I decided I needed to build myself a "DAIR" ... or at least a "SAIR" robot ... so I began designing parts based on using hobby servo motors ... they're everywhere and it is easy to program a Parallax BOE or HomeWork board or BS2 Stamp 2 module ... so I came up with a few ideas.
Step 1: A Better Design ...
After puttsing around looking at different 3D Plastic printers I got a 3D Touch ... it's pretty neat but quickly I found that designs for injection mold don't work so well for 3D plastic printing and so I had to begin redesigning my DAIR robot parts for 3D printing. During this task I began to redesign the robot itself, simplifying the design and reducing the number of parts needed to build a Home Hobby Dual Arm Industrial Robot.
Now I"m saving material and that means I'm saving cash!
Step 2: Designing to stick together ...
After a few truly failed attempts to get some parts printed I found I had to add "fillets" between surfaces ... fillets are the smooth rounded surfaces that look like weld lines but are just filled-in material to create a stronger joint. In the case of 3D printing it helps to hold perpendicular surfaces ... such as horizontal to vertical. It also makes the robot look more professional anyway.
Step 3: Complex Geometries ...
Complex geometries was the next issue and the next bunch of images show the failures and the compromises it takes to get a robot part printed.
These images show my compromised choice ... the extra threads inside can be cut out of the way but the part will function as needed because the exterior shape fits the robot design.