By: Randy Kerkstra 26. June 2015

The Designer's Edge: Parting Line Bearing Surface

Coining that occurs from a lack of parting line bearing surface.

A lack of venting or closed vents causes maintenance and part quality issues. Today I’ll break down how parting line bearing surface impacts venting. Closed-off vents occur every day as toolmakers maintain thousands of molds, and in most cases this relates directly to a lack of bearing surface. Parting line bearing surface helps keep vents open, but it is often overlooked as a solution. The more bearing you have, the better.

Parting line relief used to be a standard process because of all the hand work required to spot a tool., but with today’s technology and being able to cut very close to true net, parting line relief is not a necessity.  Adequate parting line bearing surface reduces coining of vents, parting line burrs along cavity edges and stress on shut-off details that can break. I have a tool that has actually been coined in 0.025 over the years to where the vent relief channels where actually closed.

It would be beneficial to industry if it would focus on tonnage to square inches in relation to bearing surface. It boils down to the press tonnage and actual square inches of bearing surface on the parting line. I say “actual” because in many cases intended bearing surface is ground away by the toolmaker in the spotting process. You cannot just calculate the designed bearing surface when calculating tonnage per square inch. If you can reduce your tonnage per square inches by half, your coining will be cut in half.

I prefer zero parting line relief. For mold bases that have cavity inserts, parting line bearing pads should be used where the mold base outside the cavity is typically relieved. Moving from a 2 inch x 2 inch (4 square inches) bearing pad to a 4 inch x 4 inch (16 square inches) increases your bearing surface by four times. Although this may seem like basic math and logic, it is often not obvious.

Close up of coining.

Next month, I will move onto the venting of mold components.


By: Christina M. Fuges 25. June 2015

Another Moldmaking Resource

I'm always on the hunt for leads and new sources of moldmaking information like The Tool and Die Guy I posted about a couple years ago. I came across this latest one while milling around on the social media scene. It is called the It was created by Randy Hough, who has worked as a plastic injection moldmaker for more than 30 years and has seen moldmaking transform from a garage shop start-up into a highly technical complex operation. His mission is to provide real-life, useful tips, advice and how-to information that will enable the moldmaker to perform his task more efficiently and accurately. The site's emphasis is on user-created content, as well as tutorials and calculators. Check it out here, and perhaps you have something to share. Plus, they posted a link to our MoldMaking Matters: Your Career Can Make a Difference video! (a link right above the headline about Wire EDM).


By: Matthew Danford 24. June 2015

'Menu Pricing' Keeps Work on Track

An increasing share of work at Cavalier Tool & Manufacturing involves tight-tolerance automotive tooling. This particular mold is used to create an automotive fan shroud. (Image courtesy of Creative Technology Corp.)

One of the first things that caught my eye on the questionnaire that would eventually win Cavalier Tool & Manufacturing this year's Leadtime Leader Award was the shop's strategy for maintaining a consistent workload. This strategy involves keeping workload at 110 percent of total capacity, then outsourcing the extra 10 percent to trusted partners who are better able to handle portions of the build that are less cost-effective for Cavalier.

However, in the high-mix, low-volume environment characterizing a mold shop, things don't always go according to plan. Cavalier has certainly not been immune from the pain and disruption associated with customers changing designs mid-stream or requesting a much earlier delivery. Indeed, keeping jobs on track has required a different, complementary strategy: what company president Brian Bendig calls "Menu pricing." Essentially, Cavalier sets prices according to delivery dates (so, a 12-week mold will cost less than a 9-week mold).

For the shop, this approach minimizes disruptions by encouraging due diligence at the front end of a project. Yet, Bendig points out that customers can benefit as well. Essentially, he explains, the ball is in their court. Rather than giving out a number, the shop gives customers various options to work with according to their own pricing and schedule priorities. This strategy also helps facilitate the sort of close communication that’s so critical to understanding customers’ needs and desires, he explains. “Customers still need a price to see if we’re competitive, but they might not release the job for weeks or months. This allows them to tell us where they’re going to land. And if schedules change, we can accommodate, and they know what to expect in that event.” 

All that said, pricing isn't a chief concern for Cavalier, Bendig says. In fact, it's last on the list. Whether the shop is selling a mold or buying a machine, quality reigns supreme. Given its niche in particularly difficult work, this is a shop that can afford such an approach. To learn more about this and other factors that earned Cavalier Tool & Manufacturing this year's Leadtime Leader award, read this June-issue feature article

By: Christina M. Fuges 23. June 2015

Best Practices for Mold Cleaning

Mold maintenance is a big part of the mold manufacturing process. So much so, it is part of MoldMaking Technology's tagline: Engineer, Build, Maintain. Toolrooms across the globe are faced with mold dilemnas that can often be avoided with a little TLC, namely proper mold cleaning. I came across some very useful mold cleaning tips from Slide Products that I'd like to share.

These fall into the following five categories: (1) heat can help or hurt the process as various cleaning solvents have different characteristics and work differently at different temperatures; (2) there is a wide variety of cleaner formulations with varying characteristics; (3) the requirements of offline cleaners are primarily to dissolve resins, grease, oil, mold release and sometimes rust; (4) use a mold polish/cleaning compound; and (5) online cleaners are used to remove mold release build up, plate out of resins and light rusting of the mold while it is still warm and in the press. For more on each of these five items click here.

For an end user approach to mold maintenance, read a March 2015 MMT article by John Berg, Marketing Director from MGS Mfg. that outlines their systematic approach to mold cleaning.

By: Matthew Danford 22. June 2015

Above and Beyond the Call of Duty

ABCD award winners receive public recognition for their efforts. (Images courtesy of Dynamic Tool & Design.)

A big part of the article on Dynamic Tool & Design, winner of this year’s Leadtime Leader: Honorable Mention Award, covers the shop’s “culture of ownership.” Given that the company is actually owned by its employees through an Employee Stock Ownership Plan (ESOP), there’s a tangible aspect to this culture, but that’s not enough by itself. Truly letting employees control their own destinies (and that of the company itself) requires actually living that culture each and every day.

One notable example of the shop’s efforts to instill the right mindset is the Above and Beyond the Call of Duty (ABCD) award. Developed by marketing director Lori Phillips (who says she got the idea from a simple Google search), the award is given to employees based on feedback not from the shop’s management, but from their peers. That is, employees nominate one another to receive it, based on any activity or idea for improving the business that goes beyond their individual job descriptions. Winners receive a gift card and recognition on the “ABCD Wall of Fame” bulletin board, shown above. Here are a few examples of recent winners:

Keone Evans: When a key contact for mold qualification customers was absent one week, Evans proved ready and eager to shine. During that week, the mold setup technician answered to three different project engineers, each overseeing a vastly different tool running in a different press. “He successfully handled adversity, always presenting a positive image for the client while at times sacrificing his due personal time for the benefit of Dynamic,” says Eric Brueske, moldmaker, who nominated Evans for the award. “There are many in this world, myself included, who could learn a thing or two from this individual.”

Recent ABCD award winners include Keone Evans (upper left), Mike Olszowy (upper right), Ryan John (lower left) and Mike Wollenberg. 

Mike Olszowy: No specific instance led to Olszowy’s win, but that’s largely because there are too many specific instances to count. Indeed, judging by the nomination from Jill Lewis, executive assistant, Olszowy has developed a long-standing reputation for going above and beyond the call of duty. Dynamic’s systems engineer has been known to come in on Sundays to update computers, and to drop everything when someone has a problem.

“This past Monday, as Mike was walking in the door, my computer decided to stop working,” Lewis wrote in her nomination. “I figured I must have done something wrong, and felt bad for bothering Mike before he even had his jacket off.  Mike assured me I hadn't done anything wrong (Really!) and had it fixed in no time.”

Ryan John: One of the more cleverly stated nominations came from Kathy Boden, materials manager, who suggested that Ryan John, CNC programmer, receive the award for “doing an Awesome job in getting Better pricing while being very Conscientious and a Darn good guy to work with.” More specifically, “Ryan has been working with various vendors for months now trying to establish a better and cheaper way to purchase tooling to be charged against jobs and for general use in the CNC Department,” she wrote. “He has spent countless hours meeting with vendors and negotiating better pricing. He is making my job and, hopefully, others much easier and less time consuming in ordering tooling.” Boden also noted that John spent many hours implementing the shop’s tool vending machines.  

Mike Wollenberg. Dave Miller, company president, nominated Wollenberg for doing far more to troubleshoot a lathe than what would normally be required of a CNC lathe machinist. Wollenberg not only spent a great deal of time getting to the root of the problem, but also took on the task of dealing with the machine supplier to ensure that it would, indeed, be covered under warranty. “Mike … asserted authority and saved thousands of dollars in part cost that should have been covered,” Miller wrote. “Great job in looking out for Dynamic!”

If your shop has a similar program or even a similar philosophy, I’d love to hear about it. How do you show appreciation for employees and build the right kind of culture on the shop floor? Comment below, or send me an email

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