The Simplicity Jig No. 1

John Harding introduces this jig for sharpening end mill cutters, the first of a series of related grinding accessories.

- John Harding

[Simplicity itself: be extremely easy to do (concise OED)]

Introduction

The feature of this design, photo 1, is to allow the cutter to be wiped across the grinding wheel leaving adjacent edges clear of wheel. The jig attaches to a sliding table with screw cross traverse for in feed.

Using a Stevenson collet block and ER collets to hold the cutters eliminates the need for machining. Except for the clamp pillars the jig can be made using only a bench drill and hand tools.

Construction

The main sub-assembly is of two pieces of angle bar bolted together, the upper piece being set to give a 2 degree back rake. This creates the concave end to the cutter.