Chapter 18, Workholding – Smithy Midas 1220 LTD User Manual

Page 92

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Chapter 18

Workholding

The most common ways to hold a workpiece during milling are to secure it directly to the

table via clamps or hold it in a vise (Figure 18.1). If you're making many similar work-

pieces, you may make a special fixture to hold them. Whatever method you use, hold the

workpiece securely so it won't shift during machining and support it adequately to avoid

swing.

Figure 18.1 Workholding set up (Missing)

Mounting to the Table

If you need to align the workpiece to the table, place it against stops that exactly fit the

table's T-slots. Another way is to measure in from the edge of the table to the workpiece.

Be sure the table and workpiece are clean and free of burrs. Another method is to use

the face of the spindle plate, chuck or taistock as a quick reference surface.

Using a Vise

Vise sizes are designated by the width of the vise jaw in inches or millimeters. Plain and

swivel vises range from 3 to 10" (76 to 254 mm). Tilting and universal vises range from

3-4" to 5" (76-102 mm to 127 mm).

The bases of many vises are fitted with keys-small steel blocks that fit into the milling

table T-slot for quick alignment of the vise. Before mounting a vise, make sure the

bottom is clean and smooth. If there are any nicks or burrs, remove them with a honing

stone. Set up the workpiece securely and correctly, and fasten the vise tightly to the table.

Plain vises have a flanged base with slots that lets them bolt to the table with the jaw

faces either parallel to, or at 90° to, the longitudinal table travel. Swivel vises have a

swivel base that bolts to the table. They're marked with degree graduations that let you

position their jaws at any angle without moving the base. Universal vises tilt up or

sideways, or swivel. They hold workpieces machined at a double or compound angle.

Tilting vises are like universal vises except they do not tilt sideways.

NO IMAGE. NO AVAILABLE ACCESSORY FOR SET-UP.

18-1

For Assistance: Call Toll Free 1-800-476-4849

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