DF—Double desk with one side arranged for type writer.
PF —Flat-top- desk with typewriter instead of right-hand bank of drawers.
R—Roll-top typewriter desk.
B —B ookcase.
RB—Revolving bookcase.
P—Coat tree.
X—Inkstand, single.
DX—Inkstand, double.
M—Letter tray.
MC—Map and chart case.
T—Table.
IT—Umbrella stand.
W—Wardrobe.
6. Application of the systek.—As most of this company's desks are made both with sanitary legs and with drawers to the floor, sanitary designs are indi cated by prefixing the letter O. Styles of desk or bookcase under each type are indicated by serial num bers. The length in inches follows the style number. Then comes the type symbol, and finally the number of the catalog (serially numbered) in which the desk is described.
Take, for instance, the symbol 03360DF8. To one who is familiar with this system it is at once ap parent that this refers to a, sanitary desk, style 33, ' sixty inches long, a double desk with one side ar ranged for a typewriter, described in catalog num bered 8.
This is not at all a complex system. It takes only a short time to become thoroly familiar with it. It tells all that is necessary in order to identify any product, and thus prevents indefiniteness and saves a great deal of time.
7. Use of numbers in, symbols.—Size is best ex pressed and most easily remembered as a numeral. A series of arbitrary numbers is suggestive of the relative size, not the actual. It is better, if possible, to use some characteristic dimension. This is more descriptive and allows the adding of new sizes in their logical order without disturbing the existing symbols. Where arbitrary numbers are assigned, a sufficient number of blanks should be left to cover all future additions.
In addition to preventing misunderstandings, sym bol systems save a great amount of writing on draw ings, requisitions, stock records and time-cards; many managers consider this saving in clerical labor the greatest advantage of a symbol system.
8. Symbols for manufacturing.—Symbol systems may be roughly divided into four classes covering: 1. Finished product.
2. Parts.
3. Operations.
4. Tools and machines.
The usual method of symbolizing the finished prod uct is to divide it into classes; .to designate each of these classes, if there are less than twenty-seven, by a single suggestive letter ; and to represent the different members of the class by consecutive numbers. Thus a certain line of presses may be grouped as follows: Class B—Berich Presses of all kinds.
Class C—Cutting, Horning and Wing Presses. Power, Single or Double action.
Class D—Drawing and Deepening Presses. Power, Single or Double action.
Class E—Embossing and Coining Presses. Power, Toggle or other.
Class F—Foot and Hand Presses—Lever Pendu lum Screw, etc., Single or Double action.
Class G—Gravity Presses, Drops, with Hand Foot Crank Belt over Roller Lifter.
Class P—Punching and Shearing Presses. Power, Throated.
. Class S—Stamping and Bending Presses. Power, Double-crank, Composite frame. Throated or straight, upright or inclined rectangular or round beds.
The individual presses are Cl, C2, C3, El, E2, W3, etc.
9. Improving this method.—A better method, how ever, wherever possible, is to make the symbol de scriptive, as are the chemical symbols, by combining a number of their elements. Thus there will be fewer symbols to remember and anyone can pick out the meaning of the combined symbol, even if he has not seen it before. The Derby Desk Company's system is of the descriptive kind.
There are two systems of designating parts. The older one numbers the parts of the finished model consecutively. If Pi is the model symbol, the part symbols would be P1-1, P1-2, P1-3. The great dis advantage of this system is that with an increase of interchangeable parts the same part used in two or more machines will have two or more symbols. This makes stockkeeping difficult and perpetuates one of the very faults the systep was designed to eliminate, the confusion of common terminology. Its advan tage is that the trade, in ordering repair parts, will not confuse parts of different models.