Intricate Die Cutting
Specifications and Technical InformationPlease Note: All measurements below are in inches.
How to Select a Steel-Rule Die
The steel-rule die is critical in efficiently processing your production run.
• Savings – Buying a die configured for maximum printing efficiency costs a little more for the die, but reduces the piece part price for as long as the part remains active.
• Usage – For materials up through .020, laser-cut steel-rule dies will normally be used for die-cutting. For material over .020 matched tool sets are usually required.
• Prototypes – For prototypes where changes in the tool configuration might occur, the prototype quantity can be laser-cut using a computer-driven laser. This is in lieu of making a die that might be unusable for production quantities.
Tolerances and Standards for Steel-Rule Dies
Dimensional:
• Through .010 substrate thickness – plus/minus .005
.015 through .025 thickness – plus/minus .010
• Die-cutting to printing – plus/minus .005 to .010
• Minimum distance between rules – .070
• Minimum radius on steel rule die:
Outer perimeter of part – .032
On interior cutouts – .050
• Maximum variation where rules butt – .005.
• Flash or whiskering – cannot be visible at 24".
• Chipping or distorting of ink – None allowed.
Tolerances for Matched Tool Sets
• Dimensional – plus/minus .002
• Die cutting to printing – plus/minus .005 to .010
Tolerances for Laser Cutting
• Dimensional – .005
• Laser-cutting to printing – .010
Laser-cutting of polycarbonate produces an edge which has slightly charred look. On parts through .020 it is not a visual problem. (This charring is due to the carbon base in the material.)
Laser Cutting
Laser-cutting of individual parts may be recommended when:
1. Only a few parts are needed (e.g., 20 or less) and the cutting configuration is intricate and would require a fairly expensive steel-rule die.
2. The substrate is too thick for a steel-rule die (typically .020 or thicker) and it becomes a cost decision between paying a higher unit cost and laser-cutting the parts OR investing in a Class "A" hard tool.
3. Laser-cutting can hold a dimensional tolerance of + or - .005", and a laser-cutting to printing tolerance of + or - .010".
Note: Laser-cutting of polycarbonate produces an edge which has a slightly charred look. On parts through .020" it is not a visual problem. (This charring is due to the carbon base in the material.)
Class "A" Hard Tooling
This tooling is typically used:
1. When material thickness is over .020".
2. To cut tight dimensional tolerances of less than + or - .005".
3. On large volume production runs.
Class "A" hard tooling is relatively expensive and usually avoided unless needed to satisfy one of the above scenarios. The tooling consists of male and female die halves machined out of hard metal. The matched metal tooling operates by shearing the film. It can hold a dimensional tolerance of + or - .002" and a die cutting to printing tolerance of + or - .010".
Steel-Rule Die
The steel-rule die is the most commonly used method of cutting overlays because it is the most cost effective and meets the tolerance requirements in most applications.
The part's pattern is cut into a dieboard using a computer-driven laser beam. The appropriate steel rule is then forced into the pattern cut by the laser. A typical steel-rule die is mounted in a die press.
Tolerances:
• Steel-rule dies that are cutting substrates no greater than .010" can hold a dimensional tolerance of + or - .005".
• On material up to .025" the die can hold a dimensional tolerance of + or - .010".
• Die-cut to printing tolerance on a steel-rule die is + or - .015".
Other considerations with a steel rule die include:
1. Minimum distance between rules is .100".
2. Minimum radius on outer perimeter of overlays is .030".
3. Minimum perimeter on interior cutouts is .050".
4. Maximum variation where rules butt is .005".
5. Flash or whiskering can not be visible at 24".
Steel Rule Bevels
The die-makers use several different types of steel-rule bevels. The decision on the type of bevel and rule thickness to be used is determined by the following variables:
• Thickness of material being cut, specific die configuration.
• Type of die cutting being done (kisscut or cut through).
Note that one point = .014".
Bevel Designs
These include:
• Center Bevel (CB) – The length of the bevel is equal to the thickness of the rule, and both sides of the rule have the same bevel.
• Long Center Bevel (LCB) – Similar to CB, but ground to a longer profile.
• Side Bevel (SB) – All of the bevel is ground on one side of the rule except for a small back-grind of approximately .010".
For questions or clarifications call PPS at 913-791-9595 or toll free at 800-466-0626.
