The 3 tools that come in the Maker Kit are helpful tools for learning the design principles of the thermoforming and the FormBox as they include undercuts, draft angles, and air holes.
Here are a few of the best practices for designing a tool for thermoforming:
The size of the FormBox bed is 200mm x 200mm. The maximum width and length you are able to mold is 150mm x 150mm. To avoid tearing the plastic, we suggest not vacuum forming anything taller than it is wide.
As a general rule, undercuts should be avoided. If you form a model with ledges or indentations, you won’t be able to remove the tool once the plastic sheet cools down. An exception to the rule is when forming with Mayku EVA Sheets — in this case, you can use tools with small undercuts, as well as embossed text on vertical walls due to the flexibility of the EVA material.
Undercuts should be avoided where possible as they can restrict demolding and cause materials to overstretch. If your design requires undercuts, consider creating a tool consisting of multiple slotting parts to help release the formed part.
A draft angle is a slant that is applied to the faces of your model to enable easier release of a tool from a plastic sheet. The greater the draft, the easier the de-molding process. It also helps to achieve uniform sheet thickness. Specifically, we recommended a minimum of a 5° draft angle to achieve the best possible forming and tool release.
Rigid materials (e.g. Clear Sheets (PETG), Form Sheets (HIPS) = 8° draft angle
Flexible materials (e.g. Flex sheets) = no draft angle required
