Instruction example 4.2. Stands and supports
To practise straight saw-off cuts in several steps on U-sections
and tubes. U-sections may be used as basic bodies for drill stands, tubes as
supports (table legs), training example 4.6.
Material
U-sections of steel (340 MPa)
Web width: 80 mm
Flange
height: 45 mm
Steel tube (340 MPa)
25 mm diameter
Figure
Hand tools
Steel scriber, hand hacksaw (saw blade of normal tooth pitch),
smooth-cut file 200 mm (flat), mark-out punch, engineers’ hammer.
Measuring and testing tools
Steel measuring tool, try square.
Accessories
Vice, surface plate, spacer (wooden block) for clamping of
U-section, horizontal Vee-shaped attachment suitable for tube diameter, cutting
oil.
Required previous knowledge
Reading of drawings, measuring and testing, scribing and
prick-punching.
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Sequence of operations |
Comments |
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1. Arrange the working place, prepare the working materials.
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- Check for completeness. |
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2. Scribe U-section for 120 mm length using try square and steel
measuring tool, prick-punch scribed line. |
- File datum edge, if end face is not flat. |
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3. Clamp workpiece in vice at web using suitable attachment and
file guiding kerf at upper face (flange). |
- Part (1) |
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4. Saw until upper face (flange) is cut off, then re-clamp and
saw web, then re-clamp and saw off other flange, remove burrs. |
- Use total length of saw blade. |
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5. Clamp steel tube in vice in horizontal position using
Vee-shaped attachment. Scribe length as specified and file guiding kerf. |
- Length to be specified by the instructor. |
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6. Saw until saw blade cuts off inner wall, then slightly turn
tube and continue sawing. |
- Part (2) |
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7. Saw off the tube constantly turning it. |
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8. Final inspection. |
- Straightness of cut. |
Prepare several U-sections for different drill stands (training
examples 2.3 and 7.4).
