3 ms·
The main benefit to the speed will be realized when they scale the build area of the machine. As I suspect they realized it is difficult to get past the physic
by Ccecil 9y ago
The main benefit to the speed will be realized when they scale the build area of the machine. As I suspect they realized it is difficult to get past the physics of the plastic cooling without causing other issues (delamination, warping, etc). The gain will be largely noticed when they are printing with this extruder using a build area larger than 1m cubed. The issue on large printers is being able to get the newly deposited material down while the previous layer has not cooled too much (delamination), although, this can be can be partially controlled with things like heated build chambers and such...they are patented.
This idea was tossed around in #reprap for a few years (I know I have heard the idea thrown out there) and I am glad to see someone working on it. Although, I disagree that a screw drive is needed. I use hobbed gearwheel drive on my extruders and rarely is the issue the hobb slipping. Typically, it is the motor stalling instead. This isn't so much a product of the drive wheel/extruder as it is the hotend not being able to keep up with the commanded extrude volume...since this hotend doesn't have that issue (or so it seems) I suspect the conventional extruder could be used with just a modification to hotend/heater design.
Once the commercial 3d printing market moves up to things like servos, encoder feedback, etc. I suspect the speeds of things will start ramping up greatly. The issue isn't so much the tech but the cost...people are cheap.
edit: After reading the linked arxiv page. I see they are using closed loop servo motors/drivers and a RAMBO controller. They could go faster if they used a 32 bit controller like a smoothieboard or duet instead of the 8bit "arduino based" controllers. {Not saying RAMBO is a bad board, they are known to be very reliable for OEMs}
Not to mention that Smoothieware has the control modules for lasers and cnc built in as well as the 3d printer so it requires probably no firmware modification to get this running...just config and maybe a custom bin. (Disclaimer: I work directly with the Smoothie project so I may be biased)
- lylecheatham 9y ago> Although, I disagree that a screw drive is needed. I use hobbed gearwheel drive on my extruders and rarely is the issue the hobb slipping. Typically, it is the motor stalling instead. Although that may be the problem on your printer, it's simple to fix because one can always add a larger motor. The problem that they solved is that eventually, a stronger motor won't cut it because the hobbed gear will slip, and that's what this paper is all about. Optimizing the motor is done by just upscaling it, but optimizing the drive is what made them to move away from the existing hobbed gear setup. > They could go faster if they used a 32 bit controller like a smoothieboard or duet instead of the 8bit "arduino based" controllers. {Not saying RAMBO is a bad board, they are known to be very reliable for OEMs} I would actually predict a minimal increase in speed. 32-bit controllers don't make for inherently fast printers, they allow for it if utilized properly. What you'll find though is that Marlin and Smoothie both use the GRBL planner under the hood, and generate very similar output. The only major difference I noticed in the output between the two is that Smoothie generates smoother (hence the name) step waveforms. I guess you can also generate steps at a higher frequency with smoothie, but you should be careful equating higher step frequencies with higher speeds, when most of the time people are running with microstepping settings. Higher frequency allows you to get more dynamic range between speed and precision, but that's not really what the paper was about.