How to create an injection mold on STL data
STL machining the mold for the JDgear 'Bug' hat lightCompany JD Gear Idaho Falls, USA. produces small lights using the motto "Defeat Darkness". These lights can be clipped on a hat (hence they are called Hat light), and look a bit like a large bug: hence the name "BUG".
The light contains a small battery, a LED light, some wires and a switch. Typical target use is during outdoor sports like fishing, hiking and camping.
the hat light to be produced, and its CAD design in Rhino.
The mold for this Bug has been created by Molds Direct (later called Epiphany Plastics) in Salt Lake City, USA), using DeskProto. The geometry for this product has been designed using the Rhino 3D CAD software, and transferred to DeskProto as high-res STL file. As the accuracy of the STL file to be written can be freely chosen, it is easy to make the polygon model in the STL file accurate enough for moldmaking.
The two halves of the mold: cavity and core.
Two separate parts need to be molded for this product: the right half and the left half, which after placing LED, battery etc can be clicked together. The mold contains two cavities, to produce the left and right part in one shot. The pictures clearly show the differences between the two mold halves:
- the top half contains the cavities. These are created by EDM machine (spark-erosion) using a DeskProto machined Electrode, and afterwards are polished for a high quality product surface.
- the bottom half (shown right) contains the core. The core is directly machined in steel: the toolpath marks still are clearly visible.
The resulting product, ready for sale, and a promotional flyer.
The illustrations above show that the resulting hat-light is a handy and attractive gadget.