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The newest printers out of prusa, the recently launched mk4 and the much delayed prusa xl are absolutely half cocked. They have interesting design ideas, but a

The newest printers out of prusa, the recently launched mk4 and the much delayed prusa xl are absolutely half cocked. They have interesting design ideas, but are shipping without features that we now know are absolutely table stakes for quality machines. Concretely: the mk4 talks about having input shaping, but doesn’t come with an accelerometer, which is needed for that to work well. The sovol 06 is a much more affordable machine that has similar motion system to the ml3/mk4 The xl really should be a fully enclosed printer like a voron trident or bambu x1 carbon. (The latter two have similar ). If you ignore all the alternatives to prusa machines that are out there, they’re reliable machines that do the thing. But there’s so much amazing stuff in both community driven open source printer designs and also much more affordable manufacturing of the open source designs than you can get from prusa.

sokoloff 4y ago
You do not need an accelerometer for input shaping. You only need one to determine the optimal constants (which represent the resonant frequencies of the machine). Once determined, the accelerometer is not needed. All machines made the same way will be able to use the same constants.
- jimktrains2 4y ago
  Until maintenance is done or the machine is customized, like changing the nozzle or air duct.
  - carterschonwald 4y ago
    Exactly this. It’s almost anti open source/user mod friendly to have a fixed calibration at factory time. Also the level of qc needed to make a one time calibration at factory be accurate for the lifetime of the printer would require an order of magnitude more expensive machine and a service contract to maintain it.
    - sokoloff 4y ago
      If you’re looking for a printer to mod, why start with an expensive and well-sorted Prusa as a starting point? I own 6 printers, 0 Prusas, because I like modding them and don’t see any reason to pay Prusa to give me a better starting point that I’ll just then undo.
      - carterschonwald 4y ago
        Open source == ease of changing it. At least with software, and I don’t see any reason why we shouldn’t have the same expectations for open hardware like 3D printers.
        sokoloff 4y ago
        3D printers are already one of the easiest things to modify. I wouldn’t be surprised if over 1/5 of what is printed is parts/mods for printers. Prusa printers are no different in this regard.
        carterschonwald 4y ago
        3D printers being modifiable does not make it easy, at least by open source software standards.
      - dymk 4y ago
        A Prusa works great stock. But there's always something you can upgrade. I used my stock mk3s for years, but recently decided to upgrade the hotend for a quick-changing one.
cassac 4y ago
Well we don’t really know that an accelerometer is needed for input shaping for a nozzle that is only accelerating across a single plane. The mk4 nozzle only moves on one horizontal axis when printing not two like the XL and the Bambu. Not that I don’t trust your take, but Prusa usually has their ducks in a row and I expect this to be no different. I don’t care about any features of the Bambu line and would continue with Prusa line. They are nice sure but they aren’t that much cheaper with that much better features. You didnt really mention these jaw dropping world changing features so feel free to fill me. I hope it’s more spaghetti detection.
- carterschonwald 4y ago
  You’re forgetting that z hops are a thing. Even in a single axis the load from Eg the filament reel depends on the actual weight of the reel, and there’s almost certainly some variation in the cast aluminum frame parts (internal voids are I’m told an inevitable happening in aluminum/metal casting at scale). I assume the input shaping also would be needed on the bed slinger element as well. As for the bambu, I’m getting voron level performance out of it, though admittedly with a much less open machine. I was using a prusa mini much of the past year but I quickly hit a lot of rigidity issues with its frame that were impossible to address without a total rebuild. I guess for me the issue is simple: most of the plastics which I want to build stuff with (whether for engineering reasons or haptics of how they flex and feel) really require / benefit from enclosed printing. Pla is an incredibly strong material, but it can’t really handle any flex without brittle failure. And I just don’t like that. I’m also in the process of putting together a voron v0, which I expect I’ll use even more due to sheer speed and ease of heating. Nylon and asa and tpu are just so much more gratifying in my use cases.
  - Vecr 4y ago
    What do you think about CPE/Chlorinated Polyethylene? Works fine for me on a Prusa i3mk3s in a room heated to 75 degrees F, with limited drafts (make a tent/enclosure if you have to)
    - carterschonwald 4y ago
sircastor 4y ago
I'd say the proof is in the product. I've read a lot of complaints over the last couple of days that the Mk4 isn't CoreXY, doesn't have an accelerometer, should be enclosed, should be _____. If the Mk4 can produce the same quality of print, does it matter how it gets there? To use a metaphor, Prusa made the very best, reliable car you could buy. Then a bunch of similar cars, that were pretty good were released. And a few really amazing Sports cars were released. And Prusa showed up again with a really reliable, solid car. And people are mad because they thought they were going to be bringing out a flashy sports car.
skybrian 4y ago
"Table stakes" seems hyperbolic here given that we've lived without input shaping at all for quite a while. Speed boosts are welcome but that doesn't mean everyone needs to "overclock" to get the absolute best performance. And if you do want to do that, couldn't you add an accelerometer later?
stevenhuang 4y ago
+1 on the sovol sv06, did a bit of digging and this looks like the best featured printer at the moment for the price point ($350 CAD right now on Amazon prime)
- carterschonwald 4y ago
  Yeah, I would have saved a fair bit of money if I had gotten the sovol 6 as my first machine (though the sovol 5 is a bit more rigid and space efficient)

sokoloff 4y ago

You do not need an accelerometer for input shaping. You only need one to determine the optimal constants (which represent the resonant frequencies of the machine). Once determined, the accelerometer is not needed. All machines made the same way will be able to use the same constants.

jimktrains2 4y ago
Until maintenance is done or the machine is customized, like changing the nozzle or air duct.
- carterschonwald 4y ago
  Exactly this. It’s almost anti open source/user mod friendly to have a fixed calibration at factory time. Also the level of qc needed to make a one time calibration at factory be accurate for the lifetime of the printer would require an order of magnitude more expensive machine and a service contract to maintain it.
  - sokoloff 4y ago
    If you’re looking for a printer to mod, why start with an expensive and well-sorted Prusa as a starting point? I own 6 printers, 0 Prusas, because I like modding them and don’t see any reason to pay Prusa to give me a better starting point that I’ll just then undo.
    - carterschonwald 4y ago
      Open source == ease of changing it. At least with software, and I don’t see any reason why we shouldn’t have the same expectations for open hardware like 3D printers.
      - sokoloff 4y ago
        3D printers are already one of the easiest things to modify. I wouldn’t be surprised if over 1/5 of what is printed is parts/mods for printers. Prusa printers are no different in this regard.
        carterschonwald 4y ago
        3D printers being modifiable does not make it easy, at least by open source software standards.
    - dymk 4y ago
      A Prusa works great stock. But there's always something you can upgrade. I used my stock mk3s for years, but recently decided to upgrade the hotend for a quick-changing one.

cassac 4y ago

Well we don’t really know that an accelerometer is needed for input shaping for a nozzle that is only accelerating across a single plane. The mk4 nozzle only moves on one horizontal axis when printing not two like the XL and the Bambu. Not that I don’t trust your take, but Prusa usually has their ducks in a row and I expect this to be no different. I don’t care about any features of the Bambu line and would continue with Prusa line. They are nice sure but they aren’t that much cheaper with that much better features. You didnt really mention these jaw dropping world changing features so feel free to fill me. I hope it’s more spaghetti detection.

carterschonwald 4y ago
You’re forgetting that z hops are a thing. Even in a single axis the load from Eg the filament reel depends on the actual weight of the reel, and there’s almost certainly some variation in the cast aluminum frame parts (internal voids are I’m told an inevitable happening in aluminum/metal casting at scale). I assume the input shaping also would be needed on the bed slinger element as well. As for the bambu, I’m getting voron level performance out of it, though admittedly with a much less open machine. I was using a prusa mini much of the past year but I quickly hit a lot of rigidity issues with its frame that were impossible to address without a total rebuild. I guess for me the issue is simple: most of the plastics which I want to build stuff with (whether for engineering reasons or haptics of how they flex and feel) really require / benefit from enclosed printing. Pla is an incredibly strong material, but it can’t really handle any flex without brittle failure. And I just don’t like that. I’m also in the process of putting together a voron v0, which I expect I’ll use even more due to sheer speed and ease of heating. Nylon and asa and tpu are just so much more gratifying in my use cases.
- Vecr 4y ago
  What do you think about CPE/Chlorinated Polyethylene? Works fine for me on a Prusa i3mk3s in a room heated to 75 degrees F, with limited drafts (make a tent/enclosure if you have to)
  - carterschonwald 4y ago

sircastor 4y ago

I'd say the proof is in the product. I've read a lot of complaints over the last couple of days that the Mk4 isn't CoreXY, doesn't have an accelerometer, should be enclosed, should be _____. If the Mk4 can produce the same quality of print, does it matter how it gets there? To use a metaphor, Prusa made the very best, reliable car you could buy. Then a bunch of similar cars, that were pretty good were released. And a few really amazing Sports cars were released. And Prusa showed up again with a really reliable, solid car. And people are mad because they thought they were going to be bringing out a flashy sports car.

skybrian 4y ago

"Table stakes" seems hyperbolic here given that we've lived without input shaping at all for quite a while. Speed boosts are welcome but that doesn't mean everyone needs to "overclock" to get the absolute best performance. And if you do want to do that, couldn't you add an accelerometer later?

stevenhuang 4y ago

+1 on the sovol sv06, did a bit of digging and this looks like the best featured printer at the moment for the price point ($350 CAD right now on Amazon prime)

carterschonwald 4y ago
Yeah, I would have saved a fair bit of money if I had gotten the sovol 6 as my first machine (though the sovol 5 is a bit more rigid and space efficient)