(commonly referred to as Clips)
Incomplete planchets are those discs of metal which are for one reason or another not as they are intended, in that they are always smaller than intended, and always not in the geometric shape as intended. The term clip or clipped planchet is often applied to this error, but is a term which is technically incorrect. However, the term clip is here to stay, and most dealers and collectors use the term regularly.
Planchets are formed after the blanks from the blanking press go through the upset mill, creating the raised edges necessary for proper striking. It is when the blanks are produced in the blanking press that the incomplete blanks can be produced.
The coin metal strip passes through the blanking press, with the blanks being punched out. If the coin metal is advanced at irregular intervals, or is mis-aligned, incomplete planchets can occur.
There are several types of incomplete planchets, which include curved, ragged, straight, corner and incomplete. This article will briefly explain the different types.
Curved - This is the most common type of incomplete planchet, and occurs when the coin metal strip is punched, and then advances less than intended, and another punch overlaps areas where previous blanks were punched. This will create a curved clip, with the curved missing piece actually being a part of the previously punched planchet.
Straight - These occur when the coin metal strip is slightly misaligned going into the blanking press, and some punches overlap the edge.
Ragged - This form of incomplete planchet occurs when the coin metal strip runs out, and the punches overlap the ragged end edge of the coin metal strip.
Corner - This very rare type of incomplete planchet occurs when the coin metal is slightly misaligned, and the punches overlap not only the side edge, but also a straight leading or trailing edge of the planchet strip.
Incomplete - This is commonly referred to as an incomplete clip, or incomplete incomplete planchet. Also very rare, this generally occurs when the blanking press is just starting up or winding down, and a punch not having enough pressure does not totally punch through the coin metal. When the strip advances less than normal, and another punch with enough force to punch through the metal occurs, the scar of the weak punch will be evident on the blank, the resulting planchet, and often on the struck coin.
The chart below is intended as a representative example of what might occur to cause incomplete planchets. In actuality, the planchet strip is up to 18" wide, and gang punches may have up to 80 dies to punch the blanks.
The numbers in the diagram are meant to represent 5 actions of the punch. The first, second and third are normal. The fourth punch has slipped (likely due to a loose guide), causing the punches to overlap the edge. The 5th punch also overlapped the edge, and overlapped the end of the strip as well. As you can see by the drawing, these various misaligned punches cause the incomplete planchets described above.