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@ j4k3 @lemmy.world

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224
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1943
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3 yr. ago

  • It is just a cleanliness standard. It is not required. I spent a decade in the details of automotive paint. I only covered the surface basics for paint. What I call clean for paint is an order of magnitude more dirty than a surgeon, and they are orders of magnitude more dirty than a silicon chip foundry. When it comes to making plastic stick and look pretty, an automotive painter might be helpful for framing the scope of what is possible. All I can tell you is I have a Prusa and never have these problems, so I explained my experience and methodology as to why I do as I said. Again, sorry this upsets you.

  • I have not had problems with glass or PEI. Your other comments indicate you tried ABS. That will never work without an enclosure, and even then, it will not work particularly well on any Cartesian machine. Sorry that illustrative examples and abstractive reasoning are offensive to you.

  • It can coat the inside of the drier. Use Bounty paper towels as a control when in question. Bounty are often used in automotive paint shops for a few reasons, but they are trustworthy for composition. If the two plies are separated, they make a good strain filter. That is the primary reason they are used. They also tend to be lower lint though not perfect. A tack cloth is used in the booth with controlled filtered air flow either across or down draft, so it is not a concern for perfect paint.

    One of the tricks of automotive painting is to add a couple of drops of Palmolive dish soap to the water bucket used with wet sanding. It makes 3M Imperial Wet/Dry sandpaper last several times longer and acts as a mild degreaser the whole time. Any residue is cleaned in the booth stage using a special Wax and Grease Remover solvent that is the least reactive of the painting solvents. While this solvent is used extensively, still the fact that Palmolive dish soap can be used at all indicates how it is clean, consistent, and chemically irrelevant. Automotive paint reacts with many chemicals but specifically silicon is the worst problem. It causes fisheyes aka little divot like holes to form in the clearcoat. In most situations involving contamination and adhesion, silicon is the main issue that will be very persistent. It is so bad in automotive paint that in the worst cases, we turn to adding an actual silicon solution into the 2k clearcoat and trying to guess what concentration will match the problem area to level it. Otherwise, the entire job must be stripped to the raw surface and start over. Silicon issues only show up in the final wet clearcoat layer shortly after it is sprayed and leveled.

    The reason why I have written all of this is to illustrate this point: the silicon is essentially floating on every underlying layer. The solvent has wet the area and the silicon just floats to the top of some filler, 2k primer, sealer, top coat color and when it gets to the clearcoat it blows a hole through it. There are two solutions. Use a two part epoxy primer that is a pain in the ass to sand, or clean the the raw surface with lacquer thinner or virgin acetone. In automotive paint, those two solvents are dangerous for causing a ton of other contamination and reactions issues. However, these are the only solvents that will take off silicon without diluting it and making the problem worse. Alcohol is a joke with no place in the automotive paint world when I was painting. I got out before water based stuff ruined the industry by making refinishing exponentially more expensive. That is only the color coat and some primers, so there may be alcohol used in some way in these, but it will not involve cleaning. Tire shine is the main source of silicon issues in automotive paint.

    I have the empirical experience to know what I am looking at with cleaning and solvents. Alcohol is okay for minor issues, but think of it as constantly diluting and wiping the problem across the whole surface. Eventually, just use some virgin acetone to actually clean the thing properly. Paint is just plastic too. Each type requires a different type of tooth to mechanically bond to. With printing, I use 600 grit to lightly knock the shine off of the print plate surface. I go lighter on the textured sheet, but I only use the textured sheet with PETG because it is the only one that takes the textured pattern completely without showing layer lines. I print weekly on average, and use acetone and sandpaper around once a year. When I use glue stick, I clean the plate with dish soap after. I use alcohol in between. You will need an enclosure for ASA, ABS, and any larger PC prints regardless of the sheet or glue. Two IKEA Lack tables with legs stacked using double sided screws, then a clear shower curtain liner, and some tack nails does the job for under $50.

    I would never use towels from any drier that has ever had fabric softener used in it for automotive paint. That is a contamination nightmare for me.

  • It would have been more fun to paint cars if someone named the mixing colors like this. Yellow is actually quite rare in automotive mixing systems. You never see yellow cars. There are many you might mistake as actual yellow, but nearly all are a trick. There are usually 2 yellows that are used for tinting, mostly with whites. The primary black in automotive paint is actually yellow based. A tiny amount of black with a fine metallic is how most champagne colored cars are formulated.

  • Stump. I was a tree, but now a dump.

  • We need DNS filtering to work on outgoing packages by default, and to make whitelist DNS stupid simple to implement for any parent and child processes. It should be as simple as launching with the command, including a preconfigured whitelist, and a pop-up message for "approve, deny, prepend to list." System wide and incoming packet filtering is insufficient for the modern world.

  • llama.cpp is at the core of almost all offline, open weights models. The server it creates is Open AI API compatible. Oobabooga Textgen WebUI is more user GUI oriented but based on llama.cpp. Oobabooga has the setup for loading models with a split workload between the CPU and GPU which makes larger gguf quantized models possible to run. Llama.cpp, has this feature, Oobabooga implements it. The model loading settings and softmax sampling settings take some trial and error to dial in well. It helps if you have a way of monitoring GPU memory usage in real time. Like I use a script that appends my terminal window title bar with GPU memory usage until inference time.

    Ollama is another common project people use for offline open weights models, and it also runs on top of llama.cpp. It is a lot easier to get started in some instances and several projects use Ollama as a baseline for "Hello World!" type stuff. It has pretty good model loading and softmax settings without any fuss, but it does this at the expense of only running on GPU or CPU but never both in a split workload. This may seem great at first, but if you never experience running much larger quantized models in the 30B-140B range, you are unlikely to have success or a positive experience overall. The much smaller models in the 4B-14B range are all that are likely to run fast enough on your hardware AND completely load in your GPU memory if you only have 8GB-24GB. Most of the newer models are actually Mixture of Experts architectures. This means it is like loading ~7 models initially, but then only inferencing two of them at any one time. All you need is the system memory or the Deepspeed package (uses disk drive for excess space required) to load these larger models. Larger quantized models are much much smarter and more capable. You also need llama.cpp if you want to use function calling for agentic behaviors. Look into the agentic API and pull history in this area of llama.cpp before selecting what models to test in depth.

    Huggingface is the goto website for sharing and sourcing models. That is heavily integrated with GitHub, so it is probably as toxic long term, but I do not know of a real FOSS alternative for that one. Hosting models is massive I/O for a server.

  • tendentious milieu, or mircomilieu

  • Anyways, in my science fiction universe, I built it on the premise that biology is an engineering corpus, that biology is the ultimate final technology, and it eventually becomes like programming with Python, but many many orders of magnitude more complex. It is fun playing with ginkgo trees used for official structures; temperamental to work with but near infinite in age. Wall surfaces are grown of chitin. Most structures and furniture are grown from the Banyan tree. There is no industrial technology on the living level of the O'Neill cylinders. Culture has shifted to custodians of resources on stellar time scales. The complex human social hierarchy is shifted to skills, guilds, reputation, and accolades. The primary currency of exchange is a heat dissipation allowance. The lack of anonymity in exploiting natural resources, and the resultant heat, render accumulated wealth hierarchies obsolete.

    I think my biggest gamble is that there are sufficient incompatibilities and complexity that prevent major modifications to most species. The biggest biological achievement is the synthesis of a deterministic biological computer based loosely on the human brain. That innovation marks the end of the stone age of silicon, several centuries before my stories take place. I play in the first expansion of life outside of the Sol system using generation ships and one way travel. Wild Earth is only inhabited by a few indigenous groups. Most humans live in CisLunar O'Neill cylinders.

    All it takes is one m-type astroid. Any such differentiated planetesimal core contains more rare mineral wealth than all of what humans have accessed in the Holocene. If anyone gains access to this, to more wealth than all that Earth's differentiated scarcity has ever given us through the few impact remnants on the planetary surface dross, then we have the catalyst that produces the infrastructure and we head to space in mass within a century. The need to create fully cyclical terrarium worlds without waste drives the research and push to explore biology. Each holdout technology without a biologic solution weighs more heavily as more and more are dropped.

    I've been exploring how a volcanic traps like scenario builds up. I have also been working through ways to claim that those that modify their own genetics substantially have never managed to reproduce for more than 10 generations, and the problems that result are horrendous for the more generations that persist. Genetic modifications become the tin foil hat dogma tribalism fodder.

    No aliens, no FTL travel. There are kilometers scale self replicating drones that handle the required resource acquisition, any necessary industrial processes, and enable maintenance of habitats on the scale of stellar lifetimes. Interstellar travel is a major gamble where around half do not succeed. Indeed, while the generation ship is built with many of the larger structural components of the first O'Neill cylinder to be constructed at the destination, the small population will collapse and become sterile unless they get the first cylinders spinning within a few generations. The hub of the main habitat is the generation ship, which is spun to a twelfth of standard gravity.

    It is all possible because of the largest construction project in history, when most if Mercury is used to create the orbital structures of the forge around Sol. There, generation ships and drones are built around the antimatter fuel required for a one way journey to any stable, type g star within 7 parsecs, and with fuel enough to arrive and slow down on the other side. There is no coming back. It is part of a goal to colonize the galaxy within 220 million years at most; one galactic orbit of Sol. The main connections to the other systems is a large packaged news stream that is, and must be constantly sent to Sol, and the same is sent from all other systems. It is how rogue breakaway colonies are prevented. The big challenge and looming scare is what will happen when the first colony systems grow large enough to produce antimatter and expand. If any system goes silent in the story era, a poison pill of sorts is launched from Sol to disable their autonomous drones and effectively doom the colony. Antimatter fueled weapons are the nuclear option.

    I am certainly no expert on any of the underlying subjects. It stems from being a fan of Asimov and realizing the myth of the machine gods is a fallacy that has existed in the cultural zeitgeist since at least the dawn of the industrial revolution. The machine gods myth is our Chaos, Ares, and Typhon that will seem equally nonsensical centuries from now. Fusion will eventually happen, but we are already past the phase resource use where industrial technology will deplete all economically accessible sources. ITER is already using a significant percentage of beryllium IIRC. All present industrial tech is impossible within thousands of years or less. The equivalent biological solutions will last stellar lifetimes.

    Anyways, thanks if you made it through my ramblings this far. It is a fun to be a counter culture positive futurist, and conjure a better future history, even if only a dream.

  • True there is a long path ahead, but O'Neill cylinders solve most issues using 1970's materials science. We are unlikely to survive the next providential scale volcanic traps type eruption like the Columbia Basin, Siberian, or Deccan Traps. We must reach the final technology of fully understood biology and an engineering corpus first. Then we unlock interstellar travel. We are already on a rock-ish ship circling the galaxy. The real challenge is when to get off the ship.

    I am stuck in bed around 95% of my day. I am dealing with most of the issues you described.

  • PLA will be better for hardware store and hobby junk. You cannot use automotive class finishes and expect them to last. Generally stick to one brand. Most paints are formulated for steel. ABS is the closest to steel in thermal properties. The expansion is the most important attribute. PLA has a different thermal profile so catalysed 2-part paints will not work very well long term. Rattle can enamel is junk by comparison, but it never fully cures like automotive paints. That property helps it stay in place longer in general. There are special adhesion promoters like bulldog for automotive stuff, but the thermal properties will still be an issue.

    Pro automotive paint is 99.9% sanding and prep work. It is far more intense and rigorous than people realize. Perfection happens in the prep work. The actual paint is just a way of showing off that perfection. Mastering automotive paint is actually all about defeating yourself. Perfection is not subject to your emotions or expectations. It is right when it is perfect.

    You want the highest pressure spray cans as possible. Also, if you do not used all of the can at once, flip it upside down and clear the nozzle by letting the siphon into the empty void and spraying. If you have a compressor that does not shoot out a bunch of oil or water, a cheap Harbor Freight pink gun with the nozzle of the can beside the spray gun will work wonders by atomizing the spray far more effectively.

  • Decompresses my spine and makes me normal again?

  • Gravity prisons suck. Let's plot our escape when the guards are not looking!

  • I haven't kept up with things, but that has to be like bicycle level light and lab conditions. I remember people talking about bicycling with solar and the required area was the size of a pickup truck just to power a basic hundred pound-ish touring kit, and even then it was only pedal assist on a cloudy day or hills. That was only 10-13 years ago. The main issue is that panels are not in any way optimally directional in practice. I expect 40 miles is down hill from the continental divide on I40, after parking the thing in the beam of a solar molten salt energy storage array for a day, during peak solar storm activity, but the fuck if I know bugger all. I know Dave did the math about one of the cars back when he was looking at various EVs. IIRC, no solar panels are more than 30% efficient, most are around 20-25% under optimal conditions. Then you half that or more when they are not directional. That gives a best case baseline for the energy they can produce based upon the sun's output. I know panels have been improving, but we are well past any large scale optimizations and into the phase of scaling production to reduce cost. Do you know what they claim to have changed?

  • I think we may have a language barrier here. Solar panels on a car are a gimmick. They do not do not make significant energy to power the vehicle or charge the batteries. The panels made are a sales gimmick to influence people that do not understand the technology and scales of the system. This is like putting the solar cell for a calculator onto an electric bicycle as an equivalent ratio of size and scope. The calculator runs on 3 milliwatts and the bike needs 300 watts.

  • Yeah. Fucking monsters are a treason against democracy. Anyone involved with their scheme should be criminally liable. They are stealing citizenship from everyone. That is high treason. We should be fighting their hardware AND going after these criminals with pitchforks because it is a soft coup. Trust as a mechanism is not compatible with liberal democracy. Trust is the primary tool of authoritarian monsters. Liberal democracy requires informed skepticism which is diametrically opposed to trust.

  • No country on Earth is like this. No polity is unified without opposition. Additionally, making this statement here, when it is obviously false, in a place where at least half the people are from the US, and likely all of those are left leaning and just as much victims if not more so, seems like rather tepid malevolence.

  • The amount of power from built in panels is negligible relative to the battery. Solar panels are not vinyl film. They are actual semiconductors. They can be thin but are fragile. One can design a panel into some form of shape, but that is not a small task and is only possible with economy of scale for the tooling. Ultra thin solar panels have no real durability.

    I am a pro automotive painter and have owned my own shop twice. I would not want this. Just reproduction body work is expensive. The custom stuff is even more. To make it into frivolous tech, that would cost orders of magnitude more, and the market to make it is so insignificant it would be a massive vanity project and loss. Then it is a nightmare when cars start burning from a few chips to the hood or roof on the highway because someone did not account for the short circuit potential in software and management circuitry. The total power of an optimal solar panel of equivalent size is irrelevant to the scale of an EV battery. Dave on the EEVBlog YT channel has covered this in years past with cars. Use the EEVBlog forum to search and learn more. That is the goto place for EEs.

  • Ask Lemmy @lemmy.world

    Radio wizards and witches, what is the deal with antenna for the ~7 MHz amateur band?

  • Retro Computers @lemmy.world

    AddrFetch on the fediverse

  • Retro Computers @lemmy.world

    Eaternet again

  • No Stupid Questions @lemmy.world

    What will the next age of innovative art culture create?

  • Ask Lemmy @lemmy.world

    For a 6502, what is the assembly convention for calling a 16 bit word into the accumulator from memory to increment as a variable?

  • Ask Lemmy @lemmy.world

    Who is the most super Chad of solo code projects and why?

  • Ask Lemmy @lemmy.world

    Do any of you know the RockChip SoCs well like the RK3388/RK3588?

  • Ask Lemmy @lemmy.world

    How do you work at a job where you fundamentally disagree with the company's ethics?

  • Ask Lemmy @lemmy.world

    Do you have self empathy?

  • Woodworking @lemmy.ca

    Most Functional Wooden Cryptex (16:25) Ebenisterie Eloise

  • You Should Know @lemmy.world

    YSK Lemvotes.org will show you votes on any post, comment, or by user, for anything on the fediverse

  • Showerthoughts @lemmy.world

    The time and expense of commuting is theft, if that job can be done from home.

  • Ask Lemmy @lemmy.world

    What is a word to replace "park?"

  • Just Post @lemmy.world

    The story of Sappho of Lesbos – told with flair – Jessica Kellgren-Fozard (21:49)

  • What is this thing? @lemmy.world

    What is the origin or alt apps that this helmet pad comes from?

  • Lemmy Shitpost @lemmy.world

    Placebo meme

  • memes @lemmy.world

    magical voice

  • Ask Science @lemmy.world

    Is there a direct correlation between overall stomach pH and sweat pH/composition?

  • Ask Science @lemmy.world

    How do you typically build a one off Nichrome wire based heating element for an experiment?

  • 3DPrinting @lemmy.world

    How to design a print with better tolerances – Slant 3D (12:34)