Compared with traditional processing methods, 3D printing is one of the fastest developments in recent years and is becoming increasingly convenient and economical. Many key factors play a role here. For example, material factors, printing technology, model file resolution, wall thickness, etc. an inadequate wall thickness will frustrate you.
How thick is the wall?
Wall thickness is a very important concept in 3D printing. Wall thickness is the distance between the inner and outer surfaces of the model. The minimum wall thickness directly determines the thickness of the printed object and even determines whether the object can be printed. Proper wall thickness can bring many benefits, including optimizing the structure, saving costs, preventing various accidents, etc. It can not only perfectly represent your project but also lead to better work performance.
Why should you pay attention to the correct wall thickness?
Thicker wall thicknesses are undoubtedly a better choice for parts in some particularly heavy operating environments. However, reducing wall thickness appears to be more cost-effective, and the benefits of reducing wall thickness can be even more significant if the function and strength of the part are not compromised. For example:
1. Save printing time and costs by enabling faster cooling and achieving higher production rates.
2. Deformations caused by the cooling process are largely avoided.
3. Lighter weight allows for easier transportation and handling.
Note that when it comes to the wall thickness of the part, thinner is better does not apply. Instead, the best choice is to reduce unnecessary wall thickness according to the structure and shape of different requirements, taking into consideration the printing effort and part requirements, while ensuring its functionality.
The consequences of inadequate wall thickness
3D printed parts often have thin walls that bend and parts that deform, either because the walls are too thin or because support structures are not used to hold the part in place during the printing process. Because printers work layer by layer, it is important to ensure that the layers are in stable contact with each other and have additional support during the printing process. Just like building a building, we need concrete to be firmly bonded and rebar to support it.
(1) Deformation
Deformations are related to the printing process. The bottom corners of the object appear curved upward. The light deforms the object and the heavy material causes the object to fall during the printing process, causing the printing process to fail completely. The cause of the warping is the shrinkage of the printing material as it cools after exiting the high-temperature nozzle. If the shrinkage around the large object is greater during printing, deformation will occur. ABS material shrinks more than PLA, so printing large objects with ABS is very difficult.
(2) ripple
Waviness is a common problem in 3D printing. It is due to the principle of thermal expansion and contraction of printing material. This causes the model and print bed to more easily deform at the bottom edge or even lift off the bed. The smaller the impact on the printing effect, the more serious the deformation of the bottom of the model and the more serious the printing error.
Choose a uniform wall thickness
A uniform wall thickness is very important for the 3D printing cooling process. When parts with large differences in thickness are joined together into certain oversized parts, these parts can warp, crack, warp, or even deteriorate during the cooling process. To avoid the effects of tension and shrinkage, a constant and uniform wall thickness is the best choice. Even though constant wall thickness cannot be guaranteed, a gradual overshoot of wall thickness is a good approach.
4 Factors to Consider When Designing Wall Thickness
(1) Materials
Each material has its inherent properties, they are brittle, strong, shiny, rough, light, heavy and so on. Different materials have different design principles.
Different materials use different printing technologies, ABS/PLA uses FDM; Nylon, aluminum uses SLS; The resin uses SLA or DLP. Different printing technologies create different surface effects. There is a point where the print size of printers with different printing technologies is not the same, and the post-processing methods for printing are different, some complex, some simple.
(2) Working environment and product function
Are there high temperatures and high humidity in the product's working environment?
Will the product be exposed to sunlight and wind for a long period of time?
Does the product need to work in a high-stress environment?
Does the product need to be transparent or have good optical properties?
Does the product require a specific color, be it the color of the material itself or a color obtained by spray painting?
(3) Product design
The shape and size of the product, reinforcements, rounded corners, chamfers and transitions are all determined by the wall thickness. The wall thickness of the product depends on the final requirement of the product and the external force that the product needs to withstand, whether it is subject to pressure from other parts or needs to be used as a supporting part for other parts. Wall thickness is determined based on the initial design of the product to simulate the scenario in which it actually operates, the weight, characteristics, electrical properties, stability, dimensional accuracy and assembly requirements of the final product.
(4) Costs
A thin wall is the most material-saving option, but it can also be the most expensive because there is a high chance that the object printed to save material will fail. Redrawing and printing not only wastes more material but also wastes valuable time. Designing and printing the wall thickness of an object based on its size, capacity and working environment is undoubtedly the best option if the ideal wall thickness can be determined based on this.
