COST ACCOUNTING AND ESTIMATING. 247 



ists in their particular line. For instance, it is very desirable to have the quantities for wood- 

 work, both carpenter and joiner, calculated by someone who has had practical experience in 

 this character of work; piping should be determined by an expert piping man. The ma- 

 terial is generally calculated in the same units as it is purchased — that is, steel by the pound, 

 lumber by the board foot, floor covering by the square foot, etc. 



The costs of construction bonds and insurance depend upon the time of construction 

 and the amount of the contract and are estimated on this basis. The cost of the trial trip and 

 delivery depends upon the horse-power, duration of the trial, size of the vessel and the point 

 of delivery, and where this amounts to a considerable item a detail estimate is prepared, tak- 

 ing into account the consumption of fuel, lubricating oil, stores, number of crew, commis- 

 sary, transportation charges, compass adjustment, docking, towboat charges, etc. In cases 

 where it does not involve a considerable item the cost is merely based upon similar vessels. 



The cost of plans is based upon the number of hours required in the draughting rooms, and 

 it has been found that the best criterion for determining these hours is the total hours of 

 direct labor for constructing the hull and machinery separately. Staging and launching de- 

 pend upon the size of the vessel and the duration of the construction period, and, based upon 

 these factors and the return cost of similar work, proper allowance is made for these items. 



The weight of structural castings and forgings is calculated after the sizes have been 

 determined from the registration rules. Practically all vessels are classified in one of the 

 society rules, such as the American Bureau of Shipping, Lloyd's, or Bureau Veritas, and if 

 not classified the scantling and sizes are usually obtained from the above rules. 



The structural hull is by far the largest item of cost and weight in the vessel, and it is 

 therefore essential that the quantities be determined with the greatest accuracy possible. 

 Coefficient methods have at times been adopted, but the use of such methods is dangerous, 

 particularly in the hands of the inexperienced or when a complete knowledge of their deriva- 

 tion is lacking. Usually the approximate lines are sketched, from which curves of shell 

 expansion, floor areas, areas of bulkheads, decks, and the length of frames and reverse 

 frames are obtained. From the above information and the scantlings obtained from the 

 Classification Rules, quantities are calculated in detail. The grouping is always done in the 

 same manner so that comparisons can readily be made. This is very essential and applies 

 to other jobs as well. 



The steel hull is calculated in three groups, each divided into regular classified sub- 

 groups. The first group consists of the continuous running members below the topmost 

 structural deck, namely, translversiei framing, longitudinal framing, keel plates, shell 

 plating, inner bottom plating and decks. The second group consists of the other members 

 below the structural decks and includes bilge keel, engine, boiler, and miscellaneous founda- 

 tions, transverse and longitudinal bulkheads, chain lockers, shaft alleys and miscellaneous 

 trunks and ducts. The third group consists of all the erections above the continuous deck, 

 including structural work for the poop, bridge and forecastle, bulwarks, casings, etc. 



The steel has been classified in the above logical groups in order that the result can 

 be checked by coefficients obtained from similar work. The quantities are net weight, cal- 

 culated in pounds, and are classified as to plsttes, angles, channels, bulb angles, half rounds, 

 tees, etc. The net quantities are transferred to the cost sheets and due allowance made for 

 wastage, to obtain the gross quantity or amount to be purchased. To these gross quanti- 

 ties current vmit rates are applied, obtaining thereby the estimated purchase price of this 

 material. 



The labor on steel, as in all the other jobs, is estimated in hours, being based upon the 



