| Questions | 5 |
| Topics | Calipers, Hacksaw, Punches, Rulers, Soldering |
Calipers are similar to micrometers in shape but instead of measuring distances, calipers are used to transfer distances between objects. An outside caliper is used to transfer outside dimensions while an inside caliper is used to transfer inside distances. A vernier caliper is an extremely precise caliper (down to \({1 \over 1000}\) inch) that allows measuring / transferring either inside or outside dimensions.
A hacksaw has replaceable blades and is used to cut metal. The blade type is chosen based on the material that is to be cut. Blades with larger numbers of teeth per inch are more appropriate for cutting thinner materials.
A punch is narrow and is used to drive objects like nails (pin punch) or for making guide marks for drilling (center punch) or patterns in wood or metal.
Rulers are used to both measure distance and to draw straight lines. Tape measures are flexible rulers made from cloth or metal and are useful for measuring longer distances and in tighter spaces. Both rulers and tape measures provide similar accuracy, commonly down to \({1 \over 16}\) or \({1 \over 32}\) inch. A steel framing square is made up of a shorter ruler (tongue) and a longer ruler (blade) that meet at a 90° (right) angle. A framing square is often used by carpenters when framing stairs and roofs.
Soldering is a low-temperature process by which two or more items (typically metal) are joined together by melting a filler metal (solder) into the joint. An electrically powered soldering iron or soldering gun is used to melt the solder which is an alloy of lead and tin that has a melting point below the melting point of the items being joined. A chemical cleaning agent called flux is also used to clean the surfaces before soldering.