“I can relate our success in bringing tool-design and build inhouse directly to the hiring of our tooling manager, Mike Boyden, who oversaw the transformation of our tooling department from one focused only on tool maintenance and repair to a fully functioning tool and die builder,” shares Nelson. “When he came on board, it changed the way that we were able to do things here, including quoting. We no longer have to rely on contractors to supply tooling quotes.”Die Engineering a Differentiator
“Our engineering capability separates us from other stampers in the market,” Boyden explains. “And, we made a big leap forward in that area just a couple of years ago. That’s when we dedicated our effort to reducing new-tool-development time in the press and focused on improving our simulation capabilities.”
Improvement came on two fronts—people and technology. First, Nelson and Boyden turned to its youth movement, and the hire of manufacturing engineer Alex Jackson. A 2022 graduate (Bachelor of Engineering) from the University of Wisconsin-Platteville, Jackson represents what Nelson calls “very good bench strength. While he’s a degreed engineer, he didn’t come to us with any toolroom experience. But fortunately for us, he showed a great interest in learning die design and using our software systems, including SolidWorks and LogoPress.”
Almost from the start, Jackson took his knowledge with LogoPress DieDesign (software the firm acquired from Accurate Die Design Software, Inc.) and began to investigate simulation software. Ultimately, D&H again partnered with Accurate Die Design Software to purchase the Stampack sheet metal-forming simulation software package.
“Jackson sits right next to Boyden,” Nelson says, “and while we expected a rather long road for him to get up to speed with tool design, he almost immediately was able to design a small draw die. We still use that die as a training aid for students that we bring into the company, to learn about career opportunities in metal forming.
“From there he has taken off,” Nelson adds.
Solid and Shell Simulation in One Environment
“What really caught my attention with Stampack,” Jackson shares, “was the simulation using solid elements as opposed to other simulation software we looked at using shell elements only.”
As an example of the benefits of being able to design in shell and then also provide solid simulation, all in one software environment, Jackson recalls a recent project to develop a complex die for a deep-drawn stamping.
“We were able to use Stampack to verify that we would need a larger vertical radius on the part itself,” he says. “So, we went back to the customer and said, ‘We ran this through simulation and it’s showing significant failure in this one corner. Can we increase the radius?’”
Jackson adds: “I showed the customer all of the results from Stampack to show where the part was thinning the most during simulation, and how we could avoid the problem if we could design in a more gradual radius. Also, the simulation suggested that we would need to hold the part more tightly, because it had a pretty serious draft angle on it that created excess loose material. That opened up the possibility of a lot of vertical wrinkles. We designed in draw beads to pull out the wrinkles, since this is a class A surface-finish part, but we couldn’t hold the material tightly enough without first making a few design changes. Making the radius change solved the issue altogether.”
In the end, Jackson and Boyden conclude, the customer was very appreciative that the duo actually had some qualitative analysis behind why it wanted to make the changes. “And, once we put the redesigned tool in the press, we made good parts within just a few press strokes,” Boyden shares. “Without the simulation it would’ve probably taken two weeks and several trips to the press to finally get good parts.”
Describing how he leverages the benefits of both shell and solid simulation, Jackson notes: “I always start with shell, and then it’s nice to be able to run a quick simulation and make sure that there are no underlying problems that I can spot right away. I can get results in 10 or 15 min., sometimes less. Then, later in the development process it’s nice having the solid capability for the accuracy when simulating more complex operations such as deep drawing, coining or ironing.”
As an example, he recalls a part that D&H had been running for about 3 yr., when the customer asked if it could increase the size of a bearing-seat surface coined onto a part. “I honestly did not think this would be a difficult engineering change,” recalls Nelson. “However, simulating the design change in Stampack revealed that we didn’t have enough material to start with; it was a problem. Stampack’s simulation capabilities ultimately helped us implement an additional restrike station to improve the functionality of the part.”
Feature-Laden Software
Among the various features embedded in Stampack that the D&H design team appreciates: springback prediction with compensation; a trim-optimizer tool for automatically developing cutting punches/blank outlines; and a tolerance check to compare the resulting geometry from the part that Stampack forms to the CAD geometry from the original 3D part model received from the customer, aka the target model. In addition, D&H uses the Export to Simulation tool found in LogoPress DieDesign that extracts the surfaces required for a simulation and then automatically organizes them by station number into folders that it creates on the computer.
The firm has one floating seat of Stampack on its network that it runs on a dedicated computer. In addition, Stampack provides unlimited seats of free viewer software, which employs the same graphical user interface as the full program (but without any save or calculation capabilities).
“That’s generally what I’ll bring into customer meetings,” shares Jackson, “which they really seem to appreciate. The viewer in Stampack looks exactly the same as the result you’d see when running Stampack on the dedicated PC.”
Lastly, Stampack also includes a job-manager function that allows users to queue simulation jobs to run overnight or over a weekend. “We can even pause a simulation if we want to go into the file and make changes,” Jackson explains. “It will save all of the new information and restart the simulation at another time, if need be.”
Communication and Manufacturability Go Hand-in-Hand
Since D&H began using Stampack, the simulation software has become a tool employed in the engineering office’s normal workflow. The firm uses it as a critical component in its communication with customers.
“Communication holds the key to ensuring quick turnaround, accurate quotes and minimal tool-tryout time in the press,” Nelson says. “Designing and simulating in Stampack ensures that we don’t have to make last-minute changes—to either the tool or the part design—to ensure manufacturability. We’re always communicating with our customers, often on a weekly basis.” MF
View Glossary of Metalforming Terms
See also: Accurate Die Design Software, Inc., LOGOPRESS
Technologies: Software
