Planishing (from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

''planus'', "flat") is a

metalworking Metalworking is the process of shaping and reshaping metals in order to create useful objects, parts, assemblies, and large scale structures. As a term, it covers a wide and diverse range of processes, skills, and tools for producing objects on e ...

technique that involves finishing the surface of

sheet metal Sheet metal is metal formed into thin, flat pieces, usually by an industrial process. Thicknesses can vary significantly; extremely thin sheets are considered foil (metal), foil or Metal leaf, leaf, and pieces thicker than 6 mm (0.25 ...

by finely shaping and smoothing it.

Process

A metal surface is finished by hammering it with a planishing panel hammer or slapper file against a shaped surface called a ''planishing stake'' that is held in a vise or a mounting hole in a blacksmith's beak anvil, or against hand-held, shaped, metal tools that are known as ''dollies'' or ''anvils''. The shape of the stake or dolly has to match the desired work piece contour, and so they come in a variety of complex shapes. Alternatively, planishing may be done by the use of an

English wheel The English wheel, in Britain also known as a wheeling machine, is a metalworking tool that enables a craftsperson to form compound (double curvature) curves from flat sheets of metal such as aluminium or steel.Parker, Dana T. ''Building Victory ...

. After approximately forming a metal object, by stretching with techniques such as

sinking Shipwrecking is any event causing a ship to wreck, such as a collision causing the ship to sink; the stranding of a ship on rocks, land or shoal; poor maintenance, resulting in a lack of seaworthiness; or the destruction of a ship either intent ...

and

raising Raising may refer to: *Raising (syntax), a syntactic construction *Raising (sound change), a sound change *Raising (metalworking), a metalworking technique *Barn raising, a community event to erect the wooden framework for a building *Fundraising, ...

, and then shaping and smoothing an object, metal workers use planishing for surface finishing. Planishing is a hand-driven process used in auto body repair and

craft work such as medieval armour production.

Tools

Common tools used for planishing include panel beating hammers, slappers, and neck hammers. Heavy rawhide or hardwood hammers are often used. It is more difficult to make mistakes with heavy rawhide or wood mallets, but they are less effective for large imperfections. A worker, using repeated, relatively soft glancing blows, smooths the metal toward the curvature of the stake. If the metal begins to look dimpled, the worker is using too much force in individual hammer blows.

Features

Since planishing hammers are generally in contact with the outside surface of the piece, they are flat, have rounded edges and are polished to avoid marring the work.

Pneumatic Pneumatics (from Greek 'wind, breath') is the use of gas or pressurized air in mechanical systems. Pneumatic systems used in Industrial sector, industry are commonly powered by compressed air or compressed inert gases. A centrally located a ...

(air powered) planishing hammers strike hundreds of blows per minute.Air Planishing Hammers
Grainger, lists hammers available with 1800 to 5400 Blows per Minute, accessed 10 June 2020. Care must be taken not to allow sheet metal to harden and become brittle during planishing. If it does, it must be annealed.

References

Notes Bibliography * * {{cite journal , doi=10.1017/S0003598X00073580, title=A Harappan 'snarling iron' from Chanhu daro , year=1988 , last1=Yule , first1=Paul , journal=Antiquity , volume=62 , issue=234 , pages=116–118 , s2cid=164079367 , url=http://crossasia-repository.ub.uni-heidelberg.de/145/1/yule_snarling_iron.pdf Metal forming