With the wheels given in [Fig. 71] the dividend will be as follows:—

15  stud pinion
 60 quarter-inches in circumference of beam
900
   50  rack wheel
   120 stud wheel
  6000
    75 beam wheel
900) 450000 (500 mathematical dividend
4500  
    00
500
  7 = 1½ per cent. for shrinkage
507 practical dividend.

Having the dividend, it is only necessary to divide by the picks to obtain the change wheel required, or to divide by the teeth in the change wheel to obtain the picks which it will give, thus—

picks 507 = 39 change wheel change wheel 507 = 25⅓ picks.
13 20

The following are the wheels used by various loom makers:

Rack wheel.

Stud wheel.

Stud pinion.

Beam wheel.