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Peachy Printer - The world's first $100 3D Printer

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Re: Peachy Printer - The world's first $100 3D Printer

#81

Post by MertsA »

MBCook wrote: post #75
lumberjack wrote: post #20

Damn I didn't quite realize the ingenuity of using a mirror instead of fixed axis until I read this: >Build volume: There is no certain limit on build volume. In the same way that a flashlight beam gets bigger the further it shines, so does the build volume of the Peachy Printer. Although this has not been tested, we have high hopes to print a full size canoe! This will require a build volume of approximately 3'x3'x1…

But the larger the build area, the harder it would be to control accurately. If you double each axis, could this printer still hit the previous layer when making thin walls?

You're right but the thing is if you're printing some object that is 5x5 feet you probably don't need 0.5 mm thin walls and if you do need smaller features on a larger design you can print the object with the precision portions directly under the center where you have really fine grained precision and the bulk of the object can still be a couple of feet from the center as long as you don't have a need to print a canoe with 0.5 mm walls.

The resolution will look like the graph of dθ/dx with theta being the angle of deflection of the laser. The plot of the resolution with respect to height and displacement can be seen here: http://www.wolframalpha.com/input/?i=h%2F%28h%5E2+%2B+x%5E2%...

What would be awesome is if they made their model printing software optimize the placement of the model in order to maximize accuracy where it was needed but without putting the laser so close that the outside features are crappy including rotating the model maybe upside down if the more precise portion of the model is on the bottom and it is physically possible to print it that way. That'd be a really interesting software engineering project in my book.

P.S. in case anyone was wondering about the math behind the plot, if you integrate the function for a fixed value of h and take the area from x=0 to h you get pi/4 for any value of h which lines up perfectly for a 45 45 90 triangle.

Re: Peachy Printer - The world's first $100 3D Printer

#84

Post by jlgreco »

jonhohle wrote: post #79
Groxx wrote: post #69

Earlier quoted context omitted.

Eh, only if you make the large-ish thing solid - this can easily make hollow / drain-able structures. And since it's partially supported by the liquid as it's built, you don't need as much temporary supporting structure as an extruded plastic version.

In this case, the suspension is some with salt water, which would provide very little support.

The resin is buoyant in salt water; is the cured resin?

So long as the liquid resin floats on salt water, I don't see why salt water should provide less support than liquid resin.

Re: Peachy Printer - The world's first $100 3D Printer

#85

Post by ehsanu1 »

tocomment wrote: post #74

So why does it have to use audio? And why can't it use servos to move the lasers?

Both were due to cost, especially the servos. But I think a microcontroller capable of usb would not be particularly expensive, though more expensive than not having it.

Re: Peachy Printer - The world's first $100 3D Printer

#86

Post by gooderlooking »

stephengillie wrote: post #62
kevingadd wrote: post #7

I wonder how much error is introduced by the use of the headphone jack to drive the printer - you've gotta deal with line noise from the computer's sound card, mixing latency/glitches from the OS, and the device sampling rate, along with any noise introduced on the audio cable. Does a 3D printer like this not actually require high-precision data to work correctly?

I was wondering why they didn't use USB or something similar. How will they interface with, e.g. laptops or phones that don't have a microphone jack? If they're committed to using audio to drive the device, what about a usb audio device, similar to a usb headset with microphone? On the other side of the concept of using audio as their output system, what would a cube sound like if played through speakers instead of t…

The kickstarter video mentions using audio io to reduce cost. Using USB would require a microcontroller and the usb interface. The microphone jack is used for scanning, so as long as your device has 16 bit audio out, I'm assuming you could print just fine.

And yes, I am going to get one just so I can see how Pink Floyd compares to Daft Punk when printed.

Re: Peachy Printer - The world's first $100 3D Printer

#87

Post by peeters »

ehsanu1 wrote: post #85
tocomment wrote: post #74

So why does it have to use audio? And why can't it use servos to move the lasers?

Both were due to cost, especially the servos. But I think a microcontroller capable of usb would not be particularly expensive, though more expensive than not having it.

It also removes a lot of code complexity, or at least moves it to the computer where it's easier to write and update.

Re: Peachy Printer - The world's first $100 3D Printer

#88

Post by samstave »

At this price - I would love to see an array of these printing into a larger vat to produce large objects.

This will make it so meta-printers can be hacked together:

Mount the Peachy onto XY motion capabilities (whats the word for this?) axes? -- and it should be trivial to make a hydrolically lifted resin system that is quite large indeed. (that was the most ingenious part of this design, IMO.

It should be easy to create a resin vat calculator where you simply provide the XYZ dimensions of your container and it will calculate the drip-resolution for you so you know at what rate to adjust the flow to get whatever resolution you need.

I'm getting several of these.

Re: Peachy Printer - The world's first $100 3D Printer

#89

Post by bookface »

bookface wrote: post #50
scotty79 wrote: post #29

Awesome idea. But isn't mirror inertia a problem? Also constant velocity of z-axis movement might pose some inefficiencies because if you want to print a box you have to set the rate of ascend low enough for the laser to create full bottom and you can't speed up when you are building sides of the box.

Just print the box titled a few degrees :-)

s/titled/tilted/

Re: Peachy Printer - The world's first $100 3D Printer

#90

Post by Myrth »

stephengillie wrote: post #62
kevingadd wrote: post #7

I wonder how much error is introduced by the use of the headphone jack to drive the printer - you've gotta deal with line noise from the computer's sound card, mixing latency/glitches from the OS, and the device sampling rate, along with any noise introduced on the audio cable. Does a 3D printer like this not actually require high-precision data to work correctly?

I was wondering why they didn't use USB or something similar. How will they interface with, e.g. laptops or phones that don't have a microphone jack? If they're committed to using audio to drive the device, what about a usb audio device, similar to a usb headset with microphone? On the other side of the concept of using audio as their output system, what would a cube sound like if played through speakers instead of t…

I would imagine any music would print as a random porous rectangular blob
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