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Jello 3D Printer (2013)

spritesmods.com

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Re: Jello 3D Printer (2013)

#4
It would have been a cool project, even if he used 8020 extrusion like most similar projects.

Instead, he used salvaged gear for this: He pulled old stepper motors from hard disk drives, and even used an old laptop battery as a power supply. Impressive!

Re: Jello 3D Printer (2013)

#6
it seems that a lot of cheaper CDROM drives position their laser by using a standard, imprecise DC-motor and using the laser tracking as feedback.

Besides cost, the track on an optical disc runs in a spiral, and thus the continuous motion of a DC motor is advantageous because the feedback loop is adjusting the linear velocity of the head instead of its absolute position, whereas a stepper motor would have to make discontinuous jumps. This helps tracking performance and decreases noise (both electrical and acoustical.)

Re: Jello 3D Printer (2013)

#7
> On startup, it'll run the carriage into that switch so it knows exactly where it is. With my setup missing that switch, how does it know where the carriage is? Basically by doing the same thing: it'll run the carriage into the end stop for a good while. If the carriage reaches its limit, it'll slip back and stay there. This gives quite some wear-and-tear on the mechanics and isn't the most elegant solution by a long shot, but for a device that isn't used much and with me not having enough GPIOs left to hook up switches, it had to do.

As I understand it, this is basically the same solution the Apple II disk drives used to return the head to track zero. Owners of the Disk ][ will remember the loud repetitive clicking sound it made at startup. That's the sound of the drive controller moving trying to move the head outward 40 times and hitting the end stop most of the time.

Re: Jello 3D Printer (2013)

#9
post #3

This is so cool! And it's from 2013, thats amazing. A very similar printing method is being explored by MIT's Self Assembly lab, I think they first published in 2017 - https://selfassemblylab.mit.edu/rapid-liquid-printing https://www.liebertpub.com/doi/full/10.1089/3dp.2017.0037

The non-obvious way to greatly speed this method up is to use an array of nozzles and dip them all at the same time. Draw them upward while squirting your resin at the appropriate times and you have a 3D printer that prints as fast as you can move something up and down...

Imagine a sewing machine, but every time it moves up a 3D part is left behind in a binder. A new container is whisked in to replace it and the process repeats. Patent #10,870,239 issued, and more are pending :)

Re: Jello 3D Printer (2013)

#10
post #3

This is so cool! And it's from 2013, thats amazing. A very similar printing method is being explored by MIT's Self Assembly lab, I think they first published in 2017 - https://selfassemblylab.mit.edu/rapid-liquid-printing https://www.liebertpub.com/doi/full/10.1089/3dp.2017.0037

His whole website is an absolute goldmine of awesome projects and hacks. I thought this was really cool: Optical Mouse Cam: https://spritesmods.com/?art=mouseeye
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