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Joined 1 year ago
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Cake day: June 13th, 2023

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  • I am aware of the basic arguments behind inflation/deflation, and neither is good in excess.

    Typically central banks targets inflation of 2% these days, but we all know the real inflation for necessities is far higher (>4%). Inflation disproportionately affects the poorer - rich people have the fast majority of their wealth “stored” in stocks or real estate, which rise in valuation as people rush into these markets to protect the little they have. I’d argue that inflation rates are artificially pushed far higher then is sustainable, simply because those who decide are the same people who benefit the most.

    I consider a low but predictable inflation rate about 1% ideal (0-2% is acceptable short term variation) for the following reasons:

    • No one has to worry about debasing/devaluing your currency by injecting more supply.
    • Nobody “passively” gains wealth by sitting on it.
    • If you want to keep your wealth, you have to take some risk and use it.
    • Inflation rate is not so high, that you need super high risk investments to keep up, making it more accessible to small players.
    • Large player can not as easily game the market by skimming of value from the lower to upper middle class.

    Yes, this idea is not without risks. But the way I see it the forced “we have to improve value by 2% every year” exponential grow can only go on so long before we (humanity) hit the finite limits of this planet.














  • The signal does not care about how it gets from the sender to the receiver. The only thing that matters is that at the receivers end 0s and 1s can be separated. One common measurement is the eye pattern. If the eye is “open” enough (=matches the spec), communication is possible.

    Impedance mismatch causes reflections (visible as oscillation after rising/falling edge), differential pair line mismatch degrades the slop of the signal transition (rising/falling edge). Geometric features only matter if they are large compared to the signal wavelength. As a rule of thumb features smaller then 1/20th of a wavelength can be safely ignored, often times a ratio as large as 1/5 works just fine. USB3 uses 2.5Ghz (5Gbit/s) or 5Ghz (10Gbit/s), where 1/20th result in 3.4mm and 1.7mm respectively (assuming an effective dialectic of 3.17). This is still grossly simplified, because in many real systems you don’t control the entire transmission line (eg. user buys a random cable and expects it to work), so it makes sense that the USB consortium specifies eye patterns and factors in various system uncertainties.

    RAM on the other hand uses 16/32/64/128 single ended data lines, with a dedicated clock line. Data does not have to arrive perfectly at the same time, but the margin may be as little as 1/10th of a clock cycle. Here accurate length matching is absolutely required. Its also the reason why the same CPU + RAM combination may archive higher stable clock rates on some mainboards then on others.





  • What filament do you want to use? Well tuned PLA might be able to bridge that far, no chance with PETG. What is your maximum acceptable sag?

    It seems like the bridge lines do not attach to anything at the very end on the layer below. In Orca Slicer you need to enable “Ensure vertical thickness” to enforce that. I’d also rotate the bridge direction by 90°, this cuts down the length of the longest bridges by half. Bridge line spacing looks good to me. Make sure that the layer on top of the bridge is printed slowly and does not start in the middle, otherwise it will be pushed back and forth.

    If it is just a mock-up, consider partially filling the interior or enabling “make overhangs printable”. Both will alter geometry, but so will excessive sagging.


  • A lot of people here commented “I do X and it works for me”, but I do not think that is good advice. While it might work fine for that person, there are too many variables that are ignored. Ambient humidity, filament type, printer model, slicer settings, model geometry/details - all of this has an impact on the final print quality.

    A more controlled environment removes variables and therefor makes the print result more predictable. Drying filament and storing it properly takes a bit of effort, but it is easy step towards better results.

    You don’t even need a dedicated dryer, just use your printers headbed, put 1-3 spools on it and a cardboard box with a few vent holes on top. Set the temperature according to the filament and let it run for 8 hours. Afterwards put the spools into a sealed container (4L cereal box works great), add some silica gel and your done. When it cools back down the relative humidity drops below 10% RH, which is so low that most hygrometers wont even measure it.

    I’m casually printing PETG at 260°C, over 20mm³/s (about 300mm/s) and archive reproducible near perfect results with next to no stringing. With bare PLA drying may not matter, I’ve too little experience to give a definitive answer. If you have any composite filament (wood, carbon, sparkle, etc) you definitely should dry it anyway, because you do not know how much the filler changes the properties.

    Oh and finally: I place new spools in containers with dry air (a tiny bit of silica gel in them) and measure the equalized humidity after a few days. Most spools were delivered with a humidity of 15-20% RH