1. What is Grafting Printing?

Mold grafting printing is a hybrid additive-subtractive manufacturing method where pre-formed mold parts are used as a base, and 3D-printed components are “grown” on top of the base. The already-formed parts are usually made using traditional manufacturing methods, typically from standard mold steel. The printed parts are formed using 3D printing technology, with materials specifically designed for 3D-printed molds. By combining these two materials into one integrated part, it is referred to as grafting printing.

Grafting printing is very popular among mold users who adopt 3D printing technology, primarily due to its economic advantages. In the mold industry, the common practice is to quote 3D printing costs based on weight; the heavier the print, the more expensive it is. Therefore, how to reduce printing costs while still benefiting from the advantages that 3D printing brings to molds is a common concern for industry users.

2. Advantages of Grafting Printing

In this context, grafting printing has emerged as a more cost-effective solution. By using grafting printing, large base sections that do not require conformal cooling channels, venting, or molding surfaces can be machined traditionally, while the sections that need conformal cooling channels, venting, or molding surfaces can be 3D printed and directly “grown” on the base, forming a complete mold component. This clever application avoids printing large solid sections, reducing both printing time and costs while allowing complex conformal cooling and venting structures to be integrated into the mold. This results in improved quality, increased efficiency, and reduced costs.

However, to successfully apply grafting printing in such hybrid manufacturing processes while ensuring mold longevity, higher standards must be met in terms of printing manufacturing processes, materials, and production quality control.

3. How to Ensure Effective Grafting

Firstly, it is essential to ensure compatibility between the printing material and the base material, meaning the compatibility of the metal printing powder with the traditional mold steel base. The greater the compositional difference between the grafted part and the base material, the more likely it is that excessive elemental diffusion or abnormal precipitation will occur at the bonding interface, leading to insufficient bonding strength, poor toughness, abnormal inclusions, or poor fusion. This could result in mold cracking or water leakage. Therefore, when using grafting printing, it is recommended to use printing materials and grafting techniques specifically developed for mold steel to achieve better compatibility.

Secondly, precise alignment between the base and the printed parts is crucial. Whether the base is machined by the customer or the printing service provider, it must meet the precision standards required for printing. For laser alignment during printing, various methods are used, including manual calibration, auxiliary light alignment, or machine vision alignment. Regardless of the method, the goal is to achieve error-free grafting with minimal deviations, ensuring the effectiveness of the grafting process.

Compared to full 3D printing, grafting printing offers more significant cost-effectiveness and represents a technological innovation that deeply integrates 3D printing with mold applications. It perfectly meets the current market demand for advanced manufacturing technology at lower production costs.

LAMOTEK has been deeply involved in mold 3D printing for many years, accumulating extensive innovative experience and numerous application cases in dedicated printing materials, grafting printing processes, post-processing of grafted components, and production quality control. We provide highly cost-effective, reliable, and practical 3D printing solutions for mold users.