Thonging is a decorative way of securing or joining the ends of the pieces of the article together. A thong is a long strip of thin leather that is cut and used for thronging. The width of the thong varies depending on the size of the article to be produced. However, the common size is 1/8 inches while the size is further reduced to 1/10 inches if the article is very small. Leather to be used for thonging must be strong but thin. Usually, the type of leather used for the production of the article is used for the thonging provided it is thin. However, if a different colour effect is to be achieved, the leather craft man can dye the thongs. To create a continuous thong, the leather is marked in a continuous formation using a compass or any circular device.
Before thonging can be done, holes or slits have to be punched by the use of any punching device such as a six-way punch. Normally, a thin paper or card is placed under the leather to obtain a clean cut hole.
Also, after the punching, the punching tool must be twisted slightly before it is removed to ensure a perfect punching of the holes. The holes must be large enough to take the thongs. Therefore the size of the thong must be known so that the holes to be punched will correspond to it. The holes marked must be equally spaced usually ¼ inches from the centre of one hole to the next. A marked line can be created on the leather as a guide for the punching of the holes so that they would be straight.
It is advisable that corners of the articles for thonging be rounded so that the spaces, as well as the thonging, would not look ugly at the corners. If slits are to be created instead of holes, punch pliers are used. A very flat needle is used for threading the thong through the slits created.
The Thonging process
To thong two leather pieces together, the thong is drawn through the first hole on the top piece of the leather. It is cut and laid down inside the two pieces of leather between the thonging holes and the edge. It is then secured with glue. The thong is passed through the first hole again from the underside through both pieces of leather. The process is then continued, depending on the thonging technique. When the thonging is complete, the thong has to be fastened or secured. This can be done by threading the thong between the two pieces of leather just below the last hole. The surplus thong is cut leaving about ¾ inch end. It is then glued on the inside.
Another method is by deliberately letting loose the last few thonging stitches and threading the final end under them between the two pieces of leather. The thong is then drawn up tight and cut off on the inside. When a new length of the thong is to be joined together, the ends of both the old and new thongs are skived or pared down using a knife. The ends in opposite directions are slanted and a little glue is applied on the skived portions. They are then secured together and hammered to make them flat. It is essential to place a piece of card over the thonged area during hammering so as not to damage the surface quality of the leather.