Miscellaneous Hand Tools
1. Steel square
2. Straight edge
5. Trammel points
6. Soldering iron
Some of the commonly used hand tools are described as under
1. Folding rule.
It is used in measuring and laying out on sheets larger work with accuracy of 0.5 mm.
2. Steel rule.
It is useful in measuring and laying out small work on sheets. It can also measure up to accuracy of 0.5 mm.
3. Tinrnan’s mandrel.
The body of tinman’s mandrel consists of a flat part and circular parts and serves as a base for carrying out several operations on sheets. The flat part carries a tapered square hole for accommodating the shanks of other stacks. The circular part is required for seaming of pipes and riveting.
Fig. shows a typical trammel and its operations. It is long rod called a beam on which are mounted two sliding heads used to hold scribing points for scribing work on sheets. The points are adjustable in nature and can be replaced by pencils, caliper legs or ballpoints. It is a layout generally required to measure between two points or to scribe large circles or arc too long for divider.
5. Semi-circular protector.
Fig. shows the semicircular protractor whose head is circular and back is flat. It is generally used to for setting bevels, transferring angles and other classes of work on metal sheets.
Flat nose and round nose type pliers are commonly used for holding the sheet work and forming different shapes respectively.
Fig. shows the different kinds of scribers, which are made of hardened steel of 3-5 mm. diameter and 20 cm. long. Its one end is pointed as sharp as possible for making scribing lines on metal sheets.
Fig. shows a typical groover and its operation, which consists of two folded edges called locks. The two edges are hooked together and locked with a grooving tool called hand groover. These tools come with grooves of various width and vary in size. The groover is used for offsetting an outside grooved seam. Initially, the folding edges to 180° are made first. Then the folded edges are hooked together. Finally grooving tool is then used to make strong joint of metal sheets as shown in figure.
9. Hand seamer.
Fig. shows a hand seamer, which is used for bending narrow portions, which are difficult to fold, by other means. It has two adjustable screws, which can be regulated for width of bend. The metal sheet is placed between the jaws and the jaws are clamped together by squeezing the handles to grip the sheet for further bending.
Other hand tools or instruments used in sheet metal shop include rivet sets, soldering iron, scrapers clamps, screw drivers, spanners and wrenches, chisels, different types of calipers and dividers, vernier caliper, micrometers, standard wire and thickness gauges, files for softer metals, conventional types of metal files including needle files and round files.
Source A Textbook of Basic Manufacturing Processes and Workshop Technology by Rajender Singh.