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REDRESSING
INSTRUCTIONS
The redressing and reshaping of tools having chipped battered
or mushroomed striking or struck surfaces is not recommended.
When a tool has reached this stage through normal use or abuse,
it should be discarded.
There are three basic rules which apply to the redressing of
dull cutting edges:
- Rigidly support the tool being redressed.
- Use a hand file or whetstone only, never a grinding
wheel. File or stone away from the cutting edge.
- Original contour of cutting edge should be restored.
Axes. Use a hand file for redressing. Start 2 or 3 inches
back from the cutting edge and file to about Ѕ inch from the edge.
Work for a fan shape, leaving reinforcement at corners for strength.
File the remaining Ѕ inch, blending into previously filed area
preserving the original contour of the cutting edge. Remove all
scratches with a whetstone or hone Ѕ inch back from the cutting
edge. See cross section C illustration below for the "right" way
to shape the edge in redressing axes. Other illustrations show
"wrong" ways to redress axes.
Hatchets. Hatchets with double bevels should be redressed
as illustrated in A below. Hatchets with single bevels should
be redressed as illustrated in B below. Use a hand file for redressing,
removing scratches with a whetstone.
Cold Chisels (Flat). Cold chisels are hardened on the
cutting edge. Redressing may be done with a hand file or whetstone
restoring to original shape or to an included angle of approximately
70 degrees (see illustration below).
Other Machinists' Chisels. Other commonly used metal-working
chisels are Round Nose, Diamond Point and Cape. Redressing instructions
are the same as for flat cold chisels except that bevel angles
are approximately as illustrated.
Hot Chisels. These are handled tools used for cutting
hot metal. Redressing instructions are the same as for cold chisels.
Punches. The working end of pin and rivet punches and
blacksmiths' punches should be redressed flat and square with
the axis of the tool. The point of center punches should be redressed
flat and square with the axis of the tool. The point of center
punches should be redressed to an included angle of approximately
60 degrees; prick punches, to an included angle of approximately
30 degrees.
Bricklayers' Tools. Bricklayers' tools should be redressed
to approximately the angles illustrated.
Woodchoppers' Mauls and Wood Splitting Wedges. The instructions
for redressing axes apply also to these tools, although they have
heavier heads and thicker sections in the bit. Hand file the splitting
edge to an included angle of approximately 70 degrees. See cold
chisel illustration for 70 degree included angle.
Star Drills. Hand file all cutting edges; to an included
angle of approximately 70 degrees. See cold chisel illustration
for included angle of 70 degrees.
Prospecting Picks. Redress with a hand file to restore
original contour of the pick end.
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