This section is from the "Modern Machine Shop Construction, Equipment, And Management" book, by Oscar E. Perrigo. Also see Amazon: Modern Machine Shop Construction, Equipment, And Management.
The transportation of material or parts of machines being built, whether moved by shop railway, trucks, or cranes, becomes a charge on the job. In case of the use of trucks or the shop railway the machine rate, if we may so call it, has been considered already. In case of large traveling cranes, the crane is considered as a machine and rated accordingly. Where a man is required continually in attendance upon it his time may be charged to the fourth factor of cost. The same may be said of sweepers and such helpers as are sometimes engaged on general work not properly chargeable to any particular job.
Cranes serving only one machine are considered as a part of that machine and so charged in fixing the machine rate. Electric motors by which machines are driven should properly be considered as a part of the power plant, whether they are operating individual machines or line shafts driving a number of machines.
The cost of all repairs on machines should be kept and once in six months 5 per cent of the amount accruing during that time added to the machine rates. If the cost of repairs is comparatively slight the account may run through the entire year. If a machine is practically rebuilt a portion of the amount charged off for annual depreciation must be restored to its value.
In calculating the cost of power, lighting, heating, and ventilating we must not forget that if there are some buildings somewhat isolated from the main buildings of the plant they should be assessed somewhat more per square foot of floor area on account of the added cost of conveying power, light, and heat to them. These conditions should be carefully investigated and the burden put where it belongs. Unless the distance is considerable these variations of cost will not be very important, yet our cost system should show their influence.
While our cost system is primarily intended to show the actual costs of all work done, it does, if wisely administered, show us other facts equally important in the successful management of a machine shop or manufacturing plant. For instance: if the cost of a certain job is noticeably higher or lower than usual we may easily ascertain why it is so, as we may consider the five factors going to make up the actual cost of the job and find at once in which of them has been the loss or gain. It will be readily understood that a high priced man may be the more economical, as the time occupied on the job will be less and consequently the machine burden less, while the reverse will be true with cheap help.
We may also see that with the work plentiful and the charge for idle machines running up, there is something wrong in the department where it occurs, and apply the needed remedy. It will show us which department is the more efficient and turns out its work the cheaper. It will show which department is the more economical in the use of consumable supplies. It will show the relative cost of machine repairs in the different departments. It will show in any of the departments where new machines are asked for, whether those already in use are profitably occupied, and if not, we may investigate the reasons for their not being used and the advisability of their removal to another department, and possibly the substitution of a machine better adapted to the special needs of the work.
These conclusions cannot be so ascertained by any of the prevailing methods of averaging all or even the principal part of the factors that go to make up the total cost of the work done. By the use of the fifth factor, that of a proportion of extra burden on account of idle machines, we may get a good idea of what portion of the costs may be due to the fluctuations of business prosperity or depression. It may be argued that this system is intricate and expensive to administer. In proportion to the importance of the facts brought out this is not relatively true. If we really want the information in detail and in as accurate a form as the conditions will permit, we must pay for it in some way.
Often in the expensive school of sad experience we may know that something is going wrong, but we cannot assure ourselves of why, when, or where the trouble is located. By this plan we know all the facts worth knowing as we go along, and they cannot but be valuable aids in machine shop management. It will be noted that in this chapter we have not covered the matter of marketing the product, therefore the expenses of advertising and selling, as well as a proper percentage of profit, must be added to the costs as ascertained by this cost system in order to arrive at what shall be the selling prices of the goods manufactured. But as compared with properly ascertaining the actual factory cost of the product, this is a comparatively easy problem to solve.