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Tablet Design:

A: Tablet Surface Area = Cup Area + Belly Band Area

Take the Cup Area x 2 (2 cup faces per tablet)
Next, take the Tablet Perimeter x Belly Band Thickness (Belly Band Thickness = Tablet Thickness – 2x Cup Depth)
Take step 1 step + 2 step = Total Tablet Surface Area

A: Tablet Volume = Cup Volume + Belly Band Volume

Multiply the Cup Volume by 2 (2 cup faces per tablet)

Next, multiply the Die Hole Surface Area by the Belly Band Thickness (Belly Band Thickness = Tablet Thickness – 2x Cup Depth)

Add Step 1 and Step 2 to calculate Total Tablet Volume

Tool Materials:

A: For Natoli to select the best steel type for each application, it is essential for tablet manufacturers to communicate their individual unique characteristics and requirements. Selecting the correct type of steel results in better product release, wear, and durability. Tablet quantity, sticking, picking, abrasiveness, cohesiveness, and product density are just some of the characteristics to consider when selecting a steel type.

A: All Natoli tablet compression tooling is made from very high grade, heat treatable tool steels.

Standard Steel for Punches is normally S7, S1, or 408 (Natoli’s Stainless Steel Grade).

Premium Steel for Punches is normally D2.

Standard Steel for Dies is normally D3.

Other exotic, less often used steels and materials are available for special tableting applications. Generally, to combat tool wear due to abrasive granulation, we recommend punch and die steels that are high carbon and offer superior wear resistance.

For more detailed information of the steels used for compression punches and dies, please refer to Section 4 of the TSM Manual.


Standard Steel
Standard steel for punches is S1, S7, or 408 steel (2-3% nickel – a bit softer and more flexible), while standard steel for dies is D3 steel (high carbon, high chrome). D3 steel has good wear resistance with common granulations. The premium wear material available for dies is carbide, where we insert a round cylinder of carbide into a protective sleeve of steel.

Premium Steel
Premium steel for punches is D2 steel. Due to the higher carbon content, D2 steel is harder and more wear-resistant. The downside to this is that steels with a higher carbon content are slightly brittler and therefore prone to breakage. The TSM book calculations for maximum punch cup force ratings allow for 20% less force for premium D2 steel compared with standard S7 steel.

You can expect to increase tool life by using premium-wearing materials, but be cautious due to the reduced compression force allowed.

A: If sticking and/or picking is an issue, Natoli suggests putting a couple of stations of punches made of 440C (stainless steel grade) and run a comparison between the different steel types. The 440C grade is superior with product release and may eliminate the problem.


S7 is the most commonly used standard steel for punches. The “S” in S7 indicates that it is shock steel because it is made to withstand high shock forces. The “7” refers to the chemical composition of the steel. Other grades include S1 and S5.

The “3” in D3 refers to the chemical composition. The “D” in D3 indicates that it is die steel. It is the type of steel that metal stamping and forming dies are made from.

It is a common misconception that punches and dies are manufactured from stainless steel. Although tooling can be made from 440C stainless steel, it is not truly “stainless” due to its carbon content, which is required for hardening. This steel is classified as corrosion-resistant but can still rust or discolor. All other steels used are classified as tool steel.

To better understand different steel types and their characteristics click the chart below:

Natoli Steel & Coatings ChartNEW-1
Natoli Steel & Coatings Chart

Tool Inspection System:

A: The TM-II maintenance program provides a comprehensive support program to ensure your success and keep abreast of the latest software enhancements.

Maintenance Program Features Include:

  • Unlimited Phone Support: Ensure your TM-II success with unlimited phone support to answer all of your questions.
  • Data CD with Natoli Tool Orders: Every tool shipment from Natoli includes a data CD for every tool being shipped complete with inspection data, drawings, and much more. This data CD saves you time because it downloads directly into your TM-II system.
  • Software Upgrade: Automatically keep up with the latest TM-II upgrades.

A: Workstation and Server Requirements:

CD-ROM or DVD drive for software installation and tool data. CD downloads require 800MB of free disk space (additional space may be required over time). Typical disk size of 2-4GB is appropriate for storing data and drawing files.

64MB memory
USB port for HASP key
Additional USB ports – number depends on type of inspections device selected and vision system interface.

Workstation OS Support:

  • Windows 98/ME
  • Windows 2000
  • Windows NT
  • Windows XP SP2 Home or Professional

Network OS Support:

  • Novell Netware 4.2, 5.1, 6.0 or higher
  • Windows NT 4.0 (SP6a or higher)
  • Windows 2000
  • Windows Server 2003

Database Engine:

Pervasive SQL V8 Workgroup database engine is required for application and is available for data if desired. For more information please visit the Pervasive website
Microsoft SQL 2005 database engine is supported for data management.

A: We believe there are three critical dimensions that should be included in a dimensional inspection of an upper or lower punch. Measuring any other dimension is either A) unnecessary because it rarely, if ever, changes and therefore is not worthy of the time and expense of measuring, or B) cannot be properly measured with current equipment and is better served by a visual inspection.

The three critical dimensions are:

  • Working Length: The working length is the most critical punch dimension as it determines tablet thickness and hardness. Tolerances should be determined by comparing the punch length to the length of the other punches rather than comparing it to a specific value. Uniformity of punch working length is the key. Therefore, as long as the punches are the same length (or within the specified tolerance of each other) it doesn’t matter how they compare to a specific, defined length.
  • Cup Depth: Determine cup depth by subtracting the measured working length from the measured overall length. Cup depth is not a critical dimension with regard to controlling tablet weight.
  • Overall Length: The overall length is not critical except that is is necessary to accurately calculate working length and cup depth. In other words, do not assume a 5.250″ overall length measurement for every punch.

Natoli Accessories:

A: 3600 R.P.M. Bench Grinder with 5/8″ shaft. The Retailer Shortcodes Fiber Wheel to polish the barrels, necks and heads. Unsewn Cotton Buff Wheel and White Rouge for the punch tips and cups.

A: Natoli Barrel Lube is fine for short-term storage only. For storage of six months or more, we recommend Natoli’s H-1 Tooling Storage Protectant. This lubricant is ideal for long-term tooling storage and has SAE 30/ISO 100.

Tablet Presses:

A: Running partial sets of tooling on a tablet press is very hard on the press and tooling because the machine’s overload system was designed to have constant pressure between the pressure rolls.

For example, if you are running four punches in a 16-station press, the system relaxes, allowing the rolls to come together. The next set of tools then hits the pressure rolls with a severe impact, forcing the rolls apart and shocking the overload system. This can cause damage to the system and promote hydraulic oil leaks. The punches and punch guides receive a severe shock when being forced through the reduced space between the rolls. This can cause premature guide wear or to become out of round.


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You guys are the best, thanks again. I always tell Dale how nice it is to deal with all of his people.

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