Position the reamer at the top of the hole.
Turn the reamer very slowly in the cutting
direction (clockwise) until the reamer is in the center of
When reaming steel, use cutting oil or
machine oil to lubricate the tool.
When reaming soft iron, do not lubricate
Do not turn the reamer too fast or too
slowly, because this will cause the reamer
to chatter, producing an unevenly reamed
Turn the wrench in the cutting direction
with steady, firm pressure until the reamer
has been turned in the hole.
Turn the reamer in the cutting direction
(direction of the cutting edges) only.
Do not turn reamer backwards at any
time. To do so will result in rapid wear
and dulling of the cutting edges.
Remove the reamer from the hole by
continuing to turn the reamer in the cutting direction and
raising the reamer at the same time.
Repair. Reamers or blades are usually
scrapped when the cutting edges become dull and
Care. Observe the following practices for the
care and upkeep of reamers:
Keep reamers absolutely clean in order to
do accurate work.
If proper pressure is applied during use
and the reamer chatters, replace it to ensure accurate
For short-term storage, wrap the reamer
in an oily cloth and store it in a box.
For long-term storage, clean reamer
thoroughly and coat with rust-preventive compound.
Wrap each reamer separately in oiled cloth and store in
a dry, safe place.
4-17. Hacksaws. Hacksaws are used to cut metal that
is too heavy for snips or boltcutters.
Description. The two parts of the hacksaw are
the frame and the blade
Frame. The frame may be solid or
adjustable, as shown in figure 4-96. Adjustable frames
can be made to hold blades from 8 to 16 inches long,
while those with solid frames take only the length blade
for which they are made. This length is the distance
between the two pins that hold the blade in place. The
blade is installed in the frame with the teeth pointing
forward, and is tightened by turning the handle or a wing
Figure 4-96. Hacksaws
Blades. Hacksaw blades are made of
high-grade tool steel. They are about 1/2-inch wide,
from 8 to 16-inches long, and have a pitch (number of
teeth per inch) of 14,18, 24, or 32.
Temper. Hacksaw blades come in two
types: all-hard, and flexible. The all-hard blades are
hardened throughout, whereas only the teeth of the
flexible blades are hardened.
Set. The set in a saw refers to how
frequently the alternating teeth are set in opposite
directions from the sides of the blade. The three
different kinds of set are alternate set, raker set, and
wave set, as shown in figure 4-97.
Selection. Select a hacksaw blade based on the
thickness and hardness of the stock to be cut.