We are entering a new phase in foundry mold and core production. Soon 3D printing will be commonplace, phasing out traditional core making. 3D printing needs no pattern to produce dimensionally accurate cores and molds quickly. They can be made from various media and binders. The binder percentage can fluctuate depending on the parts needed physical properties.
3D printed parts are available direct from Voxeljet in Canton, MI. Present your Carpenter Brothers, Inc. salesman with an STP file of the core or mold you need to be produced. They can quickly get you a quote and lead time. Usually, the lead time is less than a week from receiving the file. Voxeljet will then produce the part and ship it to your location. Sand parts can be printed in furan or phenolic binder systems. An inorganic binder system is in development.
PMMA parts are for investment foundry applications. It replaces the wax pattern used by investment casters. Once the part is printed from the customer’s file, it can be cleaned and waxed and then shipped to the foundry for coating. The foundry applies the refractory coating in layers building a shell. Once the required shell thickness is achieved, the foundry can flash out the PMMA pattern. This is done quickly with a touch-like flame. No autoclave is necessary. The pattern will completely vaporize leaving little to no ash residue.
Printing Machines come in assorted sizes depending on production needs.
The printing process involves a thin layer of sand being laid down on the workbox bed. The print head then dispenses the binder exactly where the program dictates. The workbox bed is then lowered, another layer of sand is laid down, and the process repeats until completion. The 3D printed mold or cores can be removed from the workbox almost immediately. Further processing (placing the parts into a low-temperature oven for final cure) may be needed should higher tensile be required.
Voxeljet USA manufactures 3D printers in Canton, MI USA. They specialize in Phenolic Binder Printers. These printers utilize a 1-part printing binder. High tensile and part integrity is achieved using these printers.