ROBOTIS (DARwIn) -OP 3D printed brackets in Steel.

I printed out the hip bracket / frame number 13. I printed in steel for many reasons. The hip bracket is the most critical bracket on the OP and it's weak spot. As you can see in the pictures below it printed out very well! It is a very strong bracket with little chance of breaking. The only issues are that it is a expense process and the bracket cost reflects this. Plus the bracket is too heavy to make the whole robot in steel.

Link to Shapeway's steel information webpage.

"To build steel models, special 3D printers deposit small drops of glue onto layers of stainless steel powder, one layer at a time, until the print is complete. We carefully remove these models from the printer. At this stage of the process, the objects are very fragile, similar to wet sand. The models then go through an infusion process that replaces the glue with bronze, creating a full metal product. Models are then processed to achieve your desired finish, sprayed with a sealant, and shipped to you."

Where you can buy the bracket. 

Weights of the part printed in different types of materials.

Nylon:

Steel, as you can see it is very heavy:

Metallic Plastic:

Closer look at the part in 3d printed steel.