4471 Walden Avenue
Lancaster, NY 14086
Phone: 716.681.8222
Fax: 716.681.8789
Email: info@unitedsilicone.com

Hot Stamp Tooling

Tooling Components

A structure built on a shaky foundation will not withstand the test of time; neither will the quality of your decoration! Tooling is the foundation of any Hot Stamp/Heat Transfer Decorating application.

Hot Stamping is “the combination of Temperature, Pressure, & Dwell to transfer an image from a carrier to a part”. These three components are interdependent; a change or variation in one may affect/impact another.

Temperature - The amount of heat required to soften the foil or heat transfer pigments and the part surface to insure thermal bonding of foil/transfer to part.

Pressure - The clamping force required to insure full contact of die to part. The size of machine is identified by the size & location of artwork as well as the size of the part being decorated.

Dwell - The time that the die or roller is in contact with the foil/transfer and the part

The Pressure required for an application can be determined using the following guidelines:

Foil & Silicone Rubber Dies – approximately 350 pounds per square inch of die contact area (artwork size to be stamped).

Heat Transfers & Silicone Rubber Dies – approximately 500 pounds per square inch of die contact area (image size of transfer).

Foil & Metal Dies – approximately 1,000 pounds per square inch of die contact area (artwork size to be stamped).

Example:

Artwork Size = 3” x 7” or 21 square inches 
21 sq. in. x 500 PSI (HT w/rubber die) = 10,500 pounds 
10,500 pounds / 2000 (pounds per ton) = 5.25 tons 
5.25 tons of Pressure required for a 3” x 7” Heat Transfer 
3.6 tons required for Hot Stamp application with rubber dies 
10.5 tons required for same application with metal dies

Hot Stamping & Heat Transfer Tooling must withstand these conditions. A structure built on a shaky foundation will not withstand the test of time under several tons of pressure.

Nesting Fixtures are required to secure/hold parts while being decorated, support the stamping area & locate/position part for repeatability. Nesting fixtures should be manufactured to be user friendly – easy for automation or an operator to load & unload parts.

Nesting Fixtures are manufactured of various materials as dictated by the part shape, substrate, size & support requirements.

Aluminum

Lighter than steel, easier to handle
Easy to machine
Will not rust
Durable
Heat Tolerant

Cast Urethane

Ideal for contoured applications
Provides tighter fit than aluminum, PVC, nylon or Teflon
Not as durable as aluminum
Material begins to breakdown at temperatures of 120F

PVC

Machined to part configuration
Won’t scuff clear plastics or a high gloss finish
Not as durable as aluminum

Nylon or Teflon

Ideal for automatic part discharge because of low friction.
Won’t scuff plastics
Not as durable as aluminum

Steel

Offers the greatest amount of strength & durability
Ideal for high tonnage applications

Additional features are often added to a Tooling Set to make set-up easier and provide consistent, quality parts more quickly on a tooling changeover. Jackscrews can be added to the base plate to facilitate proper alignment of the nest to the die. Alignment Pins will assist in aligning the part to die on contoured parts or flat parts where position of the graphics is critical. Fixtures can also be designed to be mounted one way preventing a mismatch from die to part or stamping the graphic out of orientation. Part Sensorsinterconnected with equipment controls detect part presence & identify proper positioning prior to stamping. These devices are ideal in automated systems greatly reducing scrap rates.

Consistent, repeatable part placement with proper support for the decorating process that is easy for the operator to use. These basic elements will provide very serviceable nesting fixtures. Keeping in mind these basic requirements are essential for a successful Hot Stamp/Heat Transfer application.

In the not-so-distant past, Hot Stamp & Heat Transfer Tooling was manufactured only from actual parts and delivered 2-3 weeks after receipt of injection molds often resulting in production delays. Prototype parts (which often did not match production parts) were sometimes used in an effort to have hot stamp tooling & molds delivered at the same time.

With the development of new software packages and advances of CNC-controlled equipment, Hot Stamp & Heat Transfer Tooling Sets can now be constructed simultaneously with Injection Molds. An electronic drawing file is all that is required to initiate the manufacture of required decorating tools – Nesting Fixtures, Die Mounting Blocks, & Dies. Completed tooling will be matched to the First-piece Run utilizing production molds. Any “tweaking” required will be made at this time avoiding previously long delays in new product launches. Electronic files are kept indefinitely thus allowing for quick & easy duplication when artwork or part changes dictate.

Part Holding Fixtures make up only one half the requirements of a Tooling Set. The other half, the Die, is equally important. Hot Stamping/Heat Transfer Dies are produced to mate to the part while fixtured. These components should be manufactured together to guarantee a matched set.

Silicone Rubber Dies conform to surface variations inherent in plastic molded parts. Full graphic art & photographic capabilities assure accurate art reproduction. Rubber dies are available in flat, multi-level, and contoured configurations for diverse applications. Rubber Dies are manufactured from Machine-Engraved and/or Photo-etched Molds.

Durometer

Measure of rubber hardness as expressed on the Shore A Scale. Low durometers exhibit high-elongation properties and improve coverage on irregular surfaces. Rubber in higher durometers are more tear resistant and will withstand pressure with minimum distortion.

Dual Durometer

Two different rubber hardnesses molded together in levels. Usually a harder material is used in the face of the die and a softer rubber in the background. This construction provides a pliable belly beneath the stamping surface to help absorb variations in part, wall thickness, etc…

Texture

A texture in the rubber face helps redistribute trapped air. Ideal for vertical applications with large surface areas.

Crown

A convex crown (as little as .010”) in the rubber face of a die will assist in eliminating air entrapment. Ideal for vertical applications with large surface areas.

Metal Dies – Magnesium, Copper, Brass, & Steel offer excellent heat recovery properties ideal for high speed, vertical applications. Metal dies offer an embossed appearance to your finished part. Recommended for “soft” substrates such as fabrics, paper, polyurethane, etc… When selecting a die material for your Tooling Set, use the following guideline:

“Rigid substrate – Flexible, Rubber Die”

“Flexible Substrate – Rigid, Metal Die”

SILICONE RUBBER DIES vs. METAL DIES

  Rubber Dies Metal Dies
Materials Available Various for specific applications – high temperatures, quick heat recovery, & high strength Magnesium
Copper
Brass
Steel
Average Die Life Contoured – X
Flat – 2X
Magnesium – Y
Copper – 4Y
Brass – 18Y
Steel – 20Y+
Surface Variations (sinks) Will Compensate No Compensation for Sinks
Variation in Material Thickness Will Compensate No Compensation
Set-up Time Quick Process Lengthy Process
Pressure Requirements 350 lbs. Per sq. inch (HS)
500 lbs. Per sq. inch (HT)
1000 lbs. Per sq. inch
Temperature Requirements 100F > Metal
(approximately 300-400F)
100F < Rubber
(approximately 250-300F)
Dwell Time 50% > Metal 30% < Rubber
Decorative Finish Foil/Transfer lays on top of substrate Imbeds foil/transfer into surface
Price Initial Set-up/Mold Charge
Die Cost < Metal
No Set-up/Mold Charge
Magnesium - $
Copper – 2X $
Brass – 8X $
Steel – 10X $
Substrates
*indicates preferred material
ABS
Acetal
Acrylic
Polyamide (Nylon)
Polycarbonate
Polyethylene
Polystyrene
PVC – Plasticized
PVC – Rigid*
SAN*
UV Coating
Epoxy / Epoxy Coating
Polyurethane
Wood
ABS
Acetal*
Acrylic
Leather*
Paper*
Polyamide (Nylon)*
Polycarbonate*
Polyethylene*
Polystyrene
PVC – Plasticized
PVC – Rigid
SAN
UV Coating*
Epoxy / Epoxy Coating
Polyurethane*

Die Mounting Blocks act as a “connector” in the Tooling Set mating the decorating equipment to the stamping die. Mounting Blocks provide the support behind the die. Without this support, a die may deflect under the force of the machine causing a lack of pressure in this area. Traditional Die Blocks are drilled with mounting holes to match your equipment & tooling set. Variations of the Standard Die Block offer alternatives for mounting dies – Dovetail, Type Holders, & Magnetic.

“Quick-Change” die technology vastly reduces time related to die changeover and set-up. A Magnetic Die Block mounts to your machine allowing dies to be easily affixed eliminating the need for screws to secure the hot stamp die. Using pin registration, Quick-Change dies improve repeatability from die-to-die offering increased production and less down time.

When venturing into a new Hot Stamp/Heat Transfer project, remember that Tooling is the foundation of all decorating applications. Many factors impact a decorating project. Too often critical tooling required for quality, finished parts is overlooked. A structure built on a shaky foundation will not withstand the test of time; neither will the quality of your stamp!