The book suggests that error code is either the pogo card or ribbon cable. I have a new print head on the way, I’ll try that first, then a ribbon cable (only $140! 
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The material is sawdust and a couple water-activated binders (still playing with the mix). I actually went to the grocery store and grabbed a bunch of stuff that seemed like it would solidify with water. Tapioca, soy flour, sugar, wheat gluten, etc. Powdered UF glue would probably work great, but I don’t want the formaldehyde.
I’m planning to use this for producing home goods (tabletop accessories, maybe furniture components), hence the material experimentation. It’s also a good story, using a waste product, etc. Looks promising so far, the parts are nice and spongy in their green state and soak up the resin readily. Pretty good surface finish, and quite strong after curing.