Fishing and Gear Technology (2+1) copy 1

5.5.Tailoring/cutting of webbing

Unit 5 - Construction of netting/webbing

5.5. Tailoring/cutting of webbing
In certain types of fishing gears, the webbing has to be tailored considerably to acquire the required shape of net especially in trawls, seines etc. Braiding is not feasible when large scale manufacture of nets is needed as it is time consuming as well as uneconomical. In this case, machine made webbings are cut to required shape with minimum wastage. To accomplish this, proper methods of cutting are to be followed.

Methods of tailoring
Point – Bar system: Each mesh consists of four bars (legs) and four points (knots). There are two ways of cutting a mesh.

• Point cut: Cutting of 2 legs in each knot. All point cut gives a right angle webbing
• Bar cut: Cutting of only one leg at each knot. This results in a right angled triangular piece where the two sides are equal.

Tailoring rates:
Varying degrees of taper in the webbing is brought about by a combination of point and bar cuts. If ‘N’ is the number of meshes at the base and ‘L’ the number of meshes in height of a triangular webbing, the number of points (P) to be cut is (L-N). The number of bars (B) to be cut is always (2N) irrespective of whether point cut is included or not. Therefore to have a triangular webbing having ‘N’ meshes at base and ‘L’ meshes in height the calculation is as follows:

Where,
P - point cut
B - bar cut
L is the number of meshes in the depth of the webbing
N is the number of meshes in the longer side of the triangle