Safety Measures & Brief Insight
- Always face the cutting edge of the tools away from yourself
- Keep your fingers clear of the tool’s trajectory
- Keep your eyes protected
- Avoid using blunt tools
- Keep your workspace tidy
The try-square is used to check for right angles on a workpiece.
The caliper allows measurements of up to 0.1 mm for depths, internal and external dimensions.
Eg. Inner jaws – internal diameter of pipes
Outer jaws – thickness of blocks
Depth gauge – rabbets
The 3 saws that we use and provide have angled teeth. If it is angled towards the handle, it would require a pull stroke. However, if the teeth are angled away from the handle, it would naturally require a push stroke.
A detachable blade would then allow the tool to be realigned to a push or a pull stroke.
Coping – It has a thin blade that cuts curves and is detachable.
Hack – It is best for straight cuts and is detachable as well.
Back – It has a thick blade that only cuts straight.
There are many ways a chisel can be used to carve wood. The angle of the cut is determined by the angle the chisel is held at. Holding the chisel with the bevel up or down also affects the cut made by the chisel.
1.11 Checking the accuracy of a Try-Square
Place the try-square flush against an object’s straight edge (e.g. a piece of wood) and draw a perpendicular line. Flip the try-square horizontally and check if the same edge aligns with the drawn line. The try-square is accurate if both edges of the ruler are squared to the drawn line.
1.12 Measuring & Marking
If your try-square is properly square (see 1.11), you can use it to check for right angles such as on a workpiece or a right-angled joint.
The try-square can also be used as a ruler to make measurements and markings.
1.2 Measuring & Scribing with CalipersTechniques
1.21 How to measure
The first measurement is determined by where the 0-point on the vernier scale crosses the main. In the example below/on the right, it is 45mm.
Secondly, read the measurement on the vernier scale that aligns with the main. As shown, it is 0.5mm.
Therefore bringing it to the final measurement of 45 mm + 0.5 mm = 45.5mm.
1.22 Compensating for Zero error
A zero error is present when the 0-point on both scales do not align when the jaws are fully closed or the depth gauge is flat.
The reading will be based on the vernier scale that aligns with the main, (0.1mm).
If the 0-point is found left to the main scale, there is a negative zero error. Conversely, if the 0-point is found right to the main scale, there is a positive zero error.
Negative zero error – Obtained reading is smaller than correct reading.
Positive zero error – Obtained reading is bigger than correct reading.
Correct reading = Obtained reading – Zero Error
Lock the calipers at the intended measurement and align the outer jaws on the edge of your workpiece. Make sure the caliper is held upright in order for the inner jaw to lightly pierce the surface of the workpiece. With a comfortable grip on the caliper, scribe the wood quickly and steadily. The scribed line produced should be consistent and straight.
1. Mark the desired cut on at least 2 sides of a workpiece if you are making a rough cut (e.g. cross-cut to divide a plank in two). Mark all 4 sides of the workpiece for more precision (such as in the case of a joint) as this will also guide the chisel-work afterwards. You can use a square to draw these lines.
2. When using a push saw (refer to the above/left image), position your workpiece in front of the holdfast so that it will prevent the workpiece from moving with the forward motion of the saw. Conversely, position the workpiece behind the holdfast when using a pull saw.
3. Align the saw outside of your drawn line.
4. To steady the saw, anchor your knuckle against the side of the blade. This will keep the blade aligned with your drawn line and at a constant angle.
5. Establish a clear line first with a few light strokes before severing more material with push/pull strokes.
6. Be sure to saw lightly with long strokes, this prevents it from getting jammed.
1.41 Using a Chisel with a Mallet
With a hammer or mallet, you can drive a chisel into wood. This can be used to set down a knife line, or to chop out large amounts of waste material.
Knife lines are shallow cuts that sever wood fibers and act as a stop cut to prevent tear-outs. They are usually used to outline a joint (e.g. a mortise or the shoulders of a tenon).
How to make a knife line: Align the cutting edge of the chisel on your marking line, with the bevel facing towards the waste. Holding the chisel perpendicular, tap lightly with a mallet or hammer.
Chopping is a method to quickly remove large amounts of waste material using the chisel.
How to chop: Hold the chisel upright with the bevel side of the chisel facing towards the waste, place the cutting edge of the chisel on the inside of the knife line before chopping to prevent cutting over the knife line. By applying more force with a mallet or hammer, you can sever more fibers thus removing more material. The angle of your chisel can vary depending on the amount of material you are trying to chop out. As this is an aggressive cut, it can cause tear-outs or cracking in the material.
A “v” cut made with the bevel down can be made identical with the bevel up. But this is unwieldy as the chisel will be held at a much lower angle. This may also cause the wood to slide since the chisel is being hammered forward. For a more effective cut, face the bevel down.
Paring cut is often used after chopping to clean up and flatten the surfaces of a joint. It removes less material with each cut which allows for a more precise and cleaner cut.
How to pare: Hold the chisel flat on the surface with the bevel side up. With only the force of your hand, move the chisel diagonal to the wood grain to slice material using the chisel’s cutting edge.
Scraping removes a very minimum amount of material and is mainly used to clean up small tear outs on the surface of a joint, or to smoothen wood to a finish.
How to scrape: Hold the chisel with the bevel up at a high angle, pull the cutting edge towards yourself such that it produces a scraping effect upon a surface.
2. Basics of Tool Maintenance
Preserving your hand tools can be an on-going task, but it can also maximise your productivity!
3. Basics of Joinery
Learn how to create a Through Mortise & Tenon, Through Dovetail, Sliding Dovetail or Half-blind Dovetail.
7 Mandai Link #10-22 S728653