Redesigning an Agricultural Injection Knife with Meltio Metal 3D Printing

In agriculture, equipment needs to withstand extreme wear and tough conditions. One critical component—the injection knife used in fertilizer systems—was falling short. S3 Industrial Solutions set out to improve its durability and longevity using metal additive manufacturing.

The Problem: Cracking at Stress Points

Traditional injection knives are typically made from solid steel via casting or machining. These blades cut into the soil and inject liquid fertilizer underground, but over time, the parts would crack—especially at high-stress zones—leading to replacements, downtime, and added cost.

The Approach: Redesigning for Additive

S3 re-engineered the knife specifically for additive manufacturing using the Meltio Engine CNC Integration system. Instead of sticking to the solid block design, they created a tubular structure that offered better strength-to-weight ratios and eliminated common failure points.

The new geometry wasn’t just lighter—it was smarter. With Meltio’s metal 3D printing capabilities, S3 could reinforce vulnerable areas, smooth out transitions, and create internal structures impossible with traditional methods.

The Outcome: Durable, Lightweight, and More Efficient

The 3D printed injection knife delivered several key improvements:

  • Longer lifespan thanks to reduced stress concentrations

  • Lower weight without sacrificing performance

  • Simplified production with fewer steps and materials

Because of the Meltio system’s ability to print directly onto metal substrates and its compatibility with existing CNC platforms, S3 could easily integrate the process into their workflow.

Printed in 15 hrs for $612, down from 10 weeks and $8,000.
Printed in 15 hrs for $612, down from 10 weeks and $8,000.

Why It Works

This project demonstrates the value of designing parts specifically for additive manufacturing. By pairing smart engineering with Meltio’s wire-laser metal deposition technology, S3 created a part that performs better in the field and is easier to produce.