As a result of the cost and importance of a shop's machinery, many fabricators spend time researching equipment before deciding on a major purchase. A machine's stability and reliability may be evaluated, its reputation determined, and research may even be conducted via the Internet by some fabricators prior to buying.
Personnel is also an issue, as finding employees with the skills and experience to work with such machinery is not always as easy as placing a classified advertisement. Fabricating companies have put a focus on training, making sure employees are comfortable with their work.
This roundtable discussion includes the following participants from varied stoneworking operations in North America:
SW:Explain the size of your firm and the type of work you do.
Adams: I have several firms that employ a total of 92 employees. We do upright memorials, cemetery features, mausoleums, kitchen countertops, and granite foundations.
Dusenberry: We are 15 people now, and we're basically focused on sculpture and high-end architectural detail. We also work on restorations such as the Tweed Courthouse in Manhattan, which was originally built by Mayor Tweed and is now being restored by the State of New York for $100 million. We're doing the carved elements for that; it's all in Georgia marble. We're redoing and redeveloping models from the degraded original pieces and recarving them in large quantities. We also do a lot of specialized work that requires advanced digital acquisition capacities. While we work with some of the most advanced technology in the field, all of our employees are trained in the traditional methods of stone carving.
Mattke: Cold Spring Granite Co. employs 1,400 people, has 24 individual manufacturing facilities at five locations throughout North America, and has annual sales of approximately $150 million. We quarry nearly 30 granites of our own, and our commercial division fabricates primarily for larger building projects or resale to smaller fabricators for residential and small commercial use.
Tibett: Union Granite & Marble is a manufacturer and installer of various types of customized stone slabs used in high-end residential homes. The company employs 23 people and has a facility of approximately 20,000 square feet.
SW:What kind of equipment do you have in your shop?
Adams: We have a tremendous amount of machinery - some imported and some we build locally with machine shops. We have automatic diamond saws from Wilson Industrial Electric, polishing mills from Hensel and Wilson, guillotines from Park Industries, titling bridge saws from Wilson, an automatic sandblasting machine from Pedro Benavides GmbH, an SFT contour diamond wire saw and much more.
Dusenberry: We have a two-axis diamond robot wire saw manufactured by Pellegrini. This computer-controlled saw has an extra long bed to handle pieces up to 20 feet long. We also have an Omag CNC milling machine with laser digitizing capabilities. It has the capacity to handle 10- x 5-foot blocks. This machine can cut stone to within 0.1 mm and it doesn't just cut geometric shapes; it can carve organic forms as detailed as the human head. Two new machines will be arriving within a few months - the Omag three-axis CNC milling machine and the Omag Mill98 five-axis CNC milling machine with laser digitizing capabilities. The Mill98 is a bridge milling machine in which the object remains still and the mill moves around it. We also have a Loeffler bridge saw and a Carlson 6-inch radial arm drill. Ours is probably one of the most advanced shops in the nation. We are continually expanding our digital acquisition capacity. We use several different laser scanners built by ScanTech, including a dedicated CNC scanning machine, the ST600. Our laser scanner takes measured points of the model surface every 0.5 mm. It repeats this process around the whole object, producing a virtual model that can be manipulated, enlarged or decreased before it is milled.
Mattke: We have equipment from many major manufacturers throughout the world, and we also have equipment that we have manufactured in Cold Spring for our own use. Additionally, we have our own diamond department that makes many of our own blades and bits and markets them under the name DiamondWright. Our equipment includes shot saws, wire saws, polishing lines, thermal lines, CAT saws, bridge saws, profiling equipment, anchoring and edge finishing equipment, etc. We also have a bronze foundry and all of the equipment that goes along with that type of an operation.
Tibett: Our shop is set up with a variety of fabricating equipment. We have three bridge saws: a GMM Tecna 35 that was purchased last year, a Gregori Sombar purchased in 1990, and a Terzago F30 purchased in 1989. We also have a Wesely UF150 router machine that was purchased in 1990, two Zattoni radial arm polishers purchased in 1990 and 1999, and a Schubert air pollution machine also purchased in 1999.
SW:How do you evaluate new equipment when you are considering a purchase?
Adams: I evaluate the stability of the equipment and its reputation in the industry. I consider how well the equipment is built as far as tool wear goes. I go to Italy and to [the Nuremberg Fair] in Germany every other year, so I have gotten to know the manufacturers, and if I see something at a trade fair that I am interested in, I go to the factory to see the equipment in operation before making a purchase.
Dusenberry: I look for the flexibility of the equipment, its reliability and its ability to change its function. Then, of course, there's cost. Because we're not a production firm and we're so deep into CAD/CAM production, I look at what software the equipment interfaces with to find if it can be integrated into what we're already using.
Mattke: We measure its efficiency, dependability, maintenance and applicability for our intended purpose. We also evaluate whether or not the equipment will support our lean manufacturing principles of flexibility, portability and one-piece-flow.
Tibett: In addition to viewing the latest technological fabricating equipment, new equipment is evaluated by calling companies that are currently using the equipment in question. Union Marble also does its own evaluation of equipment based on the pros and cons that were found by its own research via the Internet, trade journals, and the opinions of other skilled workers within the industry.
SW:What piece of recently purchased machinery - within the past few years - has made a significant impact on your shop, and why?
Adams: As far as countertop operations go, I would say the Thibaut T55 edge machine because it speeds up the production of specialty edges. For our monument operations, the SFT contour diamond wire saw has made a tremendous difference in the types and shapes of monuments we can manufacture.
Dusenberry: The machinery we're receiving in February - the Mill98 five-axis machine - is the most advanced machine out there produced by Omag. We anticipate that it will make a significant impact due to the flexibility of its milling head and its ability to move around a stationary block. This will allow us a greater range of milling possibilities that were previously not available.
Mattke: Shot saws and polishing line, Vantage line for treating slabs. All of these have helped us improve our efficiency and increase capacity.
Tibett: The Rosh Industrial material handling equipment, which works similar to a vacuum, transports the stone slabs via suction. This piece of equipment has proven to be our biggest asset. This piece, together with the overhead crane purchased this year, made it possible for one person to be able to move slabs through the shop in a much safer and timely manner.
SW:How do you go about hiring, training and keeping employees for stone working?
Adams: Because we are located in Elberton, GA, we are generally able to hire employees with experience in working with granite. If not, we train them ourselves.
Dusenberry: We have a hard time. We're looking for people all the time. Ours is a shop that requires a high level of skill, and we're looking mainly for carvers, not production workers. Those folks are rare birds. We've brought folks in from Europe and Japan and from elsewhere abroad, but we're always looking for qualified staff. We have someone coming in from Italy soon, but it takes a year or so to bring foreigners in through legal channels.
Mattke: We are an ISO 9001-certified company. We invest many thousands of hours in training each year and have developed specific work instructions for all operations within the company. This process helps us with both new hires and in developing ways of improving our operations. We regularly survey our market to make sure our wages and benefits are competitive and have programs in place that allow employees to share in the company's success.
Tibett: Hiring is done through the networking of in-house employees as well as through people within the stone industry. When a new employee is hired, his or her performance is evaluated. Upon evaluation, each employee is enrolled in a training program based on the skill level demonstrated. Some employees start at entry level and are positioned to work alongside a skilled veteran employee, creating an apprentice-type relationship. Other more skilled employees are chosen to be project managers or shop foremen. These supervisors oversee all the jobs and implement company policy set by the higher management. The employees are motivated by promotions within departments as well as throughout the company. Salary increases are based upon knowledge and the production output each employee contributes to the company.
SW:Other than personnel issues, what is your biggest challenge as a fabricator today?
Adams: Competition and pricing.
Dusenberry: Getting the right combination of work in the shop to optimize our space and the staff's time. It is difficult to get the right combination of jobs that work well together so that if something in one job is not moving, another job compensates.
Mattke: Working with the marketplace/customer to provide whatever the customer wants, whenever the customer wants it. That is our goal. It is challenging to be flexible enough to accomplish that with the lead times we traditionally associate with stone. That is why we are so focussed on lead time reduction.
Tibett: The biggest challenge as a fabricator is to meet specific deadlines within a short period of time without compromising the high quality Union Marble is known to produce. There are many factors and obstacles that are beyond a fabricator's control, such as accommodating requests of other professionals associated with the job, material limitations, requirements of architectural layouts and designers' wishes.
SW:In your shop, how much work is done by machine and how much is done by hand? What processes are still done by hand?
Adams: In our countertop division, about 70% of our work is done by machine and 30% is done by hand. Some of the polishing and shaping of edges in tight corners is still done by hand.
Dusenberry: I would say that 70% is done by machine and 30% is done by hand. All of the finishing is done by hand and, of course, most of the finish carving is also done by hand. Surface finishing is done by hand, and some particular pantographic enlargements that will not adapt to CNC technology are still done by hand. We still use some old fashioned methods of pointing - Renaissance methods like enlarging with compasses. Some work is too large for the equipment to handle, so it has to be done totally by hand.
Mattke: There are still some drawing and design, polishing, carving and etching, rock pitching and custom shaping processes that are done by hand. Handwork represents relatively little of our total process. There is more handwork done in the memorialization division than in our commercial division.
Tibett: Seventy percent of the fabricating work is done by machinery, and the balance is done by hand. The grinding, polishing, cut outs and gluing are still done by hand.
SW:If and when you import slabs, what is the quality of the surface polish? Do you have to do much additional polishing before delivery to the customer?
Adams: As far as the thin slab market goes, the quality of slabs from Italy is generally much better than those coming from South America. We occassionally touch up the finish on imported slabs.
Dusenberry: We tend not to work with slabs at all. We'll only work with slabs when they're used as peripherals in conjunction with a bigger project.
Mattke: We do import stone. In most cases, the quality of the finish on the material we import requires no additional work.
Tibett: This question does not really apply to Union Marble because we do not import slabs. However, much of the material selected today is brecciated, which requires additional fabrication such gluing, grinding and re-polishing.