Continuous Production: Moving Right Along
- Published: 17 February 2009 17 February 2009
Get used to hearing them, because these are two words that will keep popping up about stone fabrication: continuous production.
For most shops, it’s a machine-management concept that isn’t going to come into the door tomorrow, or next month, or next year, or maybe never. And yet, it’s likely to change the U.S. dimensional-stone industry and, quite possibly, the way you do business.
It’s also something that could put the squeeze on a number of shops that, by today’s standards, look to be very successful. Some owners who think that they have it made may have to make some hard – and expensive – decisions in the near future.
“I think the stone industry is ripe for it,” says Roland Pfender of Pollux Manufacturing in Minneapolis. “I think we can look at other industries and learn from those industries, apply that to what we’re doing, and get a lot more efficient.”
The idea of continuous production – a smooth automated workflow in stone fabrication – is more than just a bit of salesspeak or a machine option. It’s a system approach that’s now offered, in various forms, by Löffler Maschinenbau GmbH, CMS S.p.A., Thibaut s.a., Burkhardt GmbH and Breton S.p.A. – and other manufacturers will likely tie into the concept in short order.
“I’m sure it’s definitely a trend, mainly in America, on the processing of the kitchen business,” says Jacques Thibaut, president-director of Thibaut in Vire, France. “I’m sure that this is something that’s going to develop.”
But, what is continuous production? The technical explanation involves the integration of computerized machinery with a controlled automated workflow. The cut to the chase is that it’s the way to transform a fabrication shop into a factory.
“It goes back to what the machine-tool world went through 20 years ago,” says Neil Cigelske, a Löffler-system specialist for EuroStone Machine in Atlanta, “as it went from mom-and-pop job shops operating one machine and taking parts off one at a time, to a process where the piece is continuously being advanced into a machine automatically and the operator is loading and off-loading outside the machine.
“It’s a capital investment that has to be made at the front end, meaning the equipment. But, it’s also a rethinking of the whole process – how do you take a slab through to the end process, keeping it automated and tracked electronically through digital means – with the least number of hands touching the stone.”
Or, in other words, it’s not so much in making CNC machines work as it’s assigning the work.
“This is not a CAD-CAM package,” says Saba Vasanthan, product manager for CMS North America Inc. in Caledonia, Mich. “This is mainly for administration of the shop, front- and back-end.”
HOW IT WORKS
To clarify this, let’s take a look at the CMS system, which the company calls Continuous Production Modules (CPMs). (Versions from other companies differ in software and other details, but the process is basically the same.) A slab is brought to the beginning of the production line, where it’s digitally photographed. The image is used to electronically locate where individual pieces of a job will be cut from the stone, and also mark out any bad spots to be avoided.
From there, the stone is cut in a CNC saw, and then advanced by conveyor to the next machine needed, whether it’s an edge profiler/polisher or CNC production center. The CPM system can be designed to load and off-load pieces automatically, cutting as many manual tasks as possible out of moving the stone through the system.
Continuous production involves much more than machines, however. Slabs are marked with bar codes when they arrive in the stoneyard, and get additional bar codes when cut into pieces. By using hand-held scanners, shop workers can check and track parts; the system also keeps tabs on individual pieces.
Continuous production also ties in inventory control and job quotation/design, and involves installation scheduling to manage all aspects of a job.
“If someone walks in and asks for a quotation,” Vasanthan says, “you can draw out the kitchen, add the edges and the cutouts, and the process will create a code. When that quote becomes an order, you can work those drawings into DXF files; the system will tell you how much slab you’ll need, and whether you have that much of a particular slab in the inventory. And, when you have to ship, it will tell you whether you have all the pieces done or not.”
By fully computerizing the fabrication process, continuous production has the ability to speed up a shop’s output. That acceleration, however, can lead to a very fast mess, especially if one machine operates at 100 lineal feet per hour, and another one in the production line hits a top speed of 10 lineal feet per hour.
“I came from a fabrication background with a big shop,” says EuroStone’s Cigelske, “and we had nice machines, but we didn’t have the software. The biggest potential for problems was when you didn’t track the jobs properly. Because we didn’t have a system, it forced us to keep jobs together and made our shop inefficient. Somebody had to go into the shop several times a day update the status of every job.”
Continuous-production software accounts for this by integrating all the different machine outputs and sending some pieces to “buffer stations” to literally wait their turn. The idea is to smooth out the workflow, causing less confusion in the shop. And, because it can track all the pieces all the time, it can literally mix together parts from any job going through the shop to go through different machines, and then assemble all of them into the correct combination at the end for finishing and installation.
“It’s managing the constraints of each machine,” Cigelske adds, “so each process has the same amount of flow going through each station.”
“I have a fabrication shop here as a machine manufacturer,” says Thibaut. “We look at the flow; we put bar codes on parts and follow them.
“For a stone shop, when you reach a certain level of pieces per day – say a kitchen can have 20 difference pieces, and you have a company working on 20 different kitchens in a day, you’re going to have 20 times 20. A lot of pieces may look the same but they’re not the same; and, especially with engineered stone, they all may have the same color, so it’s very easy to make a mistake.”
The end result, if all goes well, is that continuous production increases the amount of work going through a shop and cuts the amount of work hours needed. One figure that’s being cited involves the “rule of eight:” A crew of eight can produce eight kitchens in one eight-hour shift.
“Say it takes 23 people now to produce the same output as you could do with eight or nine,” says EuroStone’s Cigelske. “If you look at the dollar savings on one shift operation alone, at $10 an hour per operator – and everybody’s being paid more now – but at that $10 rate that’s still a savings of approximately $450,000 when you figure up all the costs involved.”
Given the price tag on continuous production, however, shop owners are going to need those kinds of savings.
For a U.S. installation, for example, Löffler’s base package will likely run at $750,000, which includes automated conveyor systems between machine workstations. Thibaut’s system, using manual conveyors where workers push the pieces between machines, will be in the $500,000-$600,000 arena.
CMS pricing takes a slightly different approach by figuring the amount of work a system will produce in an eight-hour shift. Vasanthan says that prices are going to vary with what an individual shop owner wants; a system producing 250 ft² per shift could be $700,000. Something producing 450 ft² could range up to $1.48 million, which would entail four CNC production centers and a fully automatic bridge saw.
All of the continuous-production manufacturers can tailor a system to specific shop needs. For instance, Vasanthan says, if a customer does mainly 3cm with full bullnose and simpler requirements, the lineup might include the saw, three production centers and an edging machine.
MAKING IT WORK
Continuous production is a concept that’s literally cutting-edge for U.S. stone fabrication. The first systems for CMS and Burkhardt (through its U.S. representative, High Tech Stone in Elberton, Ga.) are set to be installed this spring.
The current veteran in the process is Pollux’s Pfender, who installed a Löffler system and got it into production in February 2004. The operation started by mainly fabricating DuPont Zodiaq® quartz surfaces, although Pfender says the mix is now split between Zodiaq and stone.
And, while the Pollux operation is now a model of continuous-production efficiency, it didn’t start out that way.
“Initially, we had all the machinery up and doing some trial runs,” he says. “We ran a lot of product, the saw would cut the material – and it could bury the rest of our system. We could cram a lot of stuff through here, but it was rather chaotic, and we knew there had to be a better way to do this.”
To get a better handle on the situation, Pollux brought in the South Carolina Manufacturing Extension Partnership (SCEMP), a non-profit advisory group based in Columbia, S.C. After some study, the problem turned out not to be the continuous-production process; instead, it was how the company used it.
Pfender says the advisors began working with the company on how they could use the process better. The company adapted a new strategy of synchronous flow and also studied machine-tool time and other data – items that continuous production records automatically – and began to make changes.
For one thing, Pfender notes, the traffic tie-up at the CNC machines didn’t occur because of time wasted by tool changing; it was the action of changing material on the production tables. Instead of one operator running two tables, a helper came in to aid in loading, which sped up production.
Pollux also found that some operators could be better used performing other jobs when they weren’t needed at their particular machines. It took some worker adjustment, but it made a difference.
“One of our saw operators was out there going, ‘Hell, no, I’m going to keep cutting,’ and we said, ‘No, you have to keep your eye on the buffer,’ and there’s a whole list of jobs you can be doing in the meantime,” Pfender says. “He’s a believer now, because he sees it working.
“We used to have two saw operators for each shift – one to do the nesting of the slabs, and one to do the cutting and off-loading. We now have one operator that can do both, because they can easily keep up and continue to feed the buffers without any problems whatsoever.”
The Pollux operation is efficient enough to take on outside work and still have room for more, Pfender notes. The company currently runs a two-shift operation and runs at 60-percent capacity.
At the countertop-fabrication facility for Leonard’s Carpet Service in Perris, Calif., continuous production sounds like the answer for keeping the shop running smoothly – but it’s also a place waiting for the right answer.
The 31,000 ft² shop, servicing the company’s nine design centers throughout Southern California, is trying to find direction in the midst of success, according to Leonard’s Jonathon Segaar.
“We never planned to grow as much as we have in the past two years,” Segaar says. “It’s more of a planning by the seat of your pants. When we first started, it was to figure your needs and multiply by two, and now it’s your best guess as to where we’re going to be when we finally bring in a piece of equipment.”
Working mainly with AGM U.S.A. in Pineville, N.C., Leonard’s equipment setup includes two bridge saws, an NC saw, two Intermac CNC production centers, a Comandulli edger and a Marmo Meccanica flat polisher. The company figures a 10-day turnaround on orders, Segaar says, with job fabrication finished by the seventh day; right now, scheduling is done on a Microsoft Excel® spreadsheet, with pieces moving between machines via carts.
“We come across bottlenecks on a pretty regular basis,” Segaar says. “It just depends on the kind of material you’re running and the edge detail. Right now, it’s applying wet polish, along with the quality-control checks on jobs.”
The CNC production center caused the main problems at first with heavy production, he adds.
“It took people a while to understand that you’ve got to keep moving to get ahead. You can’t just run one piece, get it off the machine, and then start thinking about your next piece; you have to have Job #2, Job #3 and Job #4 ready to go so it’s boom, boom, boom, and you’re moving from one to the next.”
One way of keeping track of everything, he says, was the stick templates for jobs, but the company recently bought its third Laser Products Industries Inc. templater; “with the new system, we need to be digital, and have to step up the software to keep the production going.”
Segaar says he’s looked at continuous production, especially with a conveyor system for moving the jobs. However, he’s not sure that what he’s seen addresses 2cm material; Leonard’s market right now splits about 50-50 between 2cm and 3cm, and the 2cm often includes a 4cm edge.
“I think it could help,” he says, “but it might not be the ultimate answer. It seems that a lot of the companies have a good handle on the fabrication process as far as tracking jobs, but in tracking templating and installations and trying to tie all that in, it gets complicated.”
Segaar’s solution may already be in the systems now available, but the question of whether continuous production is right for other fabricators is something that will be answered on a shop-by-shop basis. A large number of today’s successful shops, though, may need to start thinking about the process – and the continued success of stone may force the issue.
For large-scale shops, going with continuous production may be a no-brainer. For the medium-sized shops out there – ones defined by EuroStone’s Cigelske as doing at least five kitchens a day – the decision could be one of survival.
“Our philosophy is that you’re going to have the small mom-and-pop shops who do a lot of hand work,” Cigelske says. “They might buy one CNC, and they’re going to be a small share of the market. Right now, you have quite a few medium-sized companies; and then you have bigger companies that will continue to grow and start capturing more of the market because they can process at a lower cost per-square-foot.
“Eventually, the medium-sized guys are going to have to make a choice. They modernize and step up to the plate, or they become a smaller player because the market is going to dictate that.”
With continuous production, he adds, a medium shop can add the basic module of a CNC saw – “that’s the heart of the system” – an edge polisher and a CNC production center, along with the software, and increase to eight or nine kitchens a shift. Add a second shift, and the daily kitchen count could jump to 20.
“The medium shop can get into manufacturing, not just fabrication,” he says. “Fabrication, to me, means a lot of hand work and maybe a couple of machines; product work means the least amount of bodies touching the stone.”
In any case, market pressures may call for expanding the shop to keep growing ... and continuous production offers more than just more CNC devices on the shop floor.
“The medium shops need some solution to simplify their production,” Thibaut says, “and it’s not only putting in a machine, but also thinking of your flow.”
This article first appeared in the March 2006 print edition of Stone Business. ©2006 Western Business Media Inc.