How to Make Dies for Hydraulic Press

Hydraulic presses serve as the perfect bridge between industrial blanking processes and hand sawing. They allow users to produce identical pieces faster than they could ever shear them, and create shapes impossible to be cut using shears alone.

Create a model of the form you intend to produce and adhere it to a flat base material, such as pipe or pasticene. Mask off the outer perimeters with tape, and cover them with release agent supplied with Devcon B.

Design

Die forming is one of the few techniques metalsmiths have available them for producing limited edition hollow, sculptural forms without them looking overly machine-made. Compared with raising or chasing, die forming can be completed quickly and relatively inexpensively while offering much softer curves than could ever be achieved through repoussage.

Die-forming with a hydraulic press is easy. First, select the shape you'd like your die to take; make sure that its larger than desired finished work and has enough extra room all around for a "flange" of metal to form around its edge after pressing, so it can later be cut off and used again when casting or for another purpose - its depth depends on how deep your piece needs to go into production.

Temporary dies made of masonite or plexiglass are good solutions when making multiple identical pieces at a lower cost, though these won't last for ever. For more permanent dies, Devcon plastic steel casting may provide the answer; just add a drop of oil when casting to prevent sticking.

Once you've created your die, use the release agent provided with your Devcon kit to lubricate it with. Place your model inside a container such as a section of pipe or metal flask used for casting rig casting; use more release agent on both walls and pattern to help stop Devcon from mushrooming on top and side edges of container.

Place the female die in a strong container with a metal band around it to prevent it from shattering or cracking when applying pressure to your hydraulic press. Next, create a male die from 18 or 16 gauge sheet metal by centering your design cutout on it and carefully scribeing a line around it; saw out your outline ensuring to stay within this line; cut away at it carefully using saws; saw out and file away at its sides until it matches up perfectly with its original state; file back to meet up with this process until all sides remain parallel and perpendicular sides are maintained!

Fabrication

Die are tools used for molding, shaping and stamping metal into its final form. Die can produce very large numbers of identical shapes more rapidly than saws can; and can form metal into shapes which cannot be cut with shears alone. Dies also have the added advantage of minimizing scrap metal when compared with hand-operated shears that may leave mushroomed ends behind.

Die working components are attached to a block known as a die shoe or, for larger dies, a die set or bed (see introductory photo and Figure 1). Both must be machined so they are parallel and flat within an acceptable tolerance; most commonly this is accomplished using grinding or milling; but in certain applications a die may also be constructed out of wood, plastic or Flexane composite materials.

Heel blocks are precision-machined steel blocks attached by screws or dowels to upper and lower die shoes that serve to absorb any side thrust generated during cutting and forming processes. Heel blocks become particularly essential if force generated is uni-directional and could cause guide pins to deviate from their positions, potentially misaligning critical cutting/forming components and leading to misalignments of critical cutting/forming components.

Producing a conforming die is more complex than creating a simple silhouette die, but its results may make the extra effort worth while. First create a model of the shape you intend to form; attach this model to a flat base material like masonite or plexiglass using masking tape as "retaining walls." Coat the matrix and its exposed face with release agent such as Devcon Plastic Steel Liquid-Type B or flexible rubberlike urethane such as Flexane 94 for optimal results.

Position the model over one of the plates, carefully scribe a line around it, saw out its outline carefully while maintaining straight edges perpendicular to faces and file up to it for smooth surfaces and tight tolerances. This cutout becomes part A on Diagram 3. Now center over another plate and saw another matching shape into it to complete part B on Diagram 4 as part A on Diagram 5. This completes one half of your die.

Tooling

Basic tools needed to construct a hydraulic press brake die are a matrix and punch. The matrix serves as the impression part of the die that molds metal; this should be constructed of non-rusting materials such as plexiglass, wax wood or plaster. A 2 inch die should have approximately 1-inch depth matrix. Any shapes to be produced must also be clearly marked onto it - sketch them out first on paper then transfer to matrix.

The punch, or male part of a die, should be constructed from a block of brass or steel that measures at least 3/8 inch larger in circumference than the form being created. Lubricate this component with silicone or release agent prior to starting work on your design.

To create a conforming die, you will require a model as a guide. It should represent an outline of the form to be created without undercuts and sharp bends; if the form will be reversible it should also be perfectly symmetrical; any texture or detail will need to be added through chasing later.

If you are creating a V die, its opening can be determined using what's known as the Rule of 8. Multiply the thickness of your material by 8 and select the die width that fits closest.

If you are making a matrix die, start by marking its silhouette onto a brass or steel plate, drilling and sawing out at an unstrained point, saving the sawed plate that will become part of the lower die. Filing away any round edges after sawing will complete this step - this step must be performed precisely to maintain perpendicular sides with extreme accuracy if wear and tear will wear down over time! Alternatively, professional companies are available that can create dies for you; but costs could become prohibitive.

Testing

Die testing is an integral component of ensuring accuracy and quality before production begins, providing an opportunity to correct any inaccuracies that could save both time and money in the long run. Furthermore, testing dies also reduces reworking requirements during mass production - saving both time and resources on full scale production lines. A die spotting tryout hydraulic press can be an excellent tool to verify die accuracy or molds before starting work - helping increase work efficiency while cutting costs significantly.

Hydraulic presses can also be used for shearing metal into strips with extreme precision and accuracy, offering more precise shearing than mallets or wooden punches while using less muscle power than their alternatives. When shearing with hydraulic presses, silicone grease or another suitable lubricant should be applied between die and punch in order to facilitate faster shearing processes.

Beginners to die forming should begin with creating a simple silhouette form, which can be done by cutting an oval out of heavy-gauge metal and backing it with plexiglass. Place this model in a matrix die with an outside steel pipe serving as its "retaining ring." When complete, cover all surfaces with plasticene sheeting before adhering it down using masking tape on flat base materials.

Conforming dies are special types of matrix used to produce contoured forms by bending. To construct one, start with annealed 26-gauge copper sheet that is at least 3/8" larger all around than the shape you want to form; make a punch out of plastic steel; and attach it securely with doublestick tape (carpet tape works well).

Shears are small punches used in hydraulic presses for shearing metal more efficiently and quickly than beating with mallets. Lubricated with silicone or another product to prevent mushrooming or damage caused by press pressure.