ART
BEAUTY & WELLNESS
CRAFT
CULTURE & HISTORY
ENTERTAINMENT
ENVIRONMENT
FOOD & DRINKS
REVERSE ENGINEERING
SCIENCES
SPORTS
TECHNOLOGY
WEARABLES
Rasps: Teeth Raised One at a Time with a Pointed Punch
Forge

Created by

Forge

11. October 2026NO
1
0
0
0
0

Rasps: Teeth Raised One at a Time with a Pointed Punch

A rasp is a coarse file whose teeth stand separately instead of in continuous rows. Each tooth is raised by driving a pointed punch into the face of the blank at uniform distances. Because the teeth stand apart, a rasp clogs less than a cut file on soft material such as wood or a horse's hoof. The blank is forged, annealed and ground like a file blank, and the finished rasp is hardened like a file: coated against scale, brought to a dull red heat and plunged into water, with the tang tempered so it will not snap. Machine-made rasps have uniformly stamped teeth, which line up row behind row and leave deeper marks; slightly uneven hand-cut teeth avoid this.
Advanced
2 days (annealing overnight)

Instructions

1

Forge the blank

Forge the steel to a tapered bar, flat, round or half-round, with a narrow pointed tang at one end.

Materials for this step:

High-carbon Steel BilletHigh-carbon Steel Billet0.5 kg

Tools needed:

Blacksmith ForgeBlacksmith Forge
AnvilAnvil
Forge HammerForge Hammer
Forge TongsForge Tongs
2

Anneal and grind

Anneal the blank soft so the teeth can be raised, then grind the faces to a smooth, clear surface.

Tools needed:

Blacksmith ForgeBlacksmith Forge
GrindstoneGrindstone
3

Punch the teeth

Drive the pointed punch into the face with the hammer at uniform distances, raising one separate tooth at each blow. Turn the rasp over on a soft metal plate to work the other face without crushing the finished teeth.

Tools needed:

Rasp PunchRasp Punch
Forge HammerForge Hammer
AnvilAnvil
Pewter PlatePewter Plate
4

Harden

Coat the toothed surface thickly with a salt composition against scaling, raise the rasp to a dull red heat in a clear coke fire and plunge it upright into water. If it bends, straighten it across a fulcrum before it is fully cold.

Materials for this step:

SaltSalt1 kg
Metallurgical CokeMetallurgical Coke1 as required

Tools needed:

Blacksmith ForgeBlacksmith Forge
BucketBucket
Forge TongsForge Tongs
5

Temper the tang and clean

Temper the tang by dipping it in molten lead so it will not snap. Scour and wash off every trace of salt, then brush the rasp with oil.

Tools needed:

Molten Lead BathMolten Lead Bath
Forge TongsForge Tongs

Materials

3

Tools Required

9

CC0 Public Domain

This blueprint is released under CC0. You are free to copy, modify, distribute, and use this work for any purpose, without asking permission.

Support the Maker by purchasing products through their Blueprint where they earn a Maker Commission set by Vendors, or create a new iteration of this Blueprint and include it as a connection in your own Blueprint to share revenue.

Discussion

(0)

Log in to join the discussion

Loading comments...