By Brad Ruppert
It’s funny how things happen sometimes. What started as a search for answers has resulted in a new alternative for the powder coating industry. DeGeest Steel Works, established in 1976, is a metal fabrication company located in Tea, SD. With a focus on large steel production weldments for original equipment manufacturers (OEMs) across multiple industries, the company knew it needed to bring automation to its finishing process for greater efficiency and to eliminate a growing bottleneck in production.
Having already made a significant commitment to robotics for welding, it seemed like tapping into the expertise of some of the same companies that supply automated welding equipment was a good place to start. However, conversation after conversation led to a dead end.
“We work with many OEMs, and between them, they have literally hundreds and hundreds of different parts we could paint,” said Derek DeGeest, the third-generation president of DeGeest Steel Works. “With all the upstream automation improvements we had made, we needed a way to multiply the efforts of our finishing department to keep up with increased production demands.”
It seemed the best option on the table was to take DeGeest’s highly skilled finishers away from the paint line so they could learn to program a finishing robot. With each new part, it could take up to a few days to create a new program offline and as much as a week or more on the production line to fix and fine-tune it.
There Has to Be A Better Way
Feeling frustrated, DeGeest and his team looked beyond the obvious suppliers and started to scour the internet in search of a better alternative. One company stood out as a viable option worth exploring – Lesta. Based near Milan, Italy, Lesta claimed it had self-learning robots that would mirror intricate human movements without having to rely on offline programming or a teach pendant (a handheld device used to program industrial robots).
“It honestly seemed too good to be true,” said DeGeest. “They claimed the robot actually recorded the precise movements made by a human finisher during a weightless learning mode right down to the exact spray technique. Then the robot repeats those movements on subsequent parts. It checked a lot of boxes for us in terms of what we were looking for. We knew we had to check it out.”
Lesta was founded in 2010 with the intent to change how people think about industrial painting robotics by making automation technology more accessible to manufacturers of all sizes. Because Lesta had a proven track record across Europe with over 400 self-learning robots in use, DeGeest and his team visited twelve of their liquid and powder installations. They ranged from a custom paint shop doing small lots of parts to large manufacturers painting large components.
Self-Learning Robots for Any Size Manufacturer
It didn’t take long for DeGeest to see that Lesta robots were truly different.
They were designed to be self-learning, and they were able to be used by any size manufacturer. They also stood apart because Lesta specializes in finishing.
Whereas other robotic solutions involve complicated programming, Lesta relies on the expertise of seasoned finishers. It takes into consideration the importance of the human eye and intuition that comes from years of experience, such as seeing missed spots and overcoming Faraday cage effect.
The Lesta solution gives the finisher ownership and responsibility for the line because it’s their program, taught from their knowledge and firsthand visual experience. Finishers have the power to fix, improve, and make the system better through higher engagement.
Instead of offline programming or teach pendants, Lesta robots are “programmed” by the finisher while finishing the part at hand. To start, every motor in the robot is disengaged – a process that takes only seconds. Then the finisher takes hold of the spray gun mounted to the robot and finishes the part as they normally would. During this free-float, weightless learning mode, the robot records all of
the finisher’s movements – right down to the subtle variances in gun angles, part coating sequence, and trigger pulls. This technology provides peace of mind from knowing each part will be painted consistently and with the excellence of a seasoned finisher.
The Lesta robot actually records the precise movements made by a human finisher during a weightless learning mode right down to the exact spray technique. Then, the robot repeats those movements on subsequent parts.
A site visit to a large powder coating operation in Sweden illustrated the process. The plant manager led the DeGeest team on a tour of their large finishing line. “There were hundreds of parts hung in batches on the continuous conveyor that snaked around the corner. It seemed endless,” recalls DeGeest.
The group watched the Lesta robot automatically switch its powder coating programs between parts and add powder to the corners and flange legs before it passed the reciprocators.
Then one of the operators squeezed past the group, stopped at the Lesta control cabinet and tapped the touch screen a few times. He opened the gate and walked into the robot area, picked up the control handle, put it on the robot and waited for the next batch of parts. As soon as the first of the new parts entered the area, he effortlessly moved the powder gun and began coating the edges and corners.
When he was finished, the operator brought the robot back to its start position and clicked a button to lock the robot’s motors. He removed the handle, gave the group a nod and walked away. The Lesta robot began automatically powder coating the next part without a gap in the line. “I remember thinking, ‘That’s it? He’s done?’ He was only in there for about thirty seconds,” recounts DeGeest.
DeGeest initially purchased two Lesta painting robots for DeGeest Steel Works. That quickly turned into six robots, which made a significant impact in the company’s finishing capabilities. The turnaround was so drastic, DeGeest formed a business partnership with Lesta to bring this technology to North America under the name LestaUSA. “The goal of LestaUSA is to work together with our customers’ trusted equipment partners to provide turnkey robotic finishing solutions. This technology addresses the challenges general industry manufacturers have during the finishing process,” adds DeGeest.
More Than Powder Application; Robot Also Eliminates Moisture Prior To Finishing
Another issue many in the powder coating industry struggle with is moisture. Prior to powder coating, moisture must be removed before the part enters the finishing stage. If it isn’t, there is a risk of defects. Sometimes, traditional dry-off ovens aren’t enough, as stubborn pockets of water often pool in hard-to-reach places.
Typically, the only three solutions to eliminate moisture have been to assign someone near the dry-off oven to physically blow off each part, turn up the dry-off oven temperature (which adds to energy costs and quality issues as the evaporated water leaves a concentration of chemicals that can affect adhesion), or re-engineer parts to have more effective drain holes. Lesta robots are available with a suction/ blow-off attachment that will efficiently eliminate excess moisture in seconds. The suction/blow-off functionality is programmed the same way as for powder coating – a person teaches the robot how to suction out or blow off any standing water after the pretreatment stage. The robot then “learns” those precise movements and repeats them – usually in less than one minute.
Making the Technology Work with an Existing Line for Powder Applications
Powder applications are easy to program for operational efficiencies. An advantage of Lesta robots comes from being able to have a program ready for the next part without a gap in production.
Since many manufacturers will need to incorporate Lesta technology into an existing line, two accessories are available to make such applications seamless. First, the LeCrob Production Manager can be used to take an existing conveyor and make it “smart.” It allows you to load a part and scan it into the system. An RFID tag on the conveyor with the part then passes a reader, which relays the information so the robot will run the program set for that specific part.
The LeCrob Production Manager can also store part process instructions, notes, and pictures to display on screens at hanging stations, prep & masking stations, and packaging stations, providing clear visual instruction to the operators. This not only helps maintain consistent part presentation to the robots, but also documents and delivers consistent quality parts from the entire system.
Another accessory available is Synchro, which synchronizes the robot’s movements with the movement of the conveyor. This allows coaters to create programs in a self- learning mode while a part is moving. Another key feature is that Lesta programs can adapt to changing line speeds, allowing the flexibility to run different parts at different line speeds.
A FABTECH 2019 Debut
After a lengthy process, Lesta robots were officially approved for use in United States factories after passing ETL certification to ensure safety compliance standards. That led to the birth of LestaUSA, a product of DeGeest Automation, which, along with DeGeest Steel Works, is a division of DeGeest Corporation. The company’s facility in Tea, SD, serves as home to LestaUSA, exclusive North American distributor for Lesta finishing robots. Lesta robots are manufactured, assembled, integrated and serviced by DeGeest Corporation.
LestaUSA was introduced to the finishing community at FABTECH 2019 in Chicago. DeGeest Automation continues to develop more applications for Lesta technology, like the debut of the Suction Blow Off self-learning application at FABTECH 2019. The experience gained in certifying Class 1 Div I equipment for North American standards, as well as international connections, promises a future of bringing more European finishing technology to North America.
Following FABTECH, the Official Equipment System Partner program was established where LestaUSA has collaborative agreements with major powder and liquid equipment brands in North America – Nordson Corporation, WAGNER Industrial Solutions, SAMES KREMLIN, Graco and Durr to name a few. The national automation and sales teams at these brands have selected equipment to integrate with Lesta robots that will be most beneficial for their customers and are now featured in the LestaUSA Integration Center and Test Lab for their customers to try firsthand. Whether manufacturers are building a new system, or adding to existing batch booths or conveyor systems, Lesta can successfully integrate into any type of finishing system. And, with the involvement of the Official Equipment System Partner participants, most of this can be achieved with the manufacturer’s current equipment suppliers and their local service technicians.
Integration Center & Test Lab Brings It All Together
One of the biggest challenges in the finishing industry is navigating all the moving parts so a finishing solution comes together seamlessly, thereby eliminating any apprehension. The LestaUSA Integration Center & Test Lab, which is also located on the DeGeest Corporation campus, is where hand built Lesta robots go to be integrated and tested.
The Integration Center is where manufacturers interested in adding robotics into their operation can test equipment supplied from LestaUSA’s Official Equipment System Partners, such as particular mix systems, spray gun technology, and powder formulations with Lesta robots.
From there, the manufacturer’s robot will enter the LestaUSA Test Lab, where run-off is performed to ensure the system will work as intended on day one following installation. The Test Lab also gives companies an opportunity to be trained on how to operate the system and work out any obstacles to make sure everything is tailored to their operation.
“Our Integration Center and Test Lab are proof that we want to work together to provide an easy-to-use robotic solution,” said DeGeest. “This solution ultimately came from the challenges we faced at DeGeest Steel Works. We know firsthand what this system will do, and now we’re in a position to share this knowledge with the North American powder coating market. So far, the response has been extremely positive. We have already hosted visits for customers of our Equipment System Partners from all over North America to see their equipment work with a Lesta robot. We’re able to teach them how to adapt their current system or how to design a new one. Customers appreciate being able to touch this technology and experience it for themselves.”
What started as a challenge has, indeed, turned into an opportunity. Not just for DeGeest Steel Works, but for the entire powder coating industry.
Brad Ruppert is manufacturing and paint line engineer for DeGeest Steel Works, Co. and application specialist for LestaUSA.