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34
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2016
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Read Books Ltd.
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34
pages
English
Ebook
2016
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Obtenez un accès à la bibliothèque pour le consulter en ligne En savoir plus
Publié par
Date de parution
06 septembre 2016
Nombre de lectures
0
EAN13
9781473353237
Langue
English
Publié par
Date de parution
06 septembre 2016
Nombre de lectures
0
EAN13
9781473353237
Langue
English
WROUGHT IRONWORK
A Manual of Instruction for Rural Craftsmen
Copyright 2013 Read Books Ltd.
This book is copyright and may not be reproduced or copied in any way without the express permission of the publisher in writing
British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library
Metal Work
Metalworking is the process of working with metals to create individual parts, assemblies, or large-scale structures. The term covers a wide range of work from large ships and bridges to precise engine parts and delicate jewellery. It therefore includes a correspondingly wide range of skills, processes, and tools. The oldest archaeological evidence of copper mining and working was the discovery of a copper pendant in northern Iraq from 8,700 BC, and the oldest gold artefacts in the world come from the Bulgarian Varna Necropolis and date from 4450BC. As time progressed, metal objects became more common, and ever more complex. The need to further acquire and work metals grew in importance. Fates and economies of entire civilizations were greatly affected by the availability of metals and metalsmiths. The metalworker depends on the extraction of precious metals to make jewellery, buildings, electronics and industrial applications, such as shipping containers, rail, and air transport. Without metals, goods and services would cease to move around the globe with the speed and scale we know today.
One of the more common types of metal worker, is an iron worker - who erect (or even dismantle) the structural steel framework of pre-engineered metal buildings. This can even stretch to gigantic stadiums and arenas, hospitals, towers, wind turbines and bridges. Historically ironworkers mainly worked with wrought iron, but today they utilize many different materials including ferrous and non-ferrous metals, plastics, glass, concrete and composites. Ironworkers also unload, place and tie reinforcing steel bars (rebar) as well as install post-tensioning systems, both of which give strength to the concrete used in piers, footings, slabs, buildings and bridges. Such labourers are also likely to finish buildings by erecting curtain wall and window wall systems, precast concrete and stone, stairs and handrails, metal doors, sheeting and elevator fronts - performing any maintenance necessary.
During the early twentieth century, steel buildings really gained in popularity. Their use became more widespread during the Second World War and significantly expanded after the war when steel became more available. This construction method has been widely accepted, in part due to cost efficiency, yet also because of the vast range of application - expanded with improved materials and computer-aided design. The main advantages of steel over wood, are that steel is a green product, structurally sound and manufactured to strict specifications and tolerances, and 100% recyclable. Steel also does not warp, buckle, twist or bend, and is therefore easy to modify and maintain, as well as offering design flexibility. Whilst these advantages are substantial, from aesthetic as well as financial points of view, there are some down-sides to steel construction. It conducts heat 310 times more efficiently than wood, and faulty aspects of the design process can lead to the corrosion of the iron and steel components - a costly problem.
Sheet metal, often used to cover buildings in such processes, is metal formed by an industrial process into thin, flat pieces. It is one of the fundamental forms used in metalworking and it can be cut and bent into a variety of shapes. Countless everyday objects are constructed with sheet metal, including bikes, lampshades, kitchen utensils, car and aeroplane bodies and all manner of industrial / architectural items. The thickness of sheet metal is commonly specified by a traditional, non-linear measure known as its gauge; the larger the gauge number, the thinner the metal. Commonly used steel sheet metal ranges from 30 gauge to about 8 gauge. There are many different metals that can be made into sheet metal, such as aluminium, brass, copper, steel, tin, nickel and titanium, with silver, gold and platinum retaining their importance for decorative uses. Historically, an important use of sheet metal was in plate armour worn by cavalry, and sheet metal continues to have many ornamental uses, including in horse tack. Sheet metal workers are also known as tin bashers (or tin knockers ), a name derived from the hammering of panel seams when installing tin roofs.
There are many different forming processes for this type of metal, including bending (a manufacturing process that produces a V-shape, U-shape, or channel shape along a straight axis in ductile materials), decambering (a process of removing camber, or horizontal bend, from strip shaped materials), spinning (where a disc or tube of metal is rotated at high speed and formed into an axially symmetric part) and hydroforming. This latter technique is one of the most commonly used industrial methods; a cost-effective method of shaping metals into lightweight, structurally stiff and strong pieces. One of the largest applications of hydroforming is in the automotive industry, which makes use of the complex shapes possible, to produce stronger, lighter, and more rigid body-work, especially with regards to the high-end sports car industry.
One of the most important, and widely incorporating roles in metalwork, comes with the welding of all this steel, iron and sheet metal together. Welders have a range of options to accomplish such welds, including forge welding (where the metals are heated to an intense yellow or white colour) or more modern methods such as arc welding (which uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point). Any foreign material in the weld, such as the oxides or scale that typically form in the fire, can weaken it and potentially cause it to fail. Thus the mating surfaces to be joined must be kept clean. To this end a welder will make sure the fire is a reducing fire: a fire where at the heart there is a great deal of heat and very little oxygen. The expert will also carefully shape the mating faces so that as they are brought together foreign material is squeezed out as the metal is joined. Without the proper precautions, welding and metalwork more generally can be a dangerous and unhealthy practice, and therefore only the most skilled practitioners are usually employed.
As is evident from this incredibly brief introduction, metalwork, and metalworkers more broadly, have been, and still are - integral to society as we know it. Most of our modern buildings are constructed using metal. The boats, aeroplanes, ships, trains and bikes that we travel on are constructed via metalwork, and mining, metal forming and welding have provided jobs for thousands of workers. It is a tough, often dangerous, but incredibly important field. We hope the reader enjoys this book.
WROUGHT IRON GATE
Probably made by Warren about 1720. It stands at the entrance to Clandon Park, seat of the Earl of Onslow.
Contents
PREFACE
INTRODUCTION
Tools
Transferring a drawing on to a metal plate
PART I
CHAPTER 1 SCROLLS
LESSON
1 Ribbon-end scroll
2 Fishtail-end scroll
2 Solid snub-end scroll
3 Fishtail snub-end scroll
4 Halfpenny snub-end scroll
5 Bolt-end scroll
6 Blow-over leaf scroll
7 Making a scroll tool
8 C scrolls
9 S scrolls
10 Collars
CHAPTER 2 TWISTS, WAVY BARS AND WATER LEAVES
LESSON
11 Twists
12 Wavy bars
13 Water leaves
CHAPTER 3
LESSON
14 Square blockings for gate rails
PART II
CHAPTER 4 MAKING AN ORNAMENTAL GATE
LESSON
15 Height and width rod
16 The bottom heel bar
17 Tenon for the centre rail
18 The back stile
19 The latch slot
20 Vertical bars
21 Balls for the centre panel
22 The centre panel
23 The side panel
24 Dog bars
25 Hanging for the gate
26 The latch pivot
27 The latch
CHAPTER 5 FITTING AND ASSEMBLING THE GATE
28 The journal
29 Slotting the middle rail
30 Putting the frame together
31 Fitting the hanging, riveting the gate
PART III
CHAPTER 6 PAINTING WROUGHT IRONWORK
PREFACE
In recent years, wrought ironwork has regained some of its previous popularity and it seems likely that the severity of our modern buildings may be relieved by this traditional form of decoration.
Orders for wrought ironwork are welcomed by many rural blacksmiths, not only for the income they bring, but as a pleasant change from the daily routine of an agricultural smithy. Some smiths are, however, out of practice and lack confidence in their skill. So this book has been prepared by the Rural Industries Bureau, which provides a national advisory service for rural craftsmen, to help them to refresh their technical knowledge and to provide apprentices with a basic introduction to this subject. It will also supplement the practical instruction which the Bureau gives to rural craftsmen in their own workshops.
Detailed advice on design, which is a most important aspect of the craft is not given here; but a high degree of technical skill is of no avail if a sense of design is lacking. This can be developed by taking every opportunity to see fine examples of traditional and contemporary wrought ironwork, and by supplementing this with a careful study of the books which are listed on page 94 . The Bureau publishes a Design Catalogue of Wrought Ironwork which is sold to the public, although the library of the working drawings is only available to rural craftsmen.
The system of describing techniques by sequences of still photographs, briefly captioned, proved very successful in the Blacksmith s Craft and has been used again in this book. Where methods vary, the one most suitable for the beginner has been described.
The collection and recording of the knowledge and skil