Finishing of flat wide and narrow faces involves the following operations:
Clamping of the workpiece in a carpenters bench or work bench with the face to be finished on top
- To avoid pressing marks on the workpiece, clean packing faces of wood or other solid materials are to be used.- Long workpieces are to be supported at the free end by a vertically adjustable rest.
- The working direction and grain direction of the workpiece are to be taken into account.
Planing with the double plane and fine-chip setting
The planing strokes should be long and overlap a little.
Working with the scraper
The scraper is mainly used for finishing of hard wood. With soft wood, the wood grains would press into the face during working and no chip would be removed.
The scraper is to be guided lightly over the face with both hands
- with drawing cut,
- with the ridge edge slightly oblique to the working direction,
- parallel, oblique or square to the wood grain direction, depending on the requirements.
Figure 8 Guiding direction of scraper
Sanding with sanding tools
Sanding includes the steps:
- Selection of the flexible sanding tool.- Selection of the sanding pad.
- Wrapping the flexible sanding tool around the sanding pad and holding it with the hand.
- Sanding movements to be performed with slight, uniform pressure on the face in the following working directions:
· across the wood grain in the case of surfaces to be provided with covering coat of paint,
· parallel to the wood grain in the case of surfaces with straight-line grain direction,
· circular or with the wood grain in the case of surfaces with irregular grain direction.
- Uncovered edges of the workpiece are to be sanded throughout (smoothing off of edges) with slight, uniform pressure.
Figure 9 Holding of the flexible
sanding tool at the sanding pad
Checking the surface for flatness and smoothness.
The surface quality is to be checked by:
- comparison of the face with a straightedge according to the light-gap testing method.
- sighting over the face.
The face is flat if the sighted workpiece edges are congruent.
The face is smooth if no shadow effect caused by irregularities is visible.
- touching the face with the hand.
The face is smooth if no irregularities are sensible.
Why must uncovered workpiece edges be
sanded?
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