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Jello 3D Printer (2013)

spritesmods.com

11–20 of 25 posts

Re: Jello 3D Printer (2013)

#11
I love this.

I wonder if buttercream or whipped can be extruded through a needle without deflating. Could be pretty tasty.

With a bit of refinement this could probably be productized. Branded jello shots would be great for bars and events.

Re: Jello 3D Printer (2013)

#12
post #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!

So impressive. Its like an implausible macgyver scenario in an action film.

Re: Jello 3D Printer (2013)

#13
post #11

I love this. I wonder if buttercream or whipped can be extruded through a needle without deflating. Could be pretty tasty. With a bit of refinement this could probably be productized. Branded jello shots would be great for bars and events.

the post is quite old (2013)

http://www.printadrink.com/

it seems some company did it. (seen in the comments of the blog)

Re: Jello 3D Printer (2013)

#14
post #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 lon…

Wow. Makes me wonder how the head could maintain its precision with so much mechanical hammering.

Re: Jello 3D Printer (2013)

#15
post #2

I first thought it prints gelatin. Then I thought it was made of gelatin. Now that I see it prints IN gelatin, that's pretty awesome.

Based on the science described in mark robers jelly pool (where he makes an actual proper size pool of properly set jello/jelly), probably not possible to print proper gelatin. At least not without it being a bunch of tiny particles rather than a congealed clean solid: https://www.youtube.com/watch?v=DPZzrlFCD_I

Or at least, not without it taking forever.

Re: Jello 3D Printer (2013)

#16

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 dis…

Except that a CDROM wants to be able to seek quickly (say 100 milliseconds) while also read a disc at 1x speed (taking 75 minutes).

Having a DC motor which can run smoothly across 5 orders of magnitude is pretty much impossible. Stiction will always be more than 0.05% of the motors power output.

You therefore have to use a "go-stop" approach based on laser feedback instead.

Re: Jello 3D Printer (2013)

#17
post #14
post #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 lon…

Wow. Makes me wonder how the head could maintain its precision with so much mechanical hammering.

The endstop can be designed with springyness.

Then the process is "move towards the endstop", then "switch off the motor current, if we are pushing against the endstop spring, then we'll be pushed back a step". Repeat this process 40 times.

Re: Jello 3D Printer (2013)

#18
post #14

Earlier quoted context omitted.

Wow. Makes me wonder how the head could maintain its precision with so much mechanical hammering.

The endstop can be designed with springyness. Then the process is "move towards the endstop", then "switch off the motor current, if we are pushing against the endstop spring, then we'll be pushed back a step". Repeat this process 40 times.

Nice idea. I guess you can also measure from the coil current that the motor is being stopped or pushed back.

Re: Jello 3D Printer (2013)

#19

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 dis…

Except that a CDROM wants to be able to seek quickly (say 100 milliseconds) while also read a disc at 1x speed (taking 75 minutes). Having a DC motor which can run smoothly across 5 orders of magnitude is pretty much impossible. Stiction will always be more than 0.05% of the motors power output. You therefore have to use a "go-stop" approach based on laser feedback instead.

'Stiction' - the static friction that needs to be overcome to enable relative motion of stationary objects in contact.

As a non-native english speaker I assumed that was typo and had to search for it. I will also assume I wasn't the only one.

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