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

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  • I’m a mech E in the medical field. We’re consistently understaffed. If I validate an Excel worksheet in Excel '08 or a Python program in 3.5 with a specific version of NumPy, we’re probably sticking with those versions for a while. Every time I bring up re-validating with the latest version, keeping one old system running the old software requires fewer resources than me or a colleague re-validating.

    My whole department is stuck on one version of Python because that was the most recent version when I had an emergency project and developed a data analysis algorithm. We validated it, then as new members were added to my team, they needed a copy, so we had to keep using it. I’ll probably re-validate it to the next Python release. It’s not only unit tests, or we could automate validation. Unit tests are a tiny part of validating software for making medical decisions. And software that directly runs a medical device (like firmware on an insulin pump) is an order of magnitude more rigorous than what I do.

    Side note: there are people who somehow root their insulin pumps and run algorithms on them. There’s a group that can get a PID control loop on an insulin pump that has a more simple control scheme on it (because that’s how the FDA approved it). The company has been trying to get approval to use PID control in the US for years.



  • My third printer, I paid $70 for, used (ender 3 pro return). It was missing several small components, one big part (top aluminum extrusion) that required some machining with a drill press, and had a bad thermistor.

    I don’t think you can get a beginning printer for $100 unfortunately. Sovol and Anycubic make printers among the cheapest that are more beginner friendly (I think) than Ender, for roughly the same price. I have a friend with a Creality and an Anycubic Vyper, and the Vyper seems to be more beginner-friendly. I have two Crealitys and I love them, but both required a ton of modifications to become reliable.

    Can you check your area for a local maker space? My local library has 3D printers for anyone under 18. Universities typically have a few of different technologies (SLS, SLA, FDM)


  • There are methodical ways of valuating a private (and public) company. Some are pessimistic and some are wildly optimistic. Your can legally use whichever one you want, only you must only use that valuation method for everything. It’s illegal to value the company low for taxes and high for loan collateral. And if you sell it, you can owe back taxes if your valuation was off (sale price is the new valuation).

    This is overly-simplified US accounting rules (from finance class 10 years ago)



  • If you have a filament runout sensor, the klipper default settings aren’t great. If the sensor activates, the printer shuts down after about an hour, losing your home position. With a part on the bed, you can’t re-home, so it’s a wasted print.

    The mesh leveling isn’t automatic either. You might want to add either auto-load your default mesh leveling if you always use the same print surface, or put mesh leveling codes in the starting G-code section of your slicer.

    I ran the pressure advance tuning and found that I needed a ton of pressure advance. My prints turned out much better.

    I also got improvements by reducing the allowable deviation in the slicer (G-code files get much bigger, though), and I load files as STEP files directly in Prusaslicer. STL doesn’t have curves, it’s a series of planes. STEP files have geometric primitives and can have curves.



  • Seriously? I was looking at a Surface product recently, and it appeared to have an access panel for the NVME drive. I read a ton of complaints about the dimensions of the drive being unusual, but access to it was easy. I don’t think I was looking at a Surface pro though.

    If a surface pro wants to be a full OS and not a tablet OS, it should be easy to replace the storage device.




  • The one thing I didn’t like about klipper firmware on my CR-10 was the default filament runout setup. One of my first big prints (with expensive ApolloX filament) ran out. The default klipper setup waits something like an hour, with the hot end still hot, then completely shuts down.

    So my home position was lost, and with a partial part on the plate, there was no way of re-homing, so it was a wasted part.

    Make sure your filament runout timeout is set to 24 hours (and I think I might have made the temp lower so it didn’t burn?)

    I like klipper on mine, too. I do wish the default mesh would be loaded at startup, but it doesn’t load any mesh. Which doesn’t really matter, I guess. I have four build plates, three different styles, so I’m running bed levelling pretty much every print anyways.



  • Kale@lemmy.zipto3DPrinting@lemmy.worldSuggestions on print settings
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    9 months ago

    Second this. If it’s PLA, improving layer cooling might help stiffen the last layer before the next is applied. If it’s not PLA, slowing the print down can reduce the horizontal forces for slower-cooling filaments like PETG/ABS. If there’s any warping or over extrusion leaving little blobs on the surface, your nozzle can bump into them, breaking cantilevered features like this one, or breaking the part off the build plate. Getting retraction to blob less or making sure no over-extrusion exists could help. If it’s PETG or Nylon, printing slightly wet (where the surface doesn’t look bad) can cause blobs on the top layer that the nozzle hits and causes those horizonal forces.

    Drooping like this means something is too soft (speed up cooling on PLA, reduce print speed to give more cooling time and better layer adhesion for any material)

    Prints like this aren’t impossible. I’ve printed a PETG storm drain that had vertical slots like this when I couldn’t buy one I needed. It turned out great but I had to print really slow.


  • Kale@lemmy.zipto3DPrinting@lemmy.worldFirst print with PETG
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    10 months ago

    My first PETG print was amazing. One of the best prints I ever did. Then I had 10 failures in a row. I went though 3 half rolls (kept changing them thinking it was cheap filament).

    I had a CR-10v2 with the OEM bed springs. I stiffened them by adding a bunch of washers since it’s recommended to upgrade the OEM springs. Suddenly I had mostly good prints. I bought a filament dryer and started printing directly out of that. That solved most of the rest of my problems.

    PETG is the “second easiest to print” because it can print below 250 and doesn’t need an enclosure, but that’s only part of the picture. It’s really picky with your first layer height, it doesn’t stick to itself very well with a layer fan on it, and it absorbs moisture (I live in a swamp, I have to print PETG out of a dryer).

    I find ASA easier to print than PETG with most prints, with only a few warp-prone shapes where ASA is difficult. I try ASA first and keep more spools in hand than PETG.





  • Kale@lemmy.zipto3DPrinting@lemmy.worldPlate difference
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    10 months ago

    I’ve got one now with a V6 knockoff hot end, steel PEI print bed, and running klipper firmware. It was backup printer, and now it’s the backup to the backup (purchased Comgrow $70 used Ender 3 pro).

    I’d like to give this to a friend that’s interested in printing, but I’d have to flash back to stock firmware. The buttons and display don’t work with klipper, and I don’t have a spare raspberry pi.

    It’s still relevant with the upgrades I made to it, except it’s still has really noisy steppers, and the build volume is so small it’s really limiting. I think the Prusa mini is still large enough to be practical. The monoprice is mostly relegated to toys.

    I need some 18650 holders for a project which the mini can do great with, but I need a lot and printing them two or three at a time won’t cut it.


  • Kale@lemmy.zipto3DPrinting@lemmy.worldResin Printer Not From China?
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    10 months ago

    Even with moderate usage, no joke, I’d recommend getting a flammables cabinet to store IPA. At the end of every weekend, I drain our washing station back into two three liter jugs and put them in the flammables cabinet. I drain them while the washer is running to get the solid stuff out of the washer. They’re stored correctly, the cabinet prevents light from reaching the jugs, and the solids settle to the bottom of the jugs over the weekend. On Monday I carefully pour the top portion into the auto washer and top it off with new IPA. The settled layer gets poured into the waste container.

    We have two printers at work, one wash station and one cure station. And we have 8x jugs of IPA in our flammables cabinet.

    Before we started settling in the cabinet and decanting our wash solution, we went through an incredible amount of IPA that we had to deal with as waste. And this is from two SLA printers, which we use in addition to our Prusa MK3 and SLS nylon printers, so we don’t always use the resin printers.



  • Thanks for the link.

    It wasn’t an issue with my monoprice, so I might have skipped over some warnings. Then I didn’t read up on all of klipper documentation because I was familiar with it. Maybe I’m warning others about something that’s in the documentation anyways.

    The stupid thing is that I’ve had this happen with my Ender 3 Pro when hooked up to pronterface. I had forgotten it had happened.