Monday, May 31, 2010

Barrel Making: Pattern Welded or Damascus Barrels

In our last post about early barrel making techniques in Europe, one of the techniques we studied was the making of the Canon a Ruban type barrels in France. On reading that article and viewing the picture of that barrel, the reader cannot but note the beautiful striping pattern on the barrel showing the grain of iron. Now we will study another method of manufacturing barrels, that originated not in Europe, but in India!

First we start with something called "Damascus Steel". What is popularly known in Europe as "Damascus Steel" was really a type of steel called wootz steel that originated in Southern India around 300 BC. The crusaders originally encountered swords made of this steel in Damascus, Syria and that's how it got its name. These steels were noted for their sharpness and toughness. One of the characteristics of swords made wootz steel is a banding pattern on the blade. Thus, any sword with the characteristic banding pattern was considered to be extremely high-quality.

While the wootz steel owed its qualities to certain impurities found in the ore from a specific mine in India, another way was found to reproduce the beautiful wavy patterns on a blade.

This technique was called "Pattern Welding" and was known to several cultures indeed. The Japanese used it to manufacture their swords since 1100 AD and the Vikings and Celts were using it around 600 AD, as were the ancient Germans. The idea was to use bars of two or more types of steel (0r iron and steel), one having less carbon content than the other and forge them together into a single bar, by heating, twisting and hammering as needed and then fold the bar onto itself and hammer forge it again and repeat the process of heating, twisting, folding and hammering multiple times, resulting in a bar with layers of steel of different types. Such a bar is called a pattern welded or laminated steel bar. The multiple repeated processes of twisting, folding and hammering causes the resulting steel to be purified of impurities and form a tougher steel. The resulting steel has wavy lines and patterns visible due to the difference in chemical composition between the different bars used. An example of steel produced with this method is shown below. Note the beautiful figurations on the blade, which is characteristic of pattern welded steel:


By 1570, pattern welding was used in the manufacture of gun-barrels in India, according to the Ain-i-Akbari written by Abul Fazl, the court historian of the Mughal emperor Akbar of India. From volume 1, we have the following chapter:

ON MATCHLOCKS
"These are in particular favour with His Majesty, who stands unrivalled in their manufacture, and as a marksman. Matchlocks are now made so strong, that they do not burst, though let off when filled to the top. Formerly they could not fill them to more than a quarter. Besides, they made them with the hammer and the anvil by flattening pieces of iron, and joining the flattened edges of both sides. Some left them, from foresight, on one edge open but numerous accidents were the result, especially in the former kind, His Majesty has invented an excellent method of construction. They flatten iron, and twist it round obliquely in form of a roll, so that the folds get longer at every twist then they join the folds, not edge to edge, but so as to allow them to lie one over the other, and heat them gradually in the fire. They also take cylindrical pieces of iron, and pierce them when hot with an iron pin. Three or four of such pieces make one gun or, in the case of smaller ones, two. Guns are often made of a length of two yards those of a smaller kind are one and a quarter yards long, and go by the name of bamdnak. The gunstocks are differently made. From the practical knowledge of His Majesty, guns are now made in such a manner that they can be fired off, without a match, by a slight movement of the cock."

Around the early 1600s, the technique had spread to the Ottoman Empire and later to Hungary and Spain by the 1650s. The defeat of the Turks in the Siege of Vienna in 1683 yielded thousands of captured pattern welded barrels for examination, and this event accelerated the manufacture of pattern welded barrels in Europe. By 1700, the Belgians were producing pattern welded barrels in Liege, and in the early 1800s, the technique was used in England to produce high quality sporting barrels.

Even though making steel through pattern welding is a vastly different process than producing wootz steel, they both have similar wavy watering patterns in the final product. However, since wootz steel was becoming rarer, due to the fact that the mine in India where the special ore was mined from was running out of ore, it wasn't used to make gun barrels very much. William Greener in his Gunnery in 1858: Being a Treatise on Rifles, Cannon and Sporting Arms writes that on examination of barrels made by wootz steel workers, most were actually were made of commonest iron with a very thin plate of wootz steel around them, indicating that the wootz steel ore was becoming very valuable. In fact, when anyone refers to "damascus barrels", they are almost certainly referring to barrels made by the pattern welding method, not barrels made out of wootz steel.

We will refer to some details about the technique of pattern welding used in India, written by Lord Egerton of Tatton, from his book Indian and Oriental Arms and Armor, published in 1896. This section is reproduced from an article from that book, found on damascus-barrels.com

It is said that the Persians distinguish by ten different names the varieties of watering. One of the most prized and rare is that which takes its name from the grains of yellow sand. There are, however, four main patterns generally recognized:

1. " Kirk narduban," meaning the forty steps or rungs of the ladder, in allusion to the transverse markings of fine grey or black watering. The idea is also expressed in an inscription on one of the blades, that the undulations of the steel resemble a net across running water.

2. " Qara khorasan," nearly black, with fine undulations proceeding like water either from the point to the hilt, or the reverse way.

3. Qara Taban, " brilliant black," with larger watering and more grey in tone.

4. Sham, or simple Damascus, including all other varieties. On the introduction of the use of firearms, the methods long and perhaps exclusively known to the Asiatics, of manufacturing sword-blades of peculiar excellence, was transferred with some modification to that of gun-barrels, and are still in use.

In addition to those, Sir J.I. Burnes mentions " Akbaree," in which the pattern ran like a skein of silk the whole length of the blade, and "Beguraee," where it waved like a watered silk.

In Persia, Kabul, the Punjab, and Hind the same general principles prevail, but the matchlocks of the last are held deservedly in the highest estimation.

In some parts of India the workmen prefer for the material of their barrels the iron of old sugar boilers, but they use in Kashmir the iron of Bajaur (in the country of the Yusufzai) as it comes from the smelting furnace, after receiving a few blows whilst hot, which condense it into a rude kind of pig, the weight of which varies from five to eight seers (10 to 16 Ibs.), and which sells
as high as 4d. a pound. The first process consists in cutting the pig when heated into narrow strips with a cold chisel, and in this operation the iron loses one-fourth of its gross weight. Each of these strips separately is brought to welding heat, and worked smartly under the hammers of two men on a block of limestone as an anvil. When the slag is expelled, each strip is drawn out by the hammer into a strap about 2 feet long and 11/5 inch broad, and 1/5th inch thick. One of these straps has its ends so brought together as to enable it to include about 20 other short straps cut up for the purpose, some being placed on their edge, and others wedged in between the lengths, sо as to form a compact mass. It is then put into the fire and lightly heated, receiving a few blows upon both faces as well as upon the edges.

It is next smeared over with a paste of clay and water, and when dried it is exposed first to a light welding heat, and after a slight hammering to a stronger heat, when it is vigorously and quickly beaten into four-sided bars about a foot long, and a finger's thickness. These are again heated, separated, and drawn out into square rods about J-inch broad on each face. These are then twisted from right to left, while the part which is to be twisted is heated to a red heat nearly verging upon white. This process is repeated by heating two or three inches at a time, and then cooling it with cold water, till the whole rod is converted into a fine screw, which is made as even as possible.

To make an Iran barrel six or eight rods are required. When eight are employed, four of them have the twist from right to left, and four from left to right. Every rod after having been slightly heated is lightly hammered on its two opposite sides equally, so that two sides have the threads beaten down, and the two others have the threads standing, and retaining their original roundness. Each rod is now made up of lengths of the same direction of twist, and is laid parallel to the other, so that rods of opposite twist are in alternate succession.

The steel having been formed into bars is now ready for manufacture into gun-barrels.

The extremities of the bars are welded together, and the baud or skelp is now ready for being formed into a hollow cylinder through being twisted in a spiral line upon itself, which is begun at the breech or thicker end, and continued to the muzzle. When the twisting is so far completed that the edges of all the twists stand even, and the cylinder is nearly equal, it is coated with a thin paste of clay and water, and is then ready for being welded.

A welding heat is first taken in the middle of the cylinder, and the edges of the twists are brought together by the breech being struck down upon the stone anvil perpendicularly for the purpose of jumping up the edges. The welding is constantly repeated, so that the twist, which was jumped up, is successively hammered when the heat is well on, till the barrel has been
welded up to the muzzle.

This process is then repeated, commencing from the middle to the breech, and afterwards from the middle to the muzzle, during which an iron rod is introduced at each end and used as a mandrel. A third heat nearly red is now taken at the whole surface of the barrel, which is then made regular and level by smartly hammering it. The barrel is then fixed horizontally through
a hole in an upright post and bored, after which its surface is filed, polished, and prepared for bringing out the damasked lines. " Jauhar " is brought out through biting the whole surface with " kasis," a sulphate of iron.

The barrel is completely freed from grease or oil by being well rubbed with dry ashes and a clean rag. About three drachms of sulphate of iron in powder is mixed with as much water as is sufficient to bring it to the consistence of thick paste which is smeared equally over the whole surface of the barrel, the muzzle and breech being at the same time carefully plugged. About two hours afterwards, when the metal has assumed a blackish colour, the coating is rubbed off, and the barrel cleaned as before. Barrels are called " pechdar" when plain or simply twisted, "jnulmrdar tvheu dunmsked" when damasked. For the latter the rods are disposed according to the kind of brilliant or damasked lines to be produced, called either from the country as "Iran" or Persian, or from the figure, as " pigeon's eye," " lover's knot," " chain".

The barrel is then smeared with a preparation composed of the same quantity of sulphate of iron and four ounces of water, and is hung up in the well. Every gunsmith has, in the floor of his shop, a well about two yards deep, the bottom of which is covered with a layer of fresh horse-dung half a yard thick. Suspended by a string from the cross stick at the mouth of the well, the barrel which has been covered with the mixture as before is taken out every morning and cleaned with dry ashes and cloth, and hung up for 24 hours with a coating of the solution. This process is continued for 20 days or a month till prominent lines are formed on the surface of the barrel, separated from each other more or less by other depressed lines or grooves; the former will be found to have the same direction as that of the thread of the screw in the twisted rods. The prominent lines when rubbed are bright and of a colour somewhat approaching silver, while the depressed lines are dark and form the pattern.

The " zanjir " or chain damask consists in the introduction of a band of prominent and brilliant lines disposed like the links of a chain between parallel plain lines of damask. The processes are the same as before described in cutting up the " pig," and in reducing the strips into straps, but the " pie " or " ghilaf " contains only eight lengths, which when welded is drawn out into straps 1/2 inch broad and 1/8 inch thick. One of these straps being heated is bent backwards and forwards upon itself in eight continued loops, each an inch long, and is then worked up into straps 1/3 inch broad, and 1/16 inch thick.

Three of this kind of strap are required in this pattern, one for the chain and two for the lines. The face of the iron anvil has a perpendicular hollow about one-quarter of an inch deep, and about one-third of an inch across. One end of the strap is laid while cold across this groove, and driven down into it by a small chisel and hammer, by which the strap receives a bend or angle. Its opposite face is then placed across the die near the acute elbow made by the chisel, and is in like manner wedged into it, after which the operation is reversed until the whole band is converted into a frill of loops. This frill is then heated, and the operator holding one end with a small pair of tongs brings two pairs of loops together leaving the ends open. This is continued till the frill is much reduced in length through the loops of the strap standing at right angles to its general direction. Different lengths of frill are welded together, so as to form a ribbon six spans long, placed in contact with two plain straps set on edge, and four rods, two on each side
twisting alternately, from left to right, and the reverse. The general band of these seven straps is then treated as that for the "Irani" damask.

The chain damask is in general preferred to all other varieties, excepting the silver twist. The Kashmiris still make blades for daggers in the same way, as one which was made for the author at Srinagar to fit an Indian jade handle is damasked, and Moorcroft relates that they made sword blades for him to order, though they did not usually manufacture them. It is said that "jauhar" is imitated in Hindustan by lines being traced in a coating of wax laid over the metal, and the barrel being exposed to the action of sulphate of iron.


We will now look at some pictures of barrels produced in India using such techniques. The first is an Indian matchlock with a herringbone pattern barrel:

(click image to enlarge)

The next is an Indian matchlock from the late 1700s with a beautiful Crolle-twist wave pattern:

(click image to enlarge)

The next is an 18th century Indian musket with a laminated steel barrel:

(click image to enlarge)

Note that while the barrel making technique in India was quite advanced in the 1570s, they were still using ancient matchlock firing mechanisms by the time Lord Egerton wrote his book in the late 1800s. In the next post, we will look at the manufacture of pattern welded barrels in Europe.

No comments:

Post a Comment