Th e c lassic examp l e . of rr,as s production is the
manuf acture of mot or cars. f·1ass product ion was first
brought to wide not i c e as Ford made innovat i ons result ing in great ly r e du c ed unit c ost in his product i on of " Mode l T " cars in t he e arly 20t b century. Ford ' s first as s emb ly
line was u s e d f or the manufacture of :wagneto s. With one workman doing a c omp l et e j ob , he c ould assemb l e from t hirty t o forty :t,) i e c e s in a nine-hour da;y , t hat is about
20 minut es e ach �a�net o. When the as s embly was sp lit int o twenty-nine op erat i ons , t he as s emb ly t iQ e was cut t o
t hirt e en minut es t en seconds. The height of t he l ine was rais ed e i ght inches , cutt in g t he t im e to s even minut es.
Fu�t her deve lbpment s cut �he t ime t o five oinut es p er
magnet o. As t he resu lt of such princ iples b e ing applied th::'oughout t t.e product ion pl�oc ess , t he cost of the
"Model T 11 f e l l from $780 in 1 91 0 t o $290 in 1 924 . ( 24)
In :rres ent -da;y p la_"YJ.t s manufacturing c o sts p er c ar have b e en relat ed t o output per y e ar.( 25 ) 'Ec onomies result t hrough use of more aut omat ed t o o ls for as s emb ly , reduction in init ial c os t s ( Qeve lopment ) per c ar , purchas ing e c onomies t hrough larger orders f or bought out mat erials , c omp et it ion
among such supp li ers and the reduct i on in p er uni t capi� al cos�. P�&t t en ( 26) has estimat e d t hese e c onomi es as
list ed in T ab le 2 . 1 f or a UK manufacturer produc ing a
s ingle :wode l at varying l evels of output o n one s it e.
Output ( thousands/year) 1 00 250 500 1 000
Init ial c os t s for mode l £m 1 5 20 28 38
C osts per vehic l e .
Init ial c os t s 38 20 1 4 1 0
Mat erials & c omp onent s
b ought out 265 250 240 235
Labour ( direct & indirect ) 1 02 90 86 83
C ap it a l c harges for f ixed
& working c ap it a l --60
_.22
50 --48Total e x-works c ost 465 41 3 390 376
Index 1 00 89 84 81
TAELE
2.1
I l lustrat ive est imat e s of C os t s and Sc alein car manufacture
21
When small vo lum e s of vehicles must be produc ed very di ff erent t echniques to tho s e of the large
manufacturers descri b e d abovs , must be used. Norbye
(27)
gives an examp le of a West G erman firm which sp ecialises in manufacture of sma l l vo lumes of sp e c i a l vehicles. The product i on of such vehicles is achieved eco:::1omicallythrou gh sp ecial t echniques and measures such as :
1 . Product ion machiner;y is quickly adjustab l e over a wide ra�ge ;
1 1 . St and ard machine t o o ls ( not sp ecial
purp o s e e quipment int ended for proc e s s ing grsat sr nu�b ers 1n short er t ime ) ;
iii.Us e of f ibreglass body pane ls ;
1v . Short , s low-moving ass embly lines ;
v. Us e of m odular des ign unit s and modular c onst ruct i on ;
vi . Us e of b ought-in engines , gear boxes and ot her c omp onents.
The aircraft as s emb ly industry was t he s c ene of the
dis c overy and quant =._ .:' i c ati on of the l e arning curve.
Studi es of aircraft ass emb ly showed that the fourth p lane
required only
80%
as much direct labour as the s e c ond ,the eighth plan only
80%
as much . as the fourt h and so on .(28)
.
Thus in aircraft as s emb ly , short product ion runsb e ar t he p enalty of additi onal l ab our cont ent per unit. It has b e en shown that l e arning rat e is proport i onal
to labour input p er lb of aircraft
(29).
Thus it wouldbe exp e ct ed t hat le arning c urves would be most apparent
in product ion. pro c es s es with high lab our c ont ent .-.
N everthe l e s s , Hirscbmann
(30)
has shown that t here isevidenc e to suggest that learring curves occur even 1 n a
f low-pro c es s indust ry , such as o i l refining.
Tt a u s e of m e as�Te s t o increas e the rat e of
l e arning of ass embly work ers as us ed in the e lect roni c ass emb ly industry was r eport ed by Young and Tanner
(31).
A syst em of modular product i on s t at ions was us ed t oprovide f lexibi lity t o m e et changing demands. They cl aimed a
35%
hi gher rat e o= s et-up us ing modular productionst at ions.