Sketchbot Prototype Sculpt, Phase 4, Part IV

Magic Sculpt is the bomb! This stuff hardens like a rock and sands very nicely. Spent about 6 hours today sanding and detailing. Drilled out the holes for the rivets, which will be filled with ball bearings just past the half-way point. My best friends today were a set of three tiny jeweler's files. Looks like I'll need another pass of Magic Sculpt for tonight, try to finish up tomorrow and start the next mold. A few more comparison pictures up on Flickr.

Sketchbot Prototype Sculpt, Phase 4, Part III

Success! Ok, after the 2nd attempt, but still, I'm much happier that I got a workable positive out of my problematic first mold. A few mental notes: use larger pour holes and keep in mind the 3 minute pot life next time. I can now machine this version and further refine without worrying about all that chipping and instability from my fragile Sculpey original. Also, the next mold will be created with firm acrylic walls and be better leveled for a tighter seal.

EDIT - I forgot to mention that after consultation, I built up the front side of the mold with additional silicon material. This allowed me to move forward and get a workable positive!

Sketchbot Prototype Sculpt, Phase 4, Part II

I poured the 2nd half of the mold this afternoon, and after 4 1/2 hours of letting it cure it appears that it's still squishy in parts. As I feared, the top half is way too thin around the eye opening to hold a proper shape. You can even see the mold creased a bit and I've got an awkward line running through the upper front portion. Grrrr. Additionally, I think the foam core ended up being too flimsy for this size of a mold. I might have to start from scratch here. I just want to get this molded, because that Sculpey is already cracking and chipping in areas. Not a happy camper at the moment. Stay tuned...