GOCUPI Large Canvas and Paint Gondola

On February 10, 2015 by jw

I’ve been experimenting with the GOCUPI drawbot beta board. I’m trying to create large designs on canvas with paint. I had to design and 3D print new motor mounts for canvas corners. I tried paint markers at first, but they’re expensive and unstable so I’ve been printing my own gondola paint pods.

You can download the canvas mount on thingiverse: http://www.thingiverse.com/thing:685404

You can download the paint gondola on thingiverse: http://www.thingiverse.com/thing:685434



Here are the 3D printed canvas mounts with c-clamps. I later added idler posts.





These mounts were too short to allow for full canvas coverage. So I made some extensions:




Of course it wouldn’t be complete with out a 3D printed case for the Raspberry Pi and the GOCUPI Beta board hat.

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This is the first painting on canvas I did with GOCUPI:


(it was still drying in this photo ^ light is coming in from the back showing the canvas frame)

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Before I started with the canvas, I ran a test print on paper.


I transferred my starting point from the paper to the canvas by poking a hole through the paper with a pen. This is where the gondola needed to start to make an exact copy of my test print.

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Now I prepped the canvas with primer and edging effects.


This was done simply with a piece of cardboardIMG_0227


And we’re off!


Everything is going good…


Not bad…


Then the Raspberry Pi crashes (I think it over heated maybe?). GOCUPI stopped and I have an unfinished painting. I decided to try and restart the machine, but only draw the unfinished lines. I took a photo of where it left off, brought it into Photoshop, made a mask to only show the unfinished lines, then ran the result though the TSP generator. I did it this way so I could know exactly how the remaining lines would connect. Since I’m not using the pen up servo, I wasn’t sure how the lines would connect if I just started deleting things in Inkscape.




Finally I sprayed on some oil based stain


Let dry and hang


Before I started this painting I ran a bunch of tests on paper:

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I had some warping issues here, I’m pretty sure it was my poor measuring. I started using a laser measure and it helps a lot.

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Here are some videos of it in action:


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