3D printing woes

I have had some successful prints over the last couple of months. I am happy with about %20 of them (two out of eight!). Gah. I am working hard to do three things.  One, create a workflow for my CADCAM II class next semester, two, make some work (conservative, production-type stuff) and three, learn some stone setting along the way.   

It might be super ambitious. 

I have never tested the mechanical accuracy of the metal through shapeways. I have always printed an object as a stand alone thing. It never had to fit another object or click into another object... until now. I have learned a lot. First and foremost, don't forget about shrinkage!  Remember if a piece is printed, cast, molded and recast you are talking at least %5 - %20 shrinkage. So all that time you spent modeling that ring to fit that stone goes right out the window. I actually successfully made a box clasp that works (needs some clean up) but.....it can't be molded because it will shrink and everything will be off. This just means that every clasp has to be printed together then cast which costs a hell of a lot more that molding. I will say that is has the perfect little click though. 

I will say that over the years the quality of the print/cast option has improved quite a bit. I actually had .8mm holes for my hinge and they all came out. I modeled in some slop in the hinge intentionally just in case but it turned out that I didn't need it. Unfortunately, I have to re-cut all of the seats to fit the stones because of shrinkage. Now that I have figured out both of those I am going to try to print a large bracelet with both a hinge and a clasp. Fingers crossed this might be a dud. 

Another pro-tip: even numbered stones tend to be easier to get than odd number stones. When I modeled these things I just threw a dart in it. 7mm stones look great! Right? Finding non-synthetic stones that large can be tough. You of course can get stones in any size if you can afford it.  It is way easier to get 6mm and 8mm than 7mm.  

Back to the computer for more modeling.  Fingers crossed!