AUTOMOTIVE SECTOR: BOOMING, BRIDGING MACHINE TECHNOLOGY SPOTLIGHT: PRIVATE EQUITY GROUPS ARE COASTING, OR COPING? COMMUNICATION GAPS LARGE 5-AXIS MACHINING LOOKING AT MANUFACTURING Technology, market expansion 4 answers to NC post-processing Advancements enable Lots of money, no deals available in play key roles in the future of the questions for multiaxis equipment— manufacturers to create large, the metalworking industry—p36 Canadian automotive industry—p26 p30 highly complex parts—p34

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DECEMBER 2016

CMCover_Dec16.indd 1 11/21/16 10:48 AM New forms in punching

Understanding forming tools and their application, such as making a hinge, leads to more productive turret punching

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CFW_PunchingHingeForming_Dec16.indd 30 11/18/16 11:24 AM By John Ripka •The second forming stroke is added to all tabs to be formed. This forming stroke is determined liminating secondary operations in sheet by the amount of material needed to make the Emetal fabrication has been saving com- hinge and bends the tab up to a designed angle panies time and money for decades. The use of (see Figures 3a and 3b). The spring-loaded lower forming tools in a punch press has been elimin- assembly, or die, pushes the sheet off the lower ating secondary operations for the same amount insert before it advances to the next forming of time. location. The addition of simple forms such as extru- •The final forming stroke uses Hinge Tool 2, or sions, embosses, and countersinks to a piece of the knuckle tool, which curls the angled tab to sheet metal in a punch press can eliminate the form a hinge (see Figures 4a and 4b). This tool need for those secondary operations as well as reduce the amount of handling time for these parts. These all add up to reduced costs, or more importantly, increased profitability. More complex forms can also be produced in a punch press. Features such as louvres, thread forms, and tapped holes now are relatively easy components to create in a punch press. The newer tooling designs combined with precision stroke control of the latest punching machine help ease the creation of these more complicated forms (see Figure 1). Figure 2a—Hinge Tool 1 Figure 2b—This sheet shows produces the leading edge of the leading edge tab formed Creating Hinges in a Punching Machine the tab. with Hinge Tool 1. A hinge is an example of a more complex form that can be processed in a punch press without difficulty. With today’s machine technology, like punch presses with stroke control, hinges no longer need to be a headache to produce. By using a hinge tool on the punch press, fabricators can form many different types of knuckles with varying lengths and diameters. Metal enclosures and similar cabinetry that require hinges can be fabricated with integral hinge knuckles. Forming a successful hinge in a punch press is a Figure 3a—Hinge Tool 1 Figure 3b—This sheet shows process that typically involves two forming tools, applies the second hit and the bent tab at the desired Hinge Tool 1 and Hinge Tool 2 (also referred to bends the tab up to a desired angle formed with Hinge Tool as the “knuckle tool”), and three forming strokes. angle. 1. These forming tools are in addition to stan- dard punching tools used to create the tabs for forming. The process is as follows: •After the tabs have been punched in the sheet to be formed, Hinge Tool 1 is used to make the first two forming strokes. This first form pro- duces the leading edge of the tab (see Figures 2a and 2b).

Figure 1—Dozens of forms in many sizes can be Figure 4a—Hinge Tool 2 Figure 4b—This sheet shows made on a punching machine with today’s applies the third hit, which the rolled hinge formed with advanced forming tools. creates the rolled hinge. Hinge Tool 2.

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CFW_PunchingHingeForming_Dec16.indd 31 11/21/16 11:46 AM Figure 5—Hinge tooling can turn a punching machine into a high-volume hinge manufacturing workstation.

also includes a spring-loaded lower assembly to lift the material off the lower insert before advancing it to the next forming location. Forming hinges on the punching machine delivers some immediate benefits for any metal fabricator. The shop no longer has to worry about separate hinges, fasteners, spot welds, or other downstream assembly operations. Accuracy also is improved because manual labour is removed from the forming equation. Forming the hinge on the punching machine also eliminates the cost and maintenance require- ments for specialized press brake or stamping tooling. All this contributes to a much leaner manufacturing process (see Figure 5).

Additional Forming Tips Fabricators also should take into consideration the material they will be punching, its hard- ness and ductility. Both will have an effect on the result of the final form requiring press and tooling adjustments. For example, stainless steel is harder to form, especially in tight diameters.

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CFW_PunchingHingeForming_Dec16.indd 32 11/21/16 11:46 AM This requires reduced ram and machine speeds. and the tools were tested before being returned. Material grain direction also may have an effect The fabricator transferred the information for on the final forming result. Forming with the the hit locations to its part program and has grain may produce slightly different results been fabricating successful hinge components than forming across or against the grain direc- ever since. tion, requiring modification. Additional tips include a slower feed rate to John Ripka is an application technician with give the material more time to recover from Mate Precision Tooling, 763-421-0230, www. the previous form and to ensure accuracy of mate.com. the next form. A programmable dwell com- mand may be added to allow extra time for the material to form and strip properly from the tool. Lubrication also is essential, especially directly on the formed tabs to help them slide smoothly around the inside diameter of the knuckle tool; this is especially helpful in the production of stainless steel hinges.

Latest Forming Tool Resources There has been major improvement in how today’s metal fabricators under- stand and use forming tools in their punch presses, with hinges being a good example. Informational resources, such as CNC punching forums, blogs, and YouTube videos, have helped to spread the gospel about the usefulness of hinge-making inside a punching machine. Presses with precision stroke control have given fabricators the confi- dence to invest in this type of tooling. Even something as simple as a tooling manufacturer’s user guide can make a big difference. This type of document details the setup procedure for com- ponents and steps required to create a hinge form in a punch press, complete with screen shots and photos of the process. The troubleshooting section provides photos of hinge forms that are good and less than perfect with tips for correcting the form. Application technicians and spe- cialists also are available to assist fabricators when they purchase their hinge tools. A fabricator doesn’t have to troubleshoot an application alone. For example, a fabricator was having trouble creating good forms with a set of hinge tools. The forms were not con- sistent. After a series of phone conver- sations and email exchanges with the tool supplier, the tool was returned for evaluation. The stripper of the second tool (knuckle tool) showed damage consistent with the die being loaded 180 degrees off. The stripper was remade

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CFW_PunchingHingeForming_Dec16.indd 33 11/21/16 11:47 AM