[3D Printing Knowledge] Application Guide to Creating Thermoforming Templates in FDM 3D Printing

Thermoforming templates can be fabricated using various methods, including fused deposition modeling ( FDM ) 3D printing. In the previous two articles, we explored the technologies, advantages, and applications of SLA and SLS in the manufacture of thermoforming templates.

Click here to view related articles:
1) Application Guide for Creating Thermoforming Templates with SLS 3D Printing
2) Application Guide for Creating Thermoforming Templates using SLA 3D Printing

In this article, we will explore in more detail the advantages of using filament 3D printing to create thermoforming stencils. We will also provide best practices and helpful tips. By understanding the potential of this technology and its applications in the thermoforming industry, you can make an informed decision about choosing the most suitable stencil manufacturing method!

Just like the previous two articles, the first thing to do is to introduce what this technology is!

What is wire 3D printing?
Wire 3D printing is an additive manufacturing technique that uses continuous filaments of thermoplastic material to create 3D objects. The process involves melting and extruding the material layer by layer, building the object from the bottom up.

The technology behind 3D printing of wire is called FDM (Fused Deposition Modeling) or FFF (Fused Wire Fabrication). Today, these two terms are used interchangeably because they refer to almost the same manufacturing process.

Compared to other additive manufacturing technologies, FDM parts can be produced faster and at a lower cost, but the quality and performance vary. FDM 3D printers are also compatible with a wide range of materials, enabling their broad application.

Design and manufacture of thermoforming templates
The following are some points to note and suggestions for designing and manufacturing thermoforming templates using filament 3D printing.

floor height
As with all 3D printing technologies, the thinner the layer, the smoother the surface. For thermoforming stencils manufactured using filament 3D printing , we recommend a layer height between 0.1 and 0.2 mm to create a stencil with a subtle, layered texture. This will significantly improve the demolding experience.

If you are creating a large prototype template without vertical walls, you can increase the floor height, but it is always recommended to test.

Template draft angle
We recommend a draft angle of at least 5° for optimal molding and demolding results. However, stencils made using filament 3D printing have more surface texture, making demolding more difficult compared to stencils with smooth surfaces. If increasing the draft angle is not possible, consider sanding or smoothing the stencil surface before molding.

Nozzle diameter
Most filament 3D printers come with a standard 0.4 mm nozzle . If you need to create small stencils with high precision or small design features, you can use a 0.25 mm nozzle. However, if you are creating large, simple stencils, you should consider upgrading to a larger 0.8 mm nozzle. This will make your 3D printing faster and the stencils you create more durable.

shell thickness
Large, hollow molds are prone to deformation during molding under pressure and heat, especially when using powerful pressure molding machines like multipliers. To increase mold strength, we recommend fabricating a mold with an outer shell thickness of 3-5 mm , ideally testing with different thicknesses to find the optimal one.

When fabricating thermoforming templates, the thickness of the top portion plays a crucial role because it has the longest contact time with the thermoplastic sheet. Increasing the thickness of the top portion to match the vertical wall thickness can prevent deformation due to pressure and heat.

Fill density
Higher filler density results in greater wear resistance for the parts, making it the best choice for any project. A filler density of 50% is recommended, but testing is strongly advised first.

High filler density ensures that parts have sufficient strength to withstand pressure and heat , and also ensures that parts can be reused, making them ideal for projects that require extensive testing.

Pore ​​size
We recommend using tapered vents , with a diameter not exceeding 0.4 mm on the template surface and not exceeding 2 mm at the bottom of the template.

Using larger nozzles and composite materials may slightly affect the tolerances of a 3D printer. Therefore, we recommend testing your 3D printer to ensure that the vents are not blocked when printing using standard settings.

Draft shield
When using engineered materials for 3D printing to create thermoforming templates, it is recommended to add a wind shield when preparing the 3D printed model. This will help reduce warping and ensure better overall part quality.

Recommended cable materials
When using 3D printing with wire to create thermoforming templates, we recommend using engineering materials such as Ultimaker nylon, which have high thermal stability, high heat distortion temperature and high tensile strength.

While thermoforming templates made using other filament materials (such as ABS, PETG, or HIPS) are compatible with Mayku's 3D molding machines (such as the Mayku FormBox ), they are often best suited for early prototyping. However, the final template should be made using engineering materials, as they offer superior mechanical properties.