Using a radius gauge on metal involves selecting the correct blade and fitting it precisely against the curved surface.
Radius gauges, also known as fillet gauges, are essential tools for measuring the radius of external or internal curves, often found on machined parts, molds, dies, and fabricated metal components. They typically consist of a set of blades, each precisely formed to a specific radius size.
Here's a breakdown of how to use a radius gauge on a metal surface:
Step-by-Step Guide
The process is straightforward and requires careful visual inspection and fitting.
- Locate and Identify the Curve: First, examine the metal object to locate the specific fillet or radius you need to measure. This is the curve you will be assessing with the gauge.
- Select the Appropriate Blade: Using the set of radius gauge blades, find the pin or blade that corresponds most closely to the fillet's size. Start with a blade that appears to match the curve visually, or try a few different sizes until you find one that seems close. The gauge set will have blades for various concave (internal) and convex (external) radii. Ensure you are using the correct type of blade for the curve you are measuring.
- Fit the Blade to the Curve: Carefully rest the pin or blade on the fillet so that it is flush with the fillet's surface and snug against its curve. For a perfect fit, there should be no visible gap between the gauge blade and the metal surface. If light passes through between the blade and the curve, the fit is not correct. Try different blades until you find the one that sits perfectly flush along the entire arc of the curve.
The size marked on the blade that fits without any gap is the exact radius of the metal curve.
Tips for Accurate Measurement
- Ensure the surface and the gauge blades are clean and free from dirt or debris, which can affect the fit.
- Hold the gauge blade perpendicular to the direction of the curve for consistent contact.
- Use a light source behind the gauge and the metal surface to check for gaps more easily. If you see light, the blade doesn't match the radius.
- For critical measurements, double-check the fit with adjacent gauge sizes to confirm that the chosen blade is indeed the best match.
Using a radius gauge is a manual process that relies on a good visual fit. Practice helps in quickly identifying the correct blade size.
