Creating custom tools by 3D printing and casting
Creating custom tools by 3D printing and casting from Moshe Boruhin
Creating custom tools by 3D printing and casting

As part of a personal project, I developed a method for creating high quality low cost custom tool handles for people with hand related medical issues. The process consists of creating a silicone casting mold with a rotatable and interchangeable end unit (for fitting different tool heads) using a "positive" printed on a simple open source 3D printer. The reusable silicone mold is then used to cast thermosetting plastic handles.
This process has many advantages over simply 3D printing the handles:
• The cast plastic (I used G-26) has significantly greater mechanical strength.
• The material is non-toxic.
• The material is resistant to high temperatures (dishwasher safe).
• RepRap printed objects have internal cavities which can enable accumulation of filth and bacteria if used for cutlery handles, but cast handles are completely solid.
• Minimum 3D printer machine time - parts are printed only once.
• After the silicone mold is created the printed parts can be recycled.

3D printed “positive” for mold creation (yellow parts), RTV mold (pink parts) and final products. Won 1st place in - Creating Tomorrow's Products 2013, a competition held by the Reut institute focusing on creating products for handicapped people by using rapid manufacturing technologies.
CAD model
using 3D printed parts to make the molds for the RTV mold parts
RTV mold is ready
preparing to cast a knife
casting G-26
about 20 minutes after casting
end result
gLike
Creating custom tools by 3D printing and casting

As part of a personal project, I developed a method for creating high quality low cost custom tool handles for people with hand related medical issues. The process consists of creating a silicone casting mold with a rotatable and interchangeable end unit (for fitting different tool heads) using a "positive" printed on a simple open source 3D printer. The reusable silicone mold is then used to cast thermosetting plastic handles.
This process has many advantages over simply 3D printing the handles:
• The cast plastic (I used G-26) has significantly greater mechanical strength.
• The material is non-toxic.
• The material is resistant to high temperatures (dishwasher safe).
• RepRap printed objects have internal cavities which can enable accumulation of filth and bacteria if used for cutlery handles, but cast handles are completely solid.
• Minimum 3D printer machine time - parts are printed only once.
• After the silicone mold is created the printed parts can be recycled.

Moshe Boruhin
Industrial Designer haifa, Israel