I am trying to establish a good workflow for producing puppets quickly, and have started looking at using a 3d printer to create a figure, then mold it in hydrocal, then cast the puppet in foam latex.
My concern is that, because I plan to produce human forms (which inherently curvy), that the printed model's stair-stepping nature would be reflected in the mold, and thus the final puppet.
I've provided a picture below to illustrate what I mean by "Stair-stepping". The model of the car was printed on a printer with up-to 100 micron resolution, so I am assuming the model was produced at 100 microns. The other picture shows a man's thumb next to a 20 micron print.
My questions are... Would smoothing the stairs-stepping with a fine Dremel tip, or even sandpaper be a viable solution? Is it possible to tweak the mold (made of ultracal or hydrocal) by sanding it instead of the figure that is molded? Is it possible to get prints out of a machine in the 800 dollar range (or cheaper), that are high enough quality to mold and cast without too much of this stair-stepping? do you think its possible to get good enough detail out of the prints to allow them to be cast? Does anyone have any experience with this? Is this do-able with 100 micron resolution or would i need a 50 or even 20 micron res?
Sorry for all of the questions, thanks in advance to everyone!
You probably want to check out acetone vapor baths to smooth out your prints if using ABS. You will not be able to preserve overly fine details as what you are doing is dissolving the plastic and having it reflow into the layer seams. You could also look into a product called XTC-3D from Smooth-On and is a resin the is self leveling and wets the surface and fills the gaps in a similar way as the bath does. Getting general and bulk forms work very well this way. To really get smooth finishes in 3d printing you usually need to go the UV laser resin systems but you are usually limited to a fraction of the volume you could do with PLA/ABS methods. Another option is to make a mold of your rough item in silicone and going the toy wax route and finishing the smoothing and details that way and making your final mold from that part.