Variously called thin plates or soft plates 1mm die cutting plates were first introduced around 30 years ago and have several benefits. Conventional 5mm hard cutting plates are in the region of 48 degrees Rockwell C hardness which is the same as the knife edge on cutting rule and this makes patch time quite consuming to allow an even cut and keeping the life of the die reasonable. 1mm plates are available in various degrees of hardness, by far the most common is 35 degrees Rockwell C therefore softer than the cutting rule. This degree of herdness was settled on as providing the optimum balance between the plate life, the die life and the make-ready time. This hardness allows the knife to penetrate into the thin plate and reduce the make-ready time whilst maintaining knife sharpness. Plates harder than 35 HRC defeat this object because they are too hard to protect die life as more pressure has to be used to achieive the cut unless additional time is made available for the patch up. 1mm plates are considered consumable items. The balance is between die life, minimum make-ready time and plate life. The most expensive item is usually the die, so die life is paramount, a low make-ready time desirable as downtime and labour are expensive, the 1mm plate is the least expensive and a consumable item. The optimum balance is acheived with 35 Rockwell C hardness.
An additional advantage is that creasing matrix can be left on the 1mm plate for regularly run job and stored with the die, again saving set up time and reducing material cost. Even large 1mm plates can easily handled by the operators.
1mm die cutting plates are used with thinner hard compensating plate, usually 3mm or 4mm depending on the make of press so that together they calculate the the original cutting plate thickness specification. The combination is much more cost effective than a hard cutting plate alone as the compensating plate has a longer life as it is never in contact with the knives. Hard cutting plates eventually show wear particularly in the first knife position.
We offer a full range of compensating plates.
We have 1mm die cutting plates, 35 HRC in stock in the UK for the following presses;
Bobst SP102E 1040 x 720 x 1
Bobst SP104E/ER 1074 x 736 x 1
Bobst SP106 Sprintera/Spantera 1090 x 761 x 1
Bobst SP106 Speria/Novacut 1090 x 736 x 1
Bobst SP142ER 1450 x 1028 x 1
Bobst SP145 Sprintera 1484 x 1064 x 1
Bobst SPO1600/160A 1640 x 1104 x 1
Bobst SPO160S/Vision 1640 x 1112 x 1
We can manufacture 1mm for most other types and sizes of press.
We can also offer all 1mm plates in both 20 degree Rockwell C and 48 degree Rockwell C as required.