5 Questions with Eric Schwarzenbach

1. What types of materials are used in grinding medical and orthopedic tools?
Most medical machining tools are made of stainless steel with a small number made of high-speed steel. Scalpels are often produced with ceramic materials. Carbide is typically used for implants, screws, heart valves, or stents. Nickel titanium, often used for dental files, is prone to extreme elasticity because it’s a memory material.

With many applications, grinding requires support steadies with the exact opposing shape of the tool blank. And, because ceramic is such a brittle material, machine rigidity in the tool grinder is necessary for perfect concentricity.

2. What requirements are often overlooked in grinding medical and orthopedic tools?
Toolmakers sometimes forget the importance of tool blank conditions. Most tool blanks come to the factory non-straight and aren’t usable until they’re reground on cylindrical grinding equipment. Without proper blank preparation when grinding, tool runout will be too high, and tool life won’t suffice.

3. How important are support accessories in grinding?
In buying a new house, when some say “location, location, location” it drives a great buy. In grinding medical or orthopedic tools, it’s about “tool support, tool support, tool support.”

Proprietary steady rests and V-block shank guidance on tool grinders help alleviate part warpage due to heat treatment. Tool support also eliminates curvature problems caused by extreme length-to-diameter ratios on smaller tools.

4. What special tool grinder features support medical machining?
Cutting tools are often made in large production batches to keep costs down, so automation is paramount. Repeatability between production runs, where a good tool can be correctly set up once all subsequent tools are of the same quality, is vital. Long-run batches are also effective when there’s reliability, repeatability, and thermal stability on the machine between each production run. Automation systems can include custom-developed step loaders. Horizontal stacking parts feeders for long, thin blanks can be designed.

Pick-and-place loaders can also offer consistent tool handling. A tool-loading system that is vertically stacked alongside a multi-axis robot system offers a maximum range of tool production applications.

Workholding solutions can include oversized gripping collets for stepped medical parts, quick-disconnect shank-end tool types, or other oddly shaped parts.

Efficient ergonomics in machine setup between different tool production runs are also important. Small footprints and thermal stability support 24/7 unattended production and long machine life.

5. What are special software needs in medical tooling?
A quality software package would include intuitive programming interface, integrative 3D prediction capabilities, and the ability to work offline. All-in-one software with tool application types and updates for life can meet users’ needs for a lifetime.

Good software can program standard, high-performance tools and specialty tools without additional options or add-ons.

Powerful, stable, and fast tool simulator produces 3D imaging for tool and machine simulations. The ability to track machine movements before grinding reduces setup time, enables quicker verifications, and avoids collisions.