Deburring/Finishing
Above: Gemtex surface conditioning discs are available in a range of coarseness.
January, 2024- Michigan manufacturer finishes stainless steel components with both wet and dry machining processes
If you ever drank a beverage at a major restaurant chain, chances are your drink encountered food service equipment manufactured by Glastender Inc. The Saginaw, Michigan-based company produces a host of stainless steel underbar products, including alcohol and soft drink refrigeration equipment, soda dispensers, beer towers and line chillers “the whole kit and caboodle,” says Mark Norris, vice president of operations. “We are a one-stop manufacturer of everything you need for a bar.”
Since then, the company has grown to employ 213 workers at its 186,000-sq.-ft. facility. It is critical that the laser cut or punched stainless steel components used to make the equipment have no burrs or sharp edges that can cut workers during the assembly process or cut customers who use the equipment, Norris says, “so the bloody mary is not made with real blood.” Previously, Glastender used two wet machines to deburr parts in two passes to finish both sides, but edge rounding was performed manually with an abrasive wheel. However, one machine that was about a decade old needed an expensive repair. “The other was kind of a lemon from the getgo. We just had so many repairs,” Norris says.”
A FAMILIAR FACE
sales calls and Norris visited Lissmac’s booth at Fabtech. As a result, Glastender eventually purchased three Lissmac machines: an SMW 536 wet deburring machine in early 2022; followed by an SBM-L 1500 dry deburring and edge rounding machine for large parts last July; and an SBM-XS 303 dry deburring and edge rounding machine for small parts.
“I think they make a very good product and have good support,” Norris says.
Glastender operators were initially hesitant to perform dry deburring because outside metalworking professionals told them that dry deburring a part that is not properly cleaned will start to impregnate the press brake and press bender dies and cause parts to have dimples and other quality issues that result from the buildup of grinding dust. “Brett assured us this would not happen with Lissmac dry machines,” Norris says.
Glastender purchased the Lissmac SBM-L 1500 dry deburring and edge rounding machine to process large parts
Lissmac reports that the dry machines process both sides of parts simultaneously to deburr and edge round interior and exterior contours, which was not possible with Glastender’s previous machines.
The SMW 5 series wet deburring machine does not have edge rounding capability, but the vast majority of parts that run through the machine are laser cut and only need one side deburred, Norris explains. The machine is also used to impart a No. 4 finish, or grain line, on a raw piece of stainless steel, which is the most popular finish for the food and beverage industry.
In addition, the machine corrects minor cosmetic flaws, he adds. “If there were little scratches on the workpiece, rather than throwing them out, we can run them through and re-grain line to remove most of the scratches.”
In addition to a punch press, Norris says Glastender has four laser-cutting machines. From those machines, the parts travel on conveyors to the finishing equipment, where a total of six operators across the two shifts' load them into the machines and then place the completed parts onto carts for transport to panel benders and press brakes before being funneled to the assembly departments.
“We’re a just-in-time manufacturer,” Norris says. “We do about 4,400 parts a day, and none of them hit a shelf.”
A before-and-after example of a part that Glastender finished in its SBM-L 1500 machine.
MATERIAL MATTERS
The stainless steel workpiece thickness ranges primarily from 22 gauge, or 0.0312-in., to 14 gauge, or 0.0781-in., with some applications for 7 gauge, or 0.1875-in., Norris adds.
Whether the finishing process is wet or dry, he notes the parts do not get hot. The dry machines have a vacuum to remove the abrasive belt material that’s ground away and the material removed from the workpiece. “It’s very comparable to a wet deburr. You’re wiping your finger across it and you’re not getting any residual.”
He adds that the dry machines have a dust collector to gather any dust and residue that’s generated while the wet machine has a paper filter that water passes through to remove contaminants before being recycled.
The edge rounding machines feature automatic tool wear compensation, so as the abrasive belt wears, the wear is compensated for and edge rounding remains consistent, Norris says. Another feature that has proven helpful for the operators is the maintenance timer, which tells them when to perform activities such as cleaning and services that are scheduled at specific hour-based intervals.
Lissmac provides a maintenance guide for its equipment, and Norris says Glastender references it to develop its daily, weekly, monthly, semiannual and annual preventive maintenance schedules. Occasionally, he adds, Glastender contacts Lissmac to help resolve an issue. “They’re great to work with.”
In connection with the machine installation process, he notes that Lissmac provides operator training. “A total of two days to get us up and running. It’s pretty straightforward. We had been deburring with other brand names in the past, so now with the edge rounding, that’s somewhat new to us, but we kind of know what to do.”
One of the activities Glastender is not doing nearly as much of is manual finishing, Norris says. “We’ve eliminated probably close to 90 percent of our manual operations to edge round.”
Manual operations will only decrease once the SBM-XS 300 is fully operational, Norris adds. Without a machine for deburring and edge rounding small parts, such a 1-in.-diameter washer, an operator had to finish those parts manually using what the company calls “a gray wheel,” which can introduce inconsistencies. “We have much better quality and consistency with the new machines.”
Glastender Inc., 800/748-0423, http://glastender.com/
Lissmac Corp., 518/326-9094, http://getthelissmacedge.com/
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