Workshop/Assessment Task
Unit/Topic:
STS Performance Criteria:
AQF Unit & PC:
CNCCT1001
2.3
MEM12024A 1.2, 2.1, 2.2
MEM16006A 1.2
MEM07007C 4.2
MEM12006C 2.3
Cooltools
Student Name:
Teacher:
Class:
Date:
Time:
15 mins
Assessment Event:
Total Mark:
Calculating speed, feed
and depth of cut
/8
Q1 From the table below what is the fastest surface speed recommended to turn aluminium ?
Recommended surface speeds for turning
Material type
Meters per min (MPM)
Steel (tough)
15–18
Mild steel
30–38
Cast iron (medium)
18–24
Stainless steels
23-40
Bronzes
24–45
Aluminium
75–105
Brass
90-210
_105____MPM
(1 Mark)
Q2 Calculate the rotational speed for a lathe (n) if the workpiece diameter =20mm and the cutting
speed Vc = 30 m/min. (Steel)
n = Vc/ π x d
d= __0.02__m
π = 3.14
n=__30__/(_3.14_x_0.02_)
n=_____ 478 ____rev/min
(3 Marks)
Page 1 of 2
Workshop/Assessment Task
Unit/Topic:
STS Performance Criteria:
AQF Unit & PC:
CNCCT1001
2.3
MEM12024A 1.2, 2.1, 2.2
MEM16006A 1.2
MEM07007C 4.2
MEM12006C 2.3
Cooltools
Student Name:
Teacher:
Class:
Date:
Time:
15 mins
Assessment Event:
Total Mark:
Calculating speed, feed
and depth of cut
/8
Q3
When roughing a bar of aluminium we want to reduce the diameter in a bar from 25mm to 23mm
diameter in one cut. What is the depth of cut ?
Depth of Cut (d) = (Original Diameter Do – Feed Diameter Df )/ 2
d=( Do - Df )/ 2
d=(_25_- _23_)/2
(2 Marks)
d=____1.0____mm
Q4 From the table below
a) What feedrate should be chosen to cut aluminium as fast as you can?
__________0.75 mm/Rev
b) What feedrate should be chosen to get the best finish in aluminium?
_________________0.13 mm/Rev
(2 Marks)
Page 2 of 2