How’s this for useless? After nearly two decades in manufacturing as a CNC programmer and machinist it’s a natural progression for me to try to turn any and everything into a programmable machine. I’m not the first person to bolt stepper motors to an etch-a-sketch and use a computer to control them, nor am I the first to blog about it, but I might just be the first person who plans to take this useless contraption to the next level.
I found so little in the way of etch-a-sketch specific configuration files or software, none actually, I was forced to figure it out. And I really want my grandkids to have access to those things. Have you ever tried to automate an etch-a-sketch? It’s not easy. The mechanical meat of an etch-a-sketch is a somewhat complicated system of pulleys and wires with a cheesy little stylus that scratches aluminum dust off a piece of glass. Since your only exposure to using an etch-a-sketch has likely been the old fashioned way you’ve probably never thought twice about the huge amount of backlash this cheap, mass-produced system inherently has. A computer doesn’t know anything about this backlash, it must be taught to compensate for it. For some reason the amount of backlash present is not constant, that makes compensating for it a total bitch. You also have the problem of scaling, that is figuring out how many turns of the knob will move the stylus one machine unit. The machine unit can be what ever you want it to be, inches, millimeters or even cubits (applicable only to drawing arks) Scaling is complicated greatly by backlash, especially inconsistent backlash. There are purely mechanical challenges as well, such as how to attach the motors or how to ‘reset’ the display with all that shit attached. To properly interface an etch-a-sketch to a computer you’ll need a plan, a few parts, some tools, probably even a few nuts and bolts, but most importantly you’ll need a piece of properly configured software to run the show.
Trying to convert an etch-a-sketch into anything even resembling a precision tool will truly be a challenge, which is why it must be done. I will be using the Enhanced Machine Controller to run my etch-a-sketch. I believe outside of writing your own software to control the motors directly, there exists no other piece of software that will allow the level of tweaking I’ll need to do in order to get consistent, attractive results. I don’t believe it’s possible for a computer to do a great job on one of these things without being able to configure how the motors are handled down to the smallest detail, and EMC can deliver. Can I? These seemingly insurmountable odds are why I scoff at people who talk like computer etching one of these and selling it as unique expensive art is somehow dishonest or cheating.Even after all this I still have to generate a toolpath. I have to draw a picture with a single unbroken line. To them I say, ‘bet you can’t do it’. 
I'll be posting how I got this far, just incase I have something worth adding. Also I've decided to go with the pocket sized etch-a-sketch for a couple of different reasons.
1.The pocket sized ones have a much tighter mechanism, I'm not sure why, but of the ten or so I tried out all of them had minimal backlash.
2.They also seem to draw a much sharper line.
3.The smaller size also opens up new design possibilities. I've decided to automate the 'display reset'. This should be pretty damn fun.
A very short video clip from before all the kinks were worked out.
Unfortunately, I was forced to abandon this project along with every other one I had. This included several not yet blogged about. The good news is that it looks as if things are starting to turn around for me. Not only do I finally have the opportunity to put my life back together, I have access to some really cool project fodder. But still, another etch-a-sketch is in my future.
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