This document discusses sharpening tools like chisels and planes. It explains that grinding is used to reshape a blade when it is worn down, damaged, or incorrectly sharpened. Sharpening involves using sharpening stones like an oilstone or honing stone to hone the blade back to a fine cutting edge. The correct grinding angle is 25 degrees while the sharpening angle is 30 degrees. Sharpening saws involves filing the teeth level and using a saw set to bend every second tooth to ensure the blade cuts properly.

1. WOOD
MATERIALS TECHNOLOGY
4th Edition

2. Chapter 20
Sharpening Tools

3. Sharpening − chisels/planes
Procedure
Grinding
Sharpening/honing
Backing off
(remove the burr)
 Grinding
 Sharpening

4. When to grind?
You grind the blade when
 It has worn down
 It has been damaged
 It has been rounded over
by incorrect sharpening

5. Sharpening process
− Sharpening stones

6. Sharpening angles
 Grinding angle
– 25 degrees
 Sharpening angle
– 30 degrees

7. Sharpening − saws
Process
 Hold saw in the vice and
file the teeth level
 The teeth are reshaped
to a fine point using a
triangular file
 Every second tooth must
be bent (set) to the side
using a saw set

8. Quiz

9.  Name the piece of sharpening equipment in the pictures
below
− Slipstone
− Oilstone/honing stone

10.  What are the correct angles associated with sharpening
the blade of a plane?
Grinding
angle
25°
Sharpening
angle
30°
25°
30°

11.  Name this tool and describe why it is important
 Sawset
– The sawset bends every second tooth of a saw to one side
– This ensures that when the saw cuts a piece, the blade does not get
stuck in the groove or kerf

12.  What is used to lubricate this sharpening stone?
 Oil is used to keep the
stone lubricated and to stop
the stone getting clogged