of environmental wealth due to a closed loop system like an O’Neill cylinder will be the main catalyst that makes the present look as backwards and primitive as the Romans, Greeks, Egyptians, or Han Chinese of 2k+ years ago. We can build O’Neill cylinders up to 9.1 × 30 kilometers based on materials science of the 1970s. The main thing stopping us is access to resources and political will. A single m-type astroid with an Apollo program size effort is all it takes to enter a new epic that dwarfs the present.


  • I’m simply questioning my childish assumption that catastrophic mega events are relegated to the past. The assumption is based on the scopes of the existence of complex extant life and the relative calm of the present Holocene. I grew into the perception that mega events were of a bygone era because geologic time is not intuitive to children, and until recently I have not had the casual curiosity to expand my awareness and question said assumptions.

    The existence of protohumans up to the present seemed grounded in some underlying truth of ongoing stability that now seems totally at odds with geological reality and timescales. The question here is grasping at straws in a way; hoping that perhaps this connection is wrong as I realize the finite potential of complex life as it exists presently.

    I mean in all likelihood we have tens of millions of years and an ice age or two before a true mega event pushes life into much simpler forms from the immense pressure of planetary cataclysm. If we manage to master biology as an engineering field, we may escape such a planetary bound fate in the distant future, but as long as we are trapped in this planetary gravity prison, we are perpetually sentenced to death row by the judge of geologic time.

    In other words I’m realizing the full extent of geology as a study of the future where no event present is relegated to the past. My mind then races to questions of what it would be like and the building signs of eminent cataclysm. I do not mean this like the emotional hype doomsday psychosis nonsense in clickbait media or the discovery channel. I mean more like from a hard science fiction (extremely amateur hobbyist) writers perspective. Even if most of humanity migrates to cislunar space or elsewhere, there will likely be a large population present on the planet. How that plays out across generations and how diversity of life is valued becomes interesting to me under the premise of biology as a fully mastered engineering field.

    Of course it is mostly speculative within my interests and curiosities. Still I think there are a lot of people that share the assumption that the geologic past is not the future; that something fundamentally has changed; that we are masters of our own fate where we are the greatest and only risk to ourselves in perpetuity, perhaps only short of an astroid impact of sufficient magnitude.



  • 𞋴𝛂𝛋𝛆@lemmy.worldMto3DPrinting@lemmy.worldBambu Printers Discussion
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    7 days ago

    I have no skin in this, but VC is involved with Bambu, as I understand things. That never goes well for consumers. They backpedaled to slow down the path to closed garden exploitation, but took no steps to open source or sell a legitimate product that can be owned. The solution is unplug it from the internet cause we gonna do what we gonna do (fu fu)

    Build a Voron and own it for life. I know the excuses, but burning ownership-money, only to rent what someone else controls is mental. In the big picture, that is willingly selling your right to citizenship for neo feudalism as a slave to an overlord. It really is that simple. Normalizing that dystopia hurts everyone else too. But hey you do you. I’m happy for ya if that is your cup of tea.





  • Smooth prusa powder coated works great.

    Drying makes a gigantic difference. It only takes around an hour in the open before TPU changes significantly from any ambient moisture and become visible in the print.

    If you can control the moisture to a minor degree, you can alter the mechanical properties significantly. Once you hear popping, you’ll likely start blowing holes in prints, but there is a stage before this where the bubbles of gases are present but are not coalescing into the larger audible voids of escaping steam. You will see this on long prints using dried TPU filament left out in the open. There will be a much tougher start to the print that gradually degrades into a slightly softer and more flexible texture. It will likely turn slightly foam-like spongy rubbery soft for a section and then it will start popping and dropping walls with holes in the structure.

    If you write down the room temperature and humidity and note the time it takes to get to this moisture property, it becomes possible to alter the flexible properties or empirical hardness of a TPU to make it behave in off label ways. This is essentially creating your own rudimentary foaming or light weight filament. It works best for vase mode or other small single wall structures. I have used this based on intuition alone. I imagine with a bit of record keeping one could control the humidity of a box to do longer prints within this state of foaming softness. I don’t know of anyone using a humidifier like the ones for acoustic guitar cases or cigars in a filament box, but that would be an interesting thing to play with too.



  • You can just slap a dial gauge on the gantry and move the X/Y manually to see exactly what the deviation is. A decent second-hand dial gauge on eBay will run you $20 shipped.

    If you get into the weeds, there is not an accurate method of triggering any form of mechanical stop that involves touch or a hall effect probe. You must get into optics for real accuracy, but that is nonsense for the materials and scope of printing. You would need to eliminate many other variables like the filament accuracy and how backlash and step accuracy are eliminated as issues.

    As a former owner of an auto body shop with employees, most people do not know what clean is or how tooth is required. Like isopropyl alcohol has its place but is ultimately extremely weak at real cleaning problems. In automotive paint, silicone is a major problem. It primarily comes from tire dressing that makes them look slick black. The amount of effort it takes to remove that junk for automotive quality work is insane. Most chemicals just push the junk around but leaves or dilutes the issue often making it worse. One of the big tricks in automotive stuff is (to use a chemical cleaning step first but -) a few drops of dish soap in the wet sanding bucket. The light soap will keep the sand paper clean and working longer, but makes most work also cleaning work. Anyways, dish soap can be very effective. Acetone occasionally on a surface is also effective. Virgin lacquer thinner is the strongest common solvent but it can react with lots of stuff and you are unlikely to find true virgin solvent. The recycled stuff has a paint stripper component in it that will cause epic nightmares and reacts with almost all plastics. Acetone is much cleaner and consistent unless it is sold for junk like nail polish.

    The general rule of thumb is to assume a mechanical tooth adhesion is the primary form of bonding unless there is a catalyst involved (2k urethane/epoxy primers/clear). That rule can easily apply to 3d printing and bed adhesion. I see a lot of the same types of effects from different surfaces and filaments. In automotive paint, there are even special adhesion promoters like Bulldog for spraying plastic parts ahead of other finishes. I had other adhesion promotion tricks too, like a mist coating of clear coat. The main trick with all automotive paint adhesion is to know what grit or “tooth” each thing you’re spraying wants to grab onto and prep accordingly. So in 3d printing I use a similar approach with the general safe bet of sanding my smooth build plates to 600 grit. With sanding, do not start dirty, like you’re trying to embed junk into the surface. Start clean, then knock off the shine to a smooth and consistent matte finish on the entire surface. When it comes to sanding like this, edges and any anomalies are absolutely forbidden to sand. Never touch your edges until last when everything else is done. Edges are always thinnest and most vulnerable to causing issues especially for the inexperienced. You match them to the rest of the matte surface carefully at the end.

    Clean a smooth build plate with acetone like once or twice a year and then sand it to matte, clean that with dish soap, then alcohol with each print. That will completely eliminate contamination as a cause. If you have old skool clean glass with no coatings as a build plate, sanding is optional because you can use something like lacquer thinner or less effective acetone to get it absolutely clean.

    Perfect first layers are possible with enough fussing with the software. If you really want to level the bed with hardware, use a dial gauge clamped to the extruder. That will remove all of the averaging and inaccuracies from probing if it is a quality gauge that is smooth and not sticky. You would need to get into optics for true accuracy like with closed loop control systems that are an order of magnitude more expensive than 3d printers. 3d printers are precision machines with no accuracy. The 0,0 home location is always slightly different, but all measurements are based upon this location. This issue becomes relevant with IDEX and CNC. Going well beyond these – in optics accuracy requires a defraction grading and alignment of light wave patterns. I so want to get into that one to grind my own telescope mirrors. Typically accurate machines use a flag of metal sticking out somewhere at a known location and an optical encoder switch that gets interrupted without anything touching as this is typically the closest you’ll get to real accuracy down to the clock and instructions timing of the interrupt routine in the microcontroller.

    If you have v-roller wheels on extrusions, one other major potential issue is that extrusions have a relatively large twist tolerance component in their specification. It is extremely difficult to detect this kind of twist, but it is a major potential issue. It generally requires a high metrology grade granite surface block and parallel sticks to measure twist in a precision instrument’s linear bearings… as far as I understand it. I have seen such things being measured but have never done so myself.


  • Very cool. I was thinking about ways of making a potentiometer knob on an audio amp more visually interesting. The moire effect might be one to play around with.

    I don’t think I would trust this one in practice, but the effect is interesting. I found it far more necessary to learn the vernier scale with micrometers. It felt much more useful understanding the practical limitations and scope of when to use calipers versus a mic. While there are super accurate calipers, relatively cheap calipers and micrometers are far cheaper and easier for most people to access.

    When it comes to radius gauges I trust these more than any of the others I have tried:

    I know this kinda isn’t the point, but using it as an excuse to share – the fishing leader line to hold a set like this is key to making them super handy. Unfortunately I have only used micrometers on a few 3d printing projects. Those are more used within the machining realm.