Features

Ensuring Metal is Bent Correctly Off-Site

Bending is one of the most common sheet metal fabrication operations. Metal bending machines use pressure to deform metal into desired angular shapes to create custom design options with precise forming accuracy. With presses, benders, dies and extruders, tight forming tolerances and repeatable process control can form various complex geometries for bent metal panels and other building components. The right metal bending machine can accurately produce both large workpieces and smaller parts that require a higher amount of production with a quick delivery time.

Tips to successfully order bent metal panels with accurate sizing and profiles

By Mark Robins

Ordering systems like Bendex guide users through the process and highlight collisions, material availability, on-the-fly geometry checks and provide parametric parts for special applications. (Photo courtesy of MetalForming Inc.)

An advantage of ordering bent metal panels is they can be ordered in very large quantities and in long lengths. Ordering bent metal panels for construction also cuts down on on-site time preparing materials and allows projects to be completed more quickly. To fully optimize this process, it’s important that customers having their sheet metal bent off-site know how to best order from and interact with fabricators.

A Good Communication Chain

Generally, fabricators’ incoming orders for bent metal represent their clients’ needs and angle specifications. Product requirements determine the necessary size and profile to be ordered, ensuring that materials are not wasted and clients get the best value for their money.

To successfully do this, Brandon Reeve, president of Greenfield, Ind.-based Applied Fabricators Inc., stresses the importance of good and thorough communication among the metal fabricator, installer, architect and panel manufacturer. “We want to ensure that the design aesthetics remains, the system works according to manufacturer’s recommendations, it is easily installed and it does not exceed any fabrication limitations. The installer will need to provide accurate field dimensions and angles, which also meet his/her standards and techniques on how they want to install the metal. Fabricators should offer assistance with providing some standard shop drawings, and/or sketches of common profiles they can fabricate with the installer’s advice. A good communication chain, confirming all questions, answers, dimensions, angles, etc., should be written and copied to all in an email chain among everyone, so that all are on the thread. Often, it helps for difficult situations, to do a FaceTime, send pictures, and/or have the fabricator make a field site visit to help the installer achieve what he wants, that is still able to be fabricated.”

An advantage of ordering bent metal panels is they can be ordered in very large quantities and in long lengths. (Photo courtesy of Bel-Con Design-Builders Ltd.)

Mike Momb, technical director of Hansen Pole Buildings, Browns Valley, Minn., explains that to ensure metal is bent correctly off-site, it is imperative that accurate, to-scale drawings be sent to the fabricator. “These drawings need to include dimensions of every face, as well as any hems, degrees of all bends, and an indication of which side is the finish painted face. Quantity needed and length required should be included with drawing(s) as well as color selection. A return email with pricing should be requested. As these pieces will be bent on a press brake, human beings are involved in the process and any time a human is involved in direct manufacturing, fabrication errors can occur. Most often we see these errors where press break operators do not fully push trim into break before bending, resulting in non-uniform parts.”

“The ideal scenario is that all that information is transported and hold in the software platform and no additional intervention or manual transfer of data is needed,” says David R. Prokop, executive vice president at MetalForming Inc., Peachtree City, Ga. “When drawing and entering orders all data is immediately checked and prepared for production. Production papers and drawings are generated automatically, as well as the machine data and programs. Order confirmation papers as well as delivery information can be sent automatically to the customer or project manager.”

Crimp Curving

Shop curving of ribbed metal panels is done by a process known as crimp curving. “Crimp curving is the method of curving ribbed panels by gathering the material in regular hits or indentations,” says Thomas J. Carron, president of Floline Architectural Systems, Plainfield, Ill. “This allows for the panels to be curved in the strong direction creating convex (barrel) or concave (bowl) shapes. When ordering curved panels, the buyer should provide the panel radius and arc length of each panel that needs to be curved. In addition, providing the architectural design drawings is helpful. Prior to shop curving metal panels, review of the design drawings, shop fabrication drawings, and/or final structural steel fabrication drawings is critical to confirm that the panels will be curved to the correct radius.”

The FORMA Z32 Panel Bender can successfully bend metal. (Photo courtesy of CIDAN Machinery)

Ordering Success

One way to avoid communication errors that can occur when ordering bent metal, according to John Lawrence, vice president of technical operations at Applied Fabricators, is to beware of assumptions.

“The designer or installer detailing the profiles they need assumes the fabricator will know what they are wanting and can extrapolate any missing information and vise-versa. Not clearly labeling basic information such as ‘Am I looking at the front or back?’ of the part. I’ve seen complex profiles be fabricated correctly only to discover they are backward or a mirror image of what’s needed. Hand the information to a peer prior to processing and see if it makes sense to them.”

John D. Carron, vice president of Floline Architectural Systems, says commons errors in fabrication would include curving panels to the wrong radius. “This can be eliminated by properly measuring the curvature of the test panels prior to the main production run. Panel geometry and lengths are verified using AutoCAD software.”

Lawrence agrees that software and technology are aiding the process of bending metal correctly off-site. “We can now take a simple drawing and build a virtual 3-D model that we can simulate all the fabrication and perfect its design and manufacturing process prior to ever forming an actual piece of metal.”

“In 2021, when everything is moving towards full digitalization, Industry 4.0 and a smart factory setup, the key element is a software platform/solution that enables you to define and draw the needed parts off-site, guides you through the process by also ensuring you do not exceed material limits and part geometries that can’t be produced and assists with a user friendly and easy user interface so everyone can use the system,” Prokop says. “The highest level of accuracy and lowest level of errors and mistakes can be reached with directly integrated equipment. So, the online ordering system can send the production information directly to the different machines and eliminates errors made by re-typing each product.”

Ordering accuracy is key to having metal parts successfully formed off-site. (Photo courtesy of Floline Architectural Systems)