Joined: Jul 07, 2012
|Posted: 2012-07-10 08:11 am  Permalink|
On 2012-07-10 06:17, AlohaStation wrote:
The 3D programs and printer should allow for more open space in you structure. Why are you making the recessed areas so shallow? ie: eyes of the skull, the inside of the mouth... What is the hole in the top for? Not trying to bust your chops just questions.
No problem! Thanks for the questions! If you can imagine a table printed layer by layer, and the first crosssection is the feet. Moving up and up and up, until the next crosssection is the flat top of the table. Imagine what would happen when you try to print this next layer with nothing under it - quite a mess with filament spilled into empty space and no support .
With a powder technology, where each layer is a layer of powder and the crosssection is built by solidifying certain areas of powder, then the un-solidified powder always acts as a support. But this is not the case for extruded filament printers.
So what we do with the table, is turn it upside down and print it from the top to the bottom. And also, in a pinch, we can gear the machine to actually print support. However, this can be a big waste of plastic, and also very hard to tear, pick, carve out of a model. If I'm gonna carve a model anyway, heck I might as well carve it out of wood
So this is why we try to avoid extreme overhangs. I can handle a little bit, and also I can handle picking off a little bit of support material. But if I were to go quite deep, like empty the mouth cavity, then it would not only be a pain to remove the support, but also compromise the integrity of the model's surface with roughened surfaces and the liklihood of breakage.
Hope this helps you understand!
Oh the hole in the top - funny you should ask that. Originally, the hole in the top was to create a sort of "woggle" situation, where the pendant could be threaded through the middle with a bead at the bottom. To make the pendant lie flat, I decided to add a hole through each side instead. The hole down through the center is a remainder of its history. But also - the hollower I can make a model, the better opportunity I have later for "polishing", if I so choose. I use a solvent to smooth the piece, and if the model is quite thick, the solvent seeps inside of it, essentially melting it from within. However, if it is more hollow, there is less chance this will happen.