Here are step by step instructions on how to calculate 6 Figure and 8 Figure Grid References the Shaven Raspberry 1:25000 & 1:50000 Scale Pocket Grid Reference Tool.

Calculate a 6 Figure Grid Reference

Calculate an 8 Figure Grid Reference

In order to plot an 8 figure grid reference the 6 figure square must now be divided into tenths. It would be impractical to print 1/10th grid squares at this scale so the Shaven Raspberry Grid Reference Tool has the unique feature of dividing the square in half. The thin grey lines on the Roamer represent 5/10th divisions making it easy to estimate the last two figures of an 8 figure grid reference!