Machinery startup Ripple Engineering adds two rotational molders to the industry

Four years ago, Ben Ismert began a mission to double the size of the global rotational molding industry over the next 30 years. While Ismert hasn't hit that target yet, the founder and president of Ripple Engineering LLC is making progress.

With Ripple Engineering, Ismert has been chipping away at that goal with what the Kansas City, Mo.-based machinery startup calls "pressure-cooled rotomolding," a process that boasts shorter cycle times, improved impact strength and reduced warping compared with traditional rotomolding.

The controlled cooling cycle enables predictable and controllable shrinkage, he said.

"Cooling is where you get all of your advantages," Ismert said in a phone interview. "It's where you get your warp control. You get higher impact strength and the reduced cycle time, which, yes, it's the shortest part of the cycle."

But the key to all of those benefits, Ismert said, is that the internal vent opens automatically during the cooling cycle to circulate high-volume chilled air throughout the interior of a newly formed part.

On current models of the Ripple Engineering machine — now available in three standard sizes — the oven and mold rotate together. The machine also uses active venting technology, where it automatically equalizes the pressure between the inside of the part and the surrounding atmosphere during the heating stage. This eliminates the potential for blow holes and thin spots at parting lines and removable inserts.

The active vent can also be programmed to hold a specific pressure inside the part during the heating cycle after a layer of material forms on the inside surface of a mold, which can reach a maximum temperature of 650° F. This can improve a part's surface aesthetics and potentially improve its strength characteristics, Ismert said.

It also opens up the possibility for molding engineered resins beyond polyethylene.

At Ripple Engineering's 10,000-square-foot facility, the company is testing the ability to mold additional materials such as polycarbonate, acetal, polypropylene, nylon and others.

"We're molding those in our shop on our prototype machine for some of those resin distributors or resin manufacturers in hopes to connect them with potential new markets — a new market of rotational molding vs. only doing extrusion or injection molding," Ismert said.

"Polyethylene is fun, but I really want to introduce new materials into the rotational molding industry to expand it," he added.

That's a longer-term venture for Ripple Engineering, but all of these combined attributes are designed to underscore the company's motto of shaping the perfect part every time.

"We've shown that we can create an environment that's controllable, that can mold engineered materials, and we've simplified it enough where anyone can do it," Ismert said.

This month, the company delivered its second machine to a customer in Chicago. Ismert could not disclose the customer's name but said the company is a first-time rotational molder.

Last year, Ripple Engineering delivered its first rotomolding machine to its first customer: Striem Co., which makes oil separators, solids interceptors and chemical waste tanks in Kansas City, Kan.

Striem was established in 2015 — the same year as Ripple Engineering — by two of Ismert's brothers, Gabe and Vince. The company was formed when the pair purchased the oil separator, solids interceptor and chemical waste tank product lines from Schier Products Co.

Ismert previously served as president of Schier Products. His experience at the company, which included learning the limitations of traditional rotomolding, was a catalyst for launching Ripple Engineering.

"They are first-time rotomolders. They market rotomolded products and would purchase them from a molder near them," Ismert said of Striem. "They own their own tooling, but they were having quality problems."

For the past six months or so, Striem has been using a Ripple machine to mold cover adapters that are bolted on top of the tanks. The high density polyethylene covers can be molded in 71-72 minutes on average, depending on the ambient temperature outside.

"The part we are making, it's kind of a complicated geometry," Matt Keen, Striem's workshop manager, said in a phone interview. "It's not the easiest part to figure out, but when it came to Ben's machine, we were able to get it dialed in very quickly."

Keen, who is also new to rotomolding, worked with Ismert for nearly two months to learn the ins and outs of the machine and the various settings.

"There were a lot of variables involved," Keen said. "It was a process for sure, but it wasn't a very hard one just because of the way the machine is set up. It has so many different settings on it to where you start to figure out exactly what a certain setting will do to the plastic in that tool."

There were a few issues, with it being Ismert's very first machine, including some glitches with programming and mechanical problems with the vent design, but they were quickly resolved thanks in part to remote monitoring capabilities, Keen said.

Now, once you get a part dialed in, you simply save those settings as a recipe and "press play," he explained.

"We load up the plastic in the tool, and we press play every day on that certain recipe, and we get the exact same part every time," Keen said.

Ripple Engineering's first five machines are going to customers at a discounted price, Ismert said. Despite the close relationship, Striem did not get an additional family discount on the Ripple machine. Ismert declined to provide an exact figure but said it was a "significant investment" by the company.

"We've made good progress in the fact that we've designed and built two machines that can mold a perfect part every time and do that with higher-end materials," Ismert said of his company's mission statement.

"What we've already shown is our first two customers, our first two machines, went to people who were not molders, so we've already expanded the number of [rotational] molders out there by two just with our first two machines. And they're taking it up a notch."