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Joined 1 year ago
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Cake day: June 9th, 2023

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  • As someone that has learned FreeCAD/slicing/printing and someone that can set feed, speed, and sizzle bacon with a side of chips, I’m not as proficient/experienced with machine tools as I am with design and printing, but for the time I’ve spent doing both, the total learning curve is about equivalent in my opinion.

    See, the thing is, with 3d printing functional stuff, you can’t just grab a file and print like this. It sounds plausible in theory, but it is honestly a recipe for a Darwin award when handling tiny explosives (primers technically are) like ammunition for firearms. This can be difficult for many people to grasp, but consumer 3d printers are accurate, but not precision machines. This constraint of accuracy without precision is important. In the most basic explanation, the movements of the printer begin by assuming a 0 (x) and 0 (y) position. All movements assume they are relevant to this 0,0 location and absolute. There is always variance in this 0,0 location.

    If you get deep into the weeds, there are also several factors that make every 3d printer’s motion system unique to where two files will never print exactly the same between two machines. It does not matter at the tolerances of most parts people share, but this is usually at least 0.1mm-0.5mm tolerances. For something like a gun, or other precision mechanism, you really need a design tolerance of 0.01mm to 0.05mm. This kind of tolerance is beyond the capability of most cheap machines and beyond the kinds of tolerances that can be shared in files with other people and have any kind of relevance. The reason this matters is because the printed parts need to interface with external toleranced parts like the steel barrel. It is very possible to print these parts, but the technique requires skill. One could start scaling a part to try and solve this issue. However, in almost all cases, the X Y and Z axis will have different tolerance ranges that need to be accounted for in the design.

    The actual functional way to do this requires designing your own parts. Most people that are sharing stuff like gun prints are really just showing off their chops. A fool might try and just print the stuff, but fools rarely get very far on their own. I might take such a file as a baseline to further play around with in design, but I am far more likely to place the part in FreeCAD and use it as a visual reference only while I rebuild the item from scratch. I can easily dial in 0.01mm tolerances, but I do so in reverse. I print many unit tests and adjust my design measurements until the test prints match my real world measurements. I’ve spent thousands of hours in CAD learning to design well. I can easily design something like a functioning gun. I do not support others doing so or showing off such content because I think it is irresponsible. This is why the general community consensus, and I banned (real) gun related content from !3dprinting@lemmy.world. I love functional printing and design at these levels, but the subject of guns is not conducive for a healthy general 3d printing community. Not to mention, it is the kind of thing some foolish kid might try without a full understanding of design, and accuracy versus precision.

    Systems like a CNC mill use absolute position motion systems. With these, there is no assumed relative position; if the motion command fails to produce the specified movement there is direct feedback and error handling. Closed loop linear motion systems are far more expensive and/or difficult to realize. These are the basis of any real concern. The ability to print something truly robust enough to function like a gun is a matter of quite skilled learning and practice in the real world.



  • I find these articles funny. A glock switch can be made out of almost anything from a bit of bent metal sheet to carved wood. 3d printing one is irrelevant. When it comes to guns, the arguments are usually idiotic. I can making nearly anything with a small lathe and mill. The gun problem is a multifaceted cultural problem. Their misuse is largely the result of hopeless disenfranchisement of the poor and average person, along with politically leveraging ignorance and corporate capitalist abuses.

    How you doing Squid? Any progress on the food health front?



  • That is not how real point of sale systems and stores operate in practice. I actually managed a retail chain of bike shops as the Buyer and back office manager. I was the one maintaining the point of sale connections and system. There are always errors in these systems largely due to new and incompetent sales staff that sell/return/enter duplicates of the wrong items. They can enter almost anything wrong, from gender to color, from model year to brand. I’ve seen them all.

    Connecting these systems online is an absolute nightmare. I tried it with shopify, but had to limit the sku’s to items I could completely control with minimal intervention from other staff. Generally speaking, the POS system in a local retail store can be more loosely managed where the staff can make up the gaps and mistakes when the POS system numbers do not perfectly match the local stock. If you want to track inventory like is required for online retail, you need a whole different kind of micromanagement and responsibility from staff. You also need something like quarterly inventory audits. These are quite time consuming and are a total loss in the labor time involved.

    For online retail to be competitive, the margins with e-tail are absolutely untenable trash for brick and mortar retail. They are not even close. The biggest expenses are the commercial space rent and labor costs. With e-tail, the labor is less skilled, and the space is a cheap warehouse somewhere remote. General retail margins must be 40%+ while e-tail is 15-20%. The two are completely incompatible. This is why real quality brands do not sell e-tail. It has to do with how distribution and preseason wholesale buying works. There is more complexity to this, but overall the two are not compatible. In fact, most high quality brands will not allow most of their products to be listed online except under certain circumstances. This is to keep things fair to all parties and prevent undercutting based on whomever has the lowest overhead cost.

    Selling online is only for low end junk and certain circumstances. If you are a high end consumer, you will likely understand this already. It is hard to produce high end goods and distribute them successfully. It takes local Buyers that know their niche market and can do massive preseason spending to collectively give the manufacturer an idea of what they need to produce at what scale. Otherwise, the business will not last long, or they must produce lower end and more reliable/limited products. This strategy will likewise fail due to over saturation of the market segment. It is far more complex than most people realize.


  • Yeah this has been my experience too. LLMs don’t handle project specific code styles too well either. Or when there are several ways of doing things.

    Actually, earlier today I was asking a mixtral 8x7b about some bash ideas. I kept getting suggestions to use find and sed commands which I find unreadable and inflexible for my evolving scripts. They are fine for some specific task need, but I’ll move to Python before I want to fuss with either.

    Anyways, I changed the starting prompt to something like ‘Common sense questions and answers with Richard Stallman’s AI assistant.’ The results were remarkable and interesting on many levels. From the way the answers always terminated without continuing with another question/answer, to a short footnote about the static nature of LLM learning and capabilities, along with much better quality responses in general, the LLM knew how to respond on a much higher level than normal in this specific context. I think it is the combination of Stallman’s AI background and bash scripting that are powerful momentum builders here. I tried it on a whim, but it paid dividends and is a keeper of a prompting strategy.

    Overall, the way my scripts are collecting relationships in the source code would probably result in a productive chunking strategy for a RAG agent. I don’t think an AI would be good at what I’m doing at this stage, but it could use that info. It might even be possible to integrate the scripts as a pseudo database in the LLM model loader code for further prompting.



  • I think, printing more money under the same conditions is the primary inflation/devalue, while the federal interest rate determines the baseline for loan interest rates. If the federal rate of return is high, it makes no sense for anyone to buy loans for a lower rate as the US gov has a longer upstanding record of paying back those debts/returns. If the fed is paying a high baseline rate, so is everyone else. Why would a bank or anyone buy your debt if they can put that money in government bonds and get a higher or the same rate of return. So money is expensive because the federal rate is high. At least that is my most simple understanding.



  • So as far as bike fit and road, if a road bike is fit properly, you won’t have weight on your wrists or hands. It probably sounds a little unintuitive, but a proper bike fit on road is all about balancing your weight so that your upper body is neutral without any weight on your arms. Like, the primary test to see if your saddle position is correct is to see if you can pedal smoothly on a trainer while taking your hands off the bars completely.

    The key here is that the centerline of the crank arms is the fulcrum of the rider’s balance. The adjustment of this balance point is set by sliding the seat fore and aft, thus placing more or less of the rider’s posterior to the rear of center.

    The only reason I can still ride is because my thoracic (spine section where the ribs are attached) is neutral when I ride, which by inference also means my arms must be neutral too.

    I am totally fine with people that don’t wish to try it or cycle for whatever reason. I’m simply trying to relate that road bikes are not like any other kind of bike. They are intended to be fine tuned to one’s anatomy, and this makes it possible to ride even when many other forms of exercise are not possible. I can’t swim or do anything sitting upright, standing, or reaching, yet can ride. GL. I wish you the best.


  • I was overweight in my late teens and by my mid twenties I was in really bad shape at 340lbs at my worst. I was in a Target with serious chest pains at one point. I'm not a whiner type and have a significantly above average pain threshold, but I wondered if I would even make it back to my car and get home that day. That was in '08. By '09 I had to move back in with family and started riding a bicycle everywhere. I had tried running and rowing when I was younger, and when I was overweight, some of that was from semi regular gym visits and weight lifting. Nothing ever really stuck like a real lifestyle though. They were always things I made myself add to my routine. I tend to overheat from aerobic exercise. Overheating in this context is really hard to define in a relatable way because it is such an intimate concept to my self awareness. Mainly my head tends to get much hotter than the rest of my body in such a way that I am extremely uncomfortable. I can easily put up with that unpleasantness. If I had never gotten into hardcore cycling, I wouldn't have known this unpleasant overheating was even a thing separate from exercise itself.

    I come from a background of hot rodding cars. Internally, I always had this notion that I was failing at life if I could paint cars, airbrush graphics, build motors, and fabricate at such a high level, but couldn’t do the same with myself and my body as the driver. This curiosity is a major driver in why I rode so persistently through the first couple of months to get past the worst discomfort and made it to a routine. The part that made it different from all aerobic efforts previously was the airflow on a bike, it’s massive. The cooling effect got me. I resisted the clothing at first, like everyone does, but after realizing its utility and purpose, it unlocked the cooling effect even more. I made it to under 190 lbs, worked in a bike shop, and raced. It was really the best I had ever felt in my life by a long shot. The lack of impact with cycling also has a fantastic effect on loosening up your body and improving aches and pains. I had felt like I was aging in addition to chest pains and other problems when I was 340lbs but that all went away with riding.

    I was super unlucky and was partially disabled by a driver in '14. I had a bunch of broken bones and barely survived. I now walk around slowly, and can’t hold posture for very long at all. Still, I can ride. It is nothing like it was in the past. I can only do ~30 miles in a day regularly when I could pull a 100 mile day weekly in the past, and have ridden 200+ miles in a day before. At the present, it does not feel like I can or should be riding, but so long as I maintain my routine that includes nearly daily cycling, I am empirically in my best shape in terms of the least aches, pains, and problems even with severe chronic problems. There is no chance I would be able to establish such a cycling routine from my current state, but I came into my condition as an amateur racer, so I had that advantage and never lost my race legs. If at all possible, consider road cycling. Get a proper bike and get someone to fit you on the bike (adjust and swap required components to fine tune your anatomy to the bike) because with road, the little details are super important or you’ll cause issues from that level of repetitive motion. There are a lot of disabled people on bikes too. In a shop, I was the Buyer and often helped people with unique needs. It may not be right for you, but is maybe something to think about. Cycling changes more than your physique, it impacts your physical and mental health in profound ways. Cycling really is a lifestyle. On a bike your both free and anonymous for the most part.



  • Not really. There are very few lobbyists for a non dystopian future. The battle for the right to own your tools is the absolute fulcrum of the future and the next several centuries. The loss of ownership rights is the largest sociopolitical issue and regression of the past millennia. The atrocity of feudalism was already hashed out as a terrible and failed social structure. Allowing it to reemerge will have extreme long term impacts

    The way people fail to see and understand this issue speaks to the potential force needed to shift the trend and trajectory. All it takes are a few influential and connected people working to shift the political conversation and momentum in the opposite direction to alter the course of the future. Funding a few individuals to speak up for us could make an enormous impact. Ownership IS citizenship; IS democracy. Trusting others while renting tools and property IS feudalism. It is a path to slavery in all but name. It happened before, and is always the inevitable outcome of this situation. Putting up any fight against the lackadaisical complacency of our present culture absolutely has the potential to impact the future in a substantial way.







  • I will counter that the definition of intelligence is needed. Yours OP seems to be emo intelligence, maybe social intelligence. One can be very intelligent in other areas while not within these.

    My quality would be a person’s ability to abstract and understand subjects through inference and intuition; to see all the layers of bigger pictures and the uncertainty of truth when contextualized.

    In many ways, I fail at my own stupid, but it is a striving in life. After all, what use are achievable goals.

    Stupid is subjective, circumstantial, and non binary.