READING THE CHARTS
Charts for the powerfeed and thread cutting features are located on the inside of the
Lower Belt Guard.
Figure 40
shows a segment of the chart and a brief description.
Figure 40
. Rates given in millimetres and inches.
Please note that these charts reflect approximate apron movement per revolution.
1.
Millimetres per revolution.
2.
Gear layout for millimetres per revolution.
3.
Inches per revolution.
4.
Gear layout for inches per revolution.
5.
Gear position A (all numbers in the row to the right represent number of teeth on gears used here).
6.
Gear position B and C: combination gears listed as 125/127 or 120/60.
7.
Gear position D (all numbers in the row to the right represent number of teeth on gears used here).
8.
Feed rate selected for I.
9.
Feed rate selected for II.
10.
Approximate feed rates in inches or millimetres.
FEED RATES
Gearing for feed rates are detailed in
Figure 40
. In the example below we will be selecting gears for a
feed rate of 0.002” per revolution.
1.
Find 0.002” in the chart.
2.
Locate the number in row A, which is above 0.002”. The number is 24, representing a gear with 24
teeth.
3.
The number in row B above 0.002” is 120 and the number in row C is 60. These 2 numbers represent
one of the 2 combination gears supplied with your lathe.
4.
Finally, in row D you will find the number 120 that represents a gear with 120 teeth.
5.
Looking at the gear layout we see that gear A (24 teeth) meshes with gear B (120 teeth) and that gear C
(60 teeth) meshes with gear D (120 teeth).
6.
Move the
Feed Rate Lever
to the I position as described in the section titled
Feed Selection
.
Please note that the corresponding feed rate in millimetres would be 0.1 millimetres per revolution and
that the gearing is identical.
Chester UK Model B
26
