The steps in creating injection-mold parts usually go a bit like this:
1) A designer or company has an idea for a new product. It could be a simple, single-piece plastic part like a Frisbee, or something more complex like a mobile phone or car. Or something totally revolutionary like a modular wall bar :-)
2) The product might start life as a sketch on a napkin or in Playdough, but at some point the designer builds a 3D computer model/print a 3D version of the thing (or things). Here the designer establishes overall shape, structure, key features, and how parts will fit together, and plans how each part will be made.
3) The 3D file for each part is then sent to a manufacturer, who will make a tool to build it. The tool is usually steel and consists of two halves of a metal mold, with a hollow cavity in the shape of the part to be made. Melted plastic is injected into the cavity and allowed to cool. This is can be done hundreds, thousands or millions of times. Usually the part comes out of the tool completely finished and but sometimes it requires further finishing, like painting or plating.
4) The manufacturer builds the tool to the designer’s specification and tests it to see that the tool will make the parts as specified. The very first parts are called the FOT (First-Off-Tool) and it is rare that the parts are perfect the first time. Often the size or shape of the tool needs to be adjusted to make the parts fit perfectly, or the process needs to be adjusted. Sometimes the raw plastic needs to be injected into the mold at a slightly different temperature, pressure or speed, or the part won’t come out of mold quite right.
5) Once the parts are coming out of the tool the right way, the manufacturer gives the designer a few sample parts.
6) The designer confirms that they are in fact made to specification (correct size, shape, etc), and tests the samples for performance. Parts are tested for strength, durability, surface finish, colour etc. Sometimes there are changes that need to be made: sometimes the shape isn’t quiet right, or something is discovered during testing and a better feature or design solution is found. Tool changes are made and more sample parts are produced.
7) At this point, any flaws in the tool are fixed to resolve issues like part size or shape. During these trials the parts can be made from different materials to compare their performance.
8) Once the tool is producing parts that are in specification and they pass all the quality tests, the manufacturer does a pre-production run. This proves the tool and manufacturing process is capable of making lots of parts.
9) After a successful pre-production run, the tool and process is approved for mass production. Now you’re ready to make as many parts as needed.
We’re on step 4 in this process and we hope our Kickstarter campaign will put us over the edge to proceed. That’s where the support of our Kickstarter backers will come into play.