Time and Motion Studies 207 
standard limits on the parts which were to be fitted 
together, the total time of assembling governors was 
reduced to about one-third of the former time. 
A skilled demonstrator or leader needs to remain with 
the workers until they are able to do the tasks specified 
in the instruction cards, and within the time limits desig- 
nated. When a job has reached the stage where it is 
continuously done in the time specified, it can be safely 
left alone. Frequently, however, after considerable sav- 
ings have been made on work done by an experienced 
man or group of men, when a new man or group of men 
undertakes the same task, it takes a much longer time. 
Under these circumstances it is quite likely that the 
services of the demonstrator or leader will be again 
required. 
ALLOWANCES FOR EXCEPTIONAL CONDITIONS 
Where there is a difference in the quality of material, 
such as, for instance, in cast iron or cast steel, in which 
there are frequently as many as three classes of hardness 
recognized, a definite procedure should be agreed on 
regarding alterations in the surface speed and depth of 
eut to be used, together with the consequent results to be 
put in the time standards of the instruction sheet. In 
case there is a functional foreman in charge of the feeds 
and speeds, he would be the man to pass judgment on the 
quality of the metal. In case there is no such official, the 
foreman would be the man to make the decision. 
There should be no allowances made for the cleaning 
of a machine while the work is in process of being done, 
or of any oiling not specified on the instruction sheet. In 
case of delay for making a necessary repair, this should 
be approved by the functional repair boss, if there is such