A JIG FOR PREPARING PUNCHED CARDS CARL 0. THOMAS University of Tennessee, Knodle, Tennessee
P u N c m n cards have found frequent and varied application in scientific problems. They have been particularly useful in this laboratory in the preparation of bibliography files. Cross indexing can be accomplished on one card, thereby reducing the total volume of the file. Also, the possibility of losing a reference through accidental misfiling is considerably reduced. A method for the preparation of punched cards from ordinary file cards has been reported by Begun.' With the simple jig used in this laboratory, one hundred cards can be prepared in about fifteen minutes. Nineteen holes are punched simultaneously along the upper edge of a 3- X 5- inch file card. The lower righthand corner of the card is then cut off to insure proper orientation of the card in the file. An exploded view of the jig is shown in the accompanying sketch. The jig can he built using ordinary hand tools and readily available materials. A powered drill press simplifies the work. To insure proper alignment the three parts labeled A are bolted together while drilling the guide holes for the pins. A wooden spacer is then placed a t positions B, a nail is placed in each guide hole, the strongback C is placed in position, and the assembly is again bolted together. The protruding nail points are cut off with a hacksaw and then filed flush with the bottom surface of the assembly. This gives each pin a flat tip and eliminates burrs. The cam lever (D)can be rough cut with a hacksaw BEGUN,G. M.,J . CHEM.EDUC.,32,328(1955).
VOLUME
34,
NO. 5, MAY, 1957
and then finished with a grindstone or file. The cam eccentricity is sufficient to give a stroke of about lip inch to the punching pins. A sturdy spring a t each position R lifts the pins after a card has been punched. The cards are properly positioned in the jig by the template E. A slot is cut in the wooden base (F) to allow the punched-out material to fall through. This jig has been in use' for several years and has significantly reduced the cost of maintaining a punched card file.