Hobby CNC Routing

Chapter 1: How to Use This Workbook: A Bench Reference for Real Cuts

You've got a new spindle, or maybe a used machine that needed a new controller, or perhaps you've finally pulled the trigger on that 2.2kW water-cooled kit that's been sitting in your cart for six months. The machine is trammed, the wasteboard is surfaced, and you've got a piece of 3/4" birch plywood clamped down. You fire up your CAM software, pick a 1/4" end mill, and the software asks for a feed rate and a spindle speed. You type in something you half-remember from a forum post. The tool plunges in, and within three seconds you hear that telltale high-pitched squeal, or worse, the machine is shaking hard enough to walk across the bench, or there's a puff of smoke and the bit is glowing red.

This book is the antidote to that moment. It is not a theory textbook, and it is not a collection of vague "start slow and increase until it sounds right" suggestions. It is a bench reference, designed to be opened flat, spattered with cutting fluid, and consulted while the spindle is still spinning down. Every table in this book gives you a specific number to start with: a chip load in thousandths of an inch per tooth, a spindle speed in RPM, a feed rate in inches per minute. You will still need to listen and look, but you will be listening and looking from a starting point that is