…code, cg, electronics, 3d printing…

Based on my previous post, I wanted to get better results from my sand-cast.  Things I learned from last time:

• Even though I had a split mold, the vertical edges caused the mold to tear-out during removal.  I have a feeling this is due to the ‘ridged’ sides the 3d-printing causes, making the walls ‘grip’ more.  Because of this, I adjusted my 3d model to have slightly tapered sides.
• The extruded text on my first model suffered the same problem as the above issue.  To resolve, I simply made the text extruded much less.
• The previous split mold only had one anchor point, in the middle, to join the two sides:  When connected it gave more yaw-play than I wanted.  The new version has two anchor points on either side.
• I watched a bunch of sand casting videos and read over multiple sites to make sure I got the sand cast itself created properly.

Based on all that, the end result turned out really nice:  Sprue cut off with saws-all, imperfections ground off with an angle-grinder, and polished with a Dremel:

Here’s a shot of it freshly pulled from the cast with the sprue still connected:

And here’s a shot of the 3d-printed two-part mold.  It took just under 4 hours to print on my Makerbot Replicator.  200 micron layer resolutoin, gray PLA, 220 deg C on a glass build plate covered in blue painters tape:

And finally, here’s a movie of the furnace just before it was time to pour:

I shot it with bare hands:  I got really hot, really fast 😉