Table of Contents
What is an undercut in machining?
In manufacturing, an undercut is a special type of recessed surface that is inaccessible using a straight tool. In turning, it refers to a recess in a diameter generally on the inside diameter of the part. In milling, it refers to a feature which is not visible when the part is viewed from the spindle.
Why is it not possible to create square internal corners on a milling machine?
This is because the cutting tool can access all aspects of the corner as illustrated below. However, square internal corners are impossible to create, as the path taken by the cutter will leave a certain amount of the corner inaccessible. This amount is determined by the radius of the cutting tool.
How do you get sharp edges off metal?
The three common methods are:
- Hand trimming. This uses specialized deburring tools which are like tiny knives you run along the metal edge.
- Filing, mechanical or rotary. Hand files are those flat blades with rows of tiny teeth.
- Sanding. This when abrasive paper is rubbed over the edge.
How do you make a corner in a CNC machine?
All you need to do is cut half the diameter of the tool further in one axis. Here’s an example: This is an undercut that balances the removed material on either side of the corner, and the result is an overall stronger corner. It takes a little bit more calculation for manual machines, but for CNC it’s extremely straightforward.
What happens when you machine a corner wrong?
Machining this difficult area with the wrong approach may result in: Generating an inside part radius that matches the radius of the tool at a 90° direction range is not a desirable approach to machining a corner. In this approach, the tool experiences extra material to cut (dark gray), an increased engagement angle, and a direction change.
Is there a way to make a sharp inside corner?
Since the tool needs to rotate in order to cut, there is no way for one of these styles of tool to make a sharp inside corner. While these square corners look great on paper (or a computer screen), they’re often simply not a good way to make machined components. Let’s look at some common alternatives.
What does it mean when cutting tool has inside corner?
One common and difficult situation is when a cutting tool experiences an “inside corner” condition. This is where the tool’s engagement angle significantly increases, potentially resulting in poor performance. Machining this difficult area with the wrong approach may result in: