Angular milling or angle milling is a CNC milling operation that involves machining a surface at an angle with the angle milling cutter. Today, we’ll get into the basics of angle milling and the cutting tool, more importantly, there are different ways you can refer to for how to cut angles on a milling machine.
Angle milling, also known as angular milling, refers to the process of milling flat surfaces that are neither parallel nor perpendicular to the axis of the cutting tool, which means the surface to be machined is at an angle to the axis of the revolving milling cutter. The angular groove can be single or double angle, and varying according to the type and contour of the angular cutter used.
There are two types of angle cutters including single angle milling cutters and double (equal) angle milling cutters. Single angle cutters have teeth on the conical or angular face of the cutter and on the large flat side. A single angle cutter is designed for milling dovetails, chamfering or beveling parts and manufactured in single right and left angles at 45° & 60°. Double or equal angle cutters have v-shaped teeth with both conical surfaces at an angle to the end faces, used for milling threads, v-grooves, serrations, and other angular surfaces. Double angles are generally supplied in 45°, 60°, & 90° angles.
If you want to mill an angle on a metal plate when the milling machine does not have a tilting head. A sine plate can be used, but it takes up a fair bit of vertical room and requires a set of gauge blocks to prop it up with, you also need to know how the sine function works and make use of it. How to mill angles or how to cut angles on a mill? Instead of using a sine bar, you can figure out the vertical deviation over a known distance and set up with a plunge indicator or those fin angles, probably don’t need to be at a perfect set angle, just eyeball it on a standard bevel protractor. If your bevel protractor is small enough, you can set it on the bottom of the vise and rest your workpiece right on the blade. Do not adjust the protractor and do the same to flip the part to the other side.
Here is a video from Youtube shows the technique for how to set a super accurate angle without expensive sine bar or gauge blocks, it is precise than you would get using a protractor and a scribe. Suitable for cutting an angle on a part in a mill and do not have angle gauges.