Chapter 12, Lathe facing and knurling – Smithy Midas 1220 LTD User Manual

Page 61

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Chapter 12

Lathe Facing and Knurling

Before removing your work from the centers, face or square up the ends. On accurate

work, especially where shoulders, bevels, and the like must be an accurate distance from

the ends, do the facing before turning the shank. This also cleans the ends and machines

the workpiece to accurate length.

When diameters are large, it's best to face with a special side tool that has a long, thin

blade with a wide cutting edge. If you don't have one, use a right or left-hand facing

cutter. Feed the tool from the center outward to avoid marring the lathe center (Figure

12.1).

Figure 12.1 With a facing cutter, feed the tool from the center outward.

Facing Across the Chuck

When facing a stub-end workpiece held in the headstock chuck, the same rules apply.

Chuck the stock, letting it protrude about an inch. Place a right-hand side tool (or a

straight turning tool with a facing cutter) in the toolpost. Carefully adjust the cutting edge

so it is exactly on center, then tighten it into the toolpost. If you don't do this, a small tit

or projection will remain in the center of the stock and perhaps cause the center drill to

run off center.

Start your lathe on the slowest speed. Bring the tool into cutting position against the

center of the workpiece. Do not start with a heavy feed because the sfm increases

rapidly as the cutter moves through increasing peripheries. One or two light cuts is

usually enough to true up an end roughened by the hacksaw. After facing one end,

reverse the workpiece and face the opposite end.

If you must finish the ends of the shaft, use a half-center (Figure 12.2). This lets you

extend the tool across the entire face of the work.

To use the powerfeed for facing, place the speed selector into the desired position before

the lathe is turned on. Once the cutter has been positioned as per the above paragraph,

12-1

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