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Beef Gut in Detail - Production Insights

I thought I would explain in a little more detail about how the anatomy of the cow intestine works, so players can have a further understanding of the process of making natural gut strings.

Below is an illustration of the four layers in the wall of the bovine intestine.

From inside:

I - Mucose membrane with finger-like outgrowths for enlarged surface area (“slime”)

II - Submucose membrane, firm-elastic layer mainly of connective tissue

III - Muscular layer, the circular internal one, the outside one longitudinal

IV - Serose membrane (blue) thin coating covering the abdominal cavity from inside and surrounding all organs

In cross-section, the layers are represented in the diagram below:

In processing the bovine casing for string production, the intestine is split lengthwise into ribbons. The ribbons can vary in width according to the needs of the string and when we order material from the supplier, we order the ribbons, or threads, by width and the width needed is determined by the diameter of string we intend to make. The wider threads go into thicker strings and the more narrow threads go into smaller diameters.

As the gut comes off of the splitting machine one of the workers separates the mucose and submucose layers from the muscular and serose layers, as can be seen in our video below:

The muscular and serosa layers are very tightly bound together. It is difficult, but possible, to separate these layers and it is my understanding that some makers in the past have done this prior to twisting the strings. However, we at Gamut Music are dedicated to reproducing historical strings — and no less an authority on string making is Marin Mersenne, who was quite clear about which layers of the intestine should be used in string making when he made the comment about the habits of string makers:

“But they soak them [casings] a day before winding them upon their pegs, so as to clean them and to draw off the fat and all that is superfluous, and so as to leave the membrane alone, of three sorts of fibers, that is, the straight, the transverse, and the oblique, from which it takes its strength…)

It is the three layers described in the illustration that correspond to the three layers that Mersanne specifies as being critical to the strength of a string.

Please be assured that we and our suppliers are diligent in continuing the tradition of making quality strings in the historical accurate way. When something goes wrong with a string, perhaps the material has something to do with it, but most probably, it is the string maker that has done something wrong. As we say in the workshop, “strings happen.”