While working on sheet metals, a worker has to carry out a number of operations, which require the use of some typical bench equipment or tools; generally called bench stakes. These are used for bending or forming sheet metal articles. Stakes are generally made of wrought iron. Stakes consist of a shank and a head or horn. These shanks are held in vices or tin man’s horses. The head and horn are available in various shapes and sizes. Their working faces are machined or ground to shape. Following are the most commonly used stakes.
Hatchet Stake – It has a sharp straight edge, slanted along one side. It is very useful for making sharp bends, folding the edge of sheet metal, folding boxes and panes by hands, and for firm setting of wired edges.
Half Moon Stake – This stake has a sharp edge in the form of an arc of a circle, slanted along one side. It is used for turning over the edges of cylindrical & conical articles and for wiring edge of curved work.
Funnel Stake – It is used for shaping and grooving conical articles, suchas shaping of body of a funnel and forming a grooved seam along with such articles. This is also used for removing dents of conical articles.
Pipe Stake – These are of two types:
(a) Tapered Pipe Stake
(b) Parallel Pipe Stake
These are used for marking off, straightening, reducing, stretching and removing dents from the pipes.
Creasing Iron – It has two rectangular shaped horns, one of which is plane. The other horn contains a series of grooving slots of various sizes. It is used to reduce the diameter of small tubes, produce a groove or a crease in sheet metal and also in the process of wiring (setting and stretching of wired edge).
Tinsmith’s Horse – Different types of tinsmith’s heads are used in the process of planishing, forming and raising of hollowed articles. These are normally mounted on a Tinsmith’s horse, while working.
Tin Smith’s Head – Tinsmith’s horse has different types of heads, which are, inter changeable and may be used in manufacturing different types of sheet metal works.
Tin Smith’s Anvil – It is a heavy wrought iron block with high carbon steel face, which should always be kept highly polished. The anvil is used for planishing or flattening sheet metal only. It should never be used as a block for chipping.
Beak Stake or Beak Iron – It has two horns, one of which is tapered, the other a rectangular shaped anvil. The thick taper or “beak” is used when working on conical, cylindrical and sharp tapering articles. Rectangular shaped anvil may be used for squaring corners, sealing and light riveting.
Bottoming Stake – It is used for flattening or bringing level of sheet metal articles’ bottoms such as traps pane corners.
Solid or Cast Mandrel or Bench Bar – It is solid wrought iron bar which has nearly half of the portion round or oval shape and the rest trapezium. Both the ends are shaped to 60o and the trapezium side has a square hole for accommodating stakes and tinsmith’s heads. Mandrel is used for forming different shapes on sheet metals, i.e. oval, cylindrical, square, or rectangular works and for removal of dents and wrinkles. Hollow mandrels are also available. Some mandrels have bend at the round portion for bending of tubular jobs .The smaller ones are 3 feet in length and the larger ones are 5 feet in length.
Canister Stake – It has square or round, flat working surface. It is mainly used for working in corners and squaring up seams when working with square or rectangular articles. It is also used for forming or shaping the bottoms of canister (long narrow articles) and for flanging of small round discs.
Some General Points on Stakes – Some general points to be remembered while working with stakes are as given below:
(a) If a stake has been roughened by center punch marks or chisel marks, such marks will be impressed upon the surface of the work piece and spoil its appearance.
(b) A stake should never be used for back up work directly while center punching or cutting with cold chisel.
(c) A mallet should be used whenever possible when shaping sheet metal. A great care is needed while using hammers.
(d) Stakes should be regularly maintained.