Well I'm not one to give 3D advice, but I've been experimenting a lot with little swirls and printing rejections. I would suggest downloading netfabb for free and measuring the smallest parts of your model to make sure they line up with the 3D design rules - http://www.shapeways.com/design-rules/silver - 0.6mm. I've found the tapered part of my swirls often fallbelow that number leading to a rejection. You could redraw or thicken any parts that fall below that number and repop/remodel and you'll be set.
As cadula said you have to keep about the .6mm. Other than that you shouldn't have a problem with your designI learned a long time ago the wisest thing I can do is be on my own side, be an advocate for myself and others like me. -Maya Angelou
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