Page 120 - My FlipBook
P. 120
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88 INSTRUMENTS AND APPLIANCES
4. Carborundum stones and chuck for lathe
5. Arkansas stone
6. Anvil
7. Hammer
8. Metal file
9. Instrument gauge
10. Felt cones and brush wheels for lathe
1 1 Emery paper and polishing powders.
Directions for Making Steel Excavators and Chisels
1. Annealing.—Select the blank of proper size and with
the blowpipe or Bunsen burner heat the point and shank to
full cherry red and allow to cool slowly. This anneals it and
makes it soft and pliable.
2. Place the instrument to be duplicated, or a picture of
it, together with a memorandum of its formula, before you.
3. With the millimeter gauge see if that portion to be made
into the blade will need any change in form or dimensions; if
so, procure the needed change with hammer and anvil or the
file.
If necessary, file the shank down to the proper measure-
4.
ment and taper.
5. Angling.—Bend the shank by means of the pliers till
the proper angles, as mon-angle, bin-angle, triple-angle,
contra-angle, etc., are procured, as indicated by its formula,
verifying them with the instrument gauge and by comparing
with the model to be duplicated.
6. Beveling.—File the cutting edge of the blade to the
proper bevel, verifying all dimensions with the millimeter gauge.
7. Preliminary Polish.—Remove all file marks with fine
emery paper, then take to the lathe and give a high polish,
first using pumice on a felt cone or wheel and later whiting
and water.
88 INSTRUMENTS AND APPLIANCES
4. Carborundum stones and chuck for lathe
5. Arkansas stone
6. Anvil
7. Hammer
8. Metal file
9. Instrument gauge
10. Felt cones and brush wheels for lathe
1 1 Emery paper and polishing powders.
Directions for Making Steel Excavators and Chisels
1. Annealing.—Select the blank of proper size and with
the blowpipe or Bunsen burner heat the point and shank to
full cherry red and allow to cool slowly. This anneals it and
makes it soft and pliable.
2. Place the instrument to be duplicated, or a picture of
it, together with a memorandum of its formula, before you.
3. With the millimeter gauge see if that portion to be made
into the blade will need any change in form or dimensions; if
so, procure the needed change with hammer and anvil or the
file.
If necessary, file the shank down to the proper measure-
4.
ment and taper.
5. Angling.—Bend the shank by means of the pliers till
the proper angles, as mon-angle, bin-angle, triple-angle,
contra-angle, etc., are procured, as indicated by its formula,
verifying them with the instrument gauge and by comparing
with the model to be duplicated.
6. Beveling.—File the cutting edge of the blade to the
proper bevel, verifying all dimensions with the millimeter gauge.
7. Preliminary Polish.—Remove all file marks with fine
emery paper, then take to the lathe and give a high polish,
first using pumice on a felt cone or wheel and later whiting
and water.
