4.3: Cutting and Shaping
- Page ID
- 67235
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4.3 Cutting and Shaping
Once the design is laid out, the rectangular blank can begin to become the finished cutting board.
Do not expect one machine to produce the final shape.
The process usually moves from rough cutting to controlled shaping to final refinement.
Learning Outcomes
After completing this section, you should be able to:
- Choose an appropriate tool for a straight or curved cut.
- Cut an interior opening safely.
- Leave material for final shaping.
- Refine curves using hand tools and sanding equipment.
- Evaluate the shape by both sight and touch.
Cut Close, Not Perfect
When rough-cutting the outside shape, do not try to cut directly on the finished line.
Leave a small amount of material outside the layout line.
That extra material allows you to refine the curve using:
- files;
- rasps;
- spokeshaves;
- stationary sanders; or
- hand sanding.
A rough-cutting machine creates the basic form.
The final shape comes from refinement.
Cutting the Outside Shape
Depending on the design, the outside profile may involve:
- band saw cuts;
- jig saw cuts; or
- another instructor-approved method.
Plan the cutting sequence before beginning.
For tight curves, you may need to make relief cuts so waste can fall away without forcing the blade through an excessively tight turn.
Do not twist or force a blade to follow a curve it cannot safely cut.
Cutting the Interior Handle Opening
The handle opening requires an interior cut, meaning the waste is surrounded by material.
One common method is:
- Lay out the opening clearly.
- Drill an entry hole inside the waste area.
- Insert the jig saw blade through the opening.
- Cut around the interior shape while staying slightly inside the waste side of the layout line.
- Refine the opening with files, rasps, or abrasives.
Depending on the design, the drill press may also be used to establish rounded ends or portions of the opening.
Your instructor will demonstrate the appropriate method for your design.
Protect the Layout Line
The pencil line represents the shape you want to keep.
Whenever possible, leave the line visible during rough cutting.
It is much easier to remove a little more material during shaping than to repair a cut that went too far.
Files and Rasps
Files and rasps are useful for refining areas that are difficult to reach with machines.
Rasps remove material relatively quickly and are useful for developing a shape.
Files usually cut more finely and can be used to refine surfaces after the rough shape has been established.
Use the tool that matches the amount of material you need to remove.
Spokeshaves
A spokeshave can be useful for shaping long outside curves and edges.
Like other cutting tools, it works best when used with favorable grain direction.
If the tool begins tearing the grain rather than cutting it cleanly, change direction or adjust your approach.
Shape by Touch
Do not evaluate the cutting board only with your eyes.
Run your hand along the perimeter.
Feel for:
- flat spots in curves;
- abrupt transitions;
- bumps;
- sharp corners;
- asymmetry that looks accidental; and
- areas that are uncomfortable to grip.
Your hand will often detect problems that are difficult to see.
Work From Coarse to Fine
A useful general sequence is:
Saw → Rasp → File or Spokeshave → Coarse Abrasive → Fine Abrasive
Not every area will require every step.
The goal is to use the most efficient tool for the amount of material that still needs to be removed.
Do not spend twenty minutes sanding away material that could have been removed accurately in one minute with a rasp.
Know When to Stop Shaping
Once the design is resolved, stop changing the form.
Continuing to reshape a nearly finished board can gradually make the project smaller, thinner, or less intentional.
At some point, shaping ends and surface preparation begins.
Check Yourself
- Why should you leave material outside the layout line when rough cutting?
- What is an interior cut?
- Why might you drill a hole before using the jig saw on the handle?
- What is the general difference between a rasp and a file?
- Why should you evaluate the shape with your hands as well as your eyes?