Smithy MI-409MZ, Руководство оператора

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π = 3.14. You can use an rpm chart for selected diameters of cutting tools at
different cutting speeds.
Change Speeds by selecting the belt location and turning the speed dial
Feeds
Set the direction of feed before you begin milling. Up milling, or conventional
milling, is when the direction of feed is opposite to the direction of cutter
rotation. Down milling, or climb milling, is when the direction of feed is the
same as the direction of cutter rotation.
Up Milling
In up milling, forces on the work piece tend to pull it out of the vise or fixture
holding it, so fasten it securely. These forces also push the work piece away
from the cutter, which eliminates backlash. Up milling is advised for milling
cast iron, softer steels, and other ductile materials. In general, it's how you
should perform milling operations.
Down Milling
Down milling usually produces good surface finishes because chips do not
sweep back into the cut. Setups are more rigid, an advantage when cutting
thin work pieces held in a vise or work pieces held in a magnetic chuck.
Down milling also produces straighter cuts. We recommend down milling
when using carbide cutters because there is less wear on the cutting tool. In
general, however, avoid it because of the backlash problems associated with
it.
Feed Rates
Your feed rates should be as high as your machine, cutting tool, work holding
method, and work piece can tolerate while giving a good finish. Feed rate is
usually given in inches per minute (ipm). You determine feed rate by the
speed of the cutter in rpm and the number of teeth in the cutter.
There are many factors to consider in selecting the feed per tooth, and there
is no easy formula to follow. Here are several principles to guide you:
• Use the highest feed rate conditions allow
• Avoid using a feed rate below 0.001” per tooth
• Harder materials required lower feed rates than softer materials
• Feed wider, deeper cuts more slowly than narrow, shallow cuts
• Slower feed rate gives a better surface finish
• Never stop the feed before finishing the cut
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