Band Sawing
Only high speed saws with a blade speed of 3,000 to 6,000 feet per minute (915
to 1830 m/min) should be used. They should be of tempered steel with a 15
degree minimum top rake and 4 to 8 teeth per inch (160 to 320 per meter). Proper
support for the plate being cut is mandatory and will help maintain flatness
tolerances during sawing.
Drilling
The recommended drills for cast plate should have more twists per inch than
ordinary drills. The flutes of these drills should be highly polished. Cutting
compound should be used.
Turning
Lathes capable of turning the stock at
5,000 to 9,000 surface feet per minute
(1525 to 2745 m/min) should be used. Use
carbide tipped tools with a 40 degree top
rake and 18 degree side rake angle. Feed
should not exceed .020 inches (0.5mm)
per revolution.
Tapping
Hand or machine taps will produce
smooth and accurate threads in MIC6
®
cast plate. For a full thread, the tap drill
should be of slightly less diameter than
that used for steel. Rounded or trapezoidal
threads are recommended - thread length
should be 20% longer than for steel.
Inserts will prolong the thread life.
Surface Exposure
As machined MIC6
®
parts have successfully performed over decades of service
without evidence of corrosion or abnormal surface oxidation. Exterior and other
environments that are high in moisture tend to induce the development of surface
staining and pitting. Marine exposures should be avoided.
Thermal Cycles
MIC6
®
can be repetitively cycled through a thermal exposure without affecting or
altering the physical properties of the plate. Thermal treatments during each cycle
can range from 250 to 600°F (120 to 315°C). Full support under the plate during
the thermal cycle is recommended - the thinner the plate, the more important this
consideration becomes.
16
BLACKBURNS METALS LIMITED
MIC6
®
