HOW TO SELECT AND USE POWER HACK SAW BLADES
Power hack saws automatically take a Full
Stroke each time, automatically Lift the blade on reverse
for a better bite, without clogging, by selecting the
stroke and apply steady cutting pressure throughout the
coarsest tooth for the work. (The feed-pressure-per
length of the stroke.
tooth must be kept below the point of fracturing the
teeth.) Large Sections and soft materials require coarse
The proper tensioning of the power hack saw
teeth. Thin sections and hard-to-machine materials
blade is most important. Insufficiently tensioned blades
require fine teeth.
wear rapidly, cut inaccurately and deliver a blank with a
A blade tensioned too tightly breaks
USE HEAVY FEED PRESSURE
prematurely or pulls out at the pin hole.
Normally you should set the feed pressure as heavy
as possible without breaking the teeth or making the
blade cut crooked. Excessive pressure and stroke
speed increase the cutting rate at the expense of blade
wear. (When in doubt, keep pressure at maximum but
reduce the stroke speed).
The heaviest practical pressure . . . and the
fastest reasonable stroke speed produce the most
If chips are burned you are feeding too heavy. If
chips are fine and powdery you are feeding too light. A
A feed-rate that is too light results in rubbing
free cut with
curled chips indicate ideal feeding
Instead of cutting; (tooth points overheat, soften and
pressure, fastest cutting time and longest blade life.
For most cutting jobs, the all-hard blade is first
For optimum feed rate: Use heavy feed for hard,
choice for straight, accurate cutting.
very dense material-light feed for thin soft material. For
tungsten blade is unexcelled for retaining its sharp teeth.
maximum production, you can increase feed by using
It handles work hardening materials, abrasive materials,
coarse blades on soft materials. But remember to use
moderate feed when straight, accurate cutting is
machinability bronzes. Molybdenum blades are good for
fast, accurate cutting, but especially on low or medium
alloy steels, iron and most non-ferrous metals.
USE PLENTY OF COOLANT
Start the coolant flow before the first cutting
stroke. Coolant is needed on all materials (except cost
iron, copper and some brasses) to reduce friction, blade
wear, and chip clogging. Keep coolant flowing until job is
finished and the blade Is stopped.
More pressure can be applied