Noob

I'm gonna bite the bullet here, let myself look like a total noob and ask some beginner questions of a general nature. If you take a look at my Hidden Hearts pendants, that may help.

1) I make my designs in SketchUp (the free version). No matter what settings I use for dimensions and scale, arcs and circles are rendered as straight-line segments. I send the designs through netfabb and then to Shapeways.

So when the items are 3D printed, they also don't have actual arcs and curves. Is this because of the inherent limitations of the SketchUp program? Can I do anything about it?

2) I also don't understand if there is a point at which a design goes from being cast as a 'solid' item- such as the HH pendant- to one that needs to be altered to get the required minimum wall thickness, OR altered so that it ISN'T a solid casting, to save material costs.

(Up until today, I had a larger printed Ceramic pieces of both the solid and open HH design for sale on my page. They measure about 4" x 4" x 1-1/2". I took them off while the new ceramics thing settles down.) My point is that I struggle with the wall thickness thing too much and I don't know why.

Thanks for your help.

If I understand your question right, this might help:
http://stonysmith.com/wired/scaling.asp

That writeup is a little off your topic, but the point is.. at this time, 3d printers work with objects made out of triangles. That means that models are going to have "flat spots", unless you make your triangles very very tiny. In Skechup, you need to increase the number of facets to make things smoother.

As to hollowing, that's another topic entirely. <grin>

Hey Ken,

These are common questions, so no harm in asking!

Regarding arcs and circles in Sketchup, you can increase the # of line segments they are made of, so that the arcs look smoother when printed. I cover this in more detail in the 4th tip of this blog post. Here is a video if that helps as well.

Regarding wall thickness, you can hollow out a part if the overall thickness is greater than 2-3x the minimum wall thickness. Just be sure to leave an escape hole for the support material to be removed if you do hollow the part.

Does that help?

Thanks very much!

Feeling a bit less noobish!