George Guenzler & Sons Inc. has been turning wood for almost 100 years, but is not afraid to look at things differently.

As an example, a Shoda CNC router and other CNC machines are used to bore, cut, shape and sand solid wood chair frames, stair and furniture components.

Guenzler, located in the manufacturing city of Kitchener, Ont., about 50 miles west of Toronto, dates back to 1908 as a wood turning company supplying local furniture manufacturers. Today, the company ships turned and shaped components and chair frames to customers across North America.

"Our challenge is to provide good quality in low quantities at reasonable prices," says president Norbert Englisch. "Customers' expectations for quality haven't changed, but they want to order in the lowest possible quantities while maintaining large order pricing, so we have to be able to make smaller lots efficiently."

Guenzler's sales manager, Neil Devereaux, says that reducing costs is a goal. Reducing setup, cycle time and material handling costs offsets raw materials and other costs the company can't control, and allows smaller quantities to be made more efficiently.

Normal lots are smaller

A "normal" lot may be 100 chair frames. Guenzler is seeking to produce a 75-piece lot for the same price as a 100-piece lot.

In components, 500 to 1,000 lots were the norm. Now customers are asking for 100- to 200-piece lots with shorter lead times.

The company supplies railing, chair and furniture components to stair and furniture manufacturers. Growth is coming from producing one-time orders for furniture manufacturers that specialize in supplying furniture to the hospitality industry.

Special projects for the company have ranged from intricately carved and shaped walnut table legs for a library project to the boxes and presentation cases for the 2002 Winter Olympics medals.

Chairs, stairs and components

Englisch says that about 40 percent of Guenzler's business is chair frames, 35 to 40 percent is stair railings and components and about 20 percent is custom furniture components. New growth will come from expanding further into component manufacturing, hence the purchase of new CNC equipment and upgrading existing equipment to NC capability. This has enabled the company to undertake more complicated projects, produce smaller quantities with greater accuracy and shorter lead times.

Almost all work here is solid wood (a few items such as seat frames are made of plywood). Primary species used for chair frames are cherry, hard and soft maple, walnut, red and white oak, and mahogany. For stair components, red oak, hard maple, birch and poplar are used.

General manager Barry Freiberger says that Guenzler has benefited from an increased willingness by manufacturers to outsource work they previously did in house. He says that the company has had the opportunity to do more chair legs, mouldings, table lippings and components for store fixtures.

Adding value

In addition, Freiburger says that Guenzler seeks to do work that adds value.

"We are often called during the engineering and design process and asked how to make a particular item stronger and/or less expensive," he says. "At the same time, we ask if we can do more than just manufacture the components. We look at additional parts, machining, subassembly and finish sanding as ways of assisting our customers and adding value to the work we do."

Englisch says that newer machinery and better quality tooling have contributed to a high level of efficiency and less rework. Equipment like the Shoda CNC router delivers more accurate and consistent components.

Parts are drawn in AutoCAD 2000. A three-dimensional digitizer is used to assist in drawing the parts more quickly. The three-dimensional capability is necessary for boring and varying cutting angles in the solid wood parts machined on the router. Mastercam is used to develop machine codes for the router program.

Guenzler has one moulder, a Weinig Unimat 22A, Cantek over-and-under planer, Wadkin straight-line ripsaw, Nelson & Atkinson cut-off saw and Doucet clamp carrier in the breakout department.

A Pade eight-head linear shaper does cutting, shaping and sanding of curved and straight parts. Pieces go through the shaper lengthwise. Four heads from the front and back cut, shape and sand the part on each side. The parts return to the starting point at the front of the machine and are removed and sent to boring or assembly.

The Shoda Supermax-twin has two heads and two tables. Each head can accommodate 16 different tools, including router bits, shaper heads, vertical and horizontal boring, saws and even sanding heads.

Parts are held by vacuum on the two 5 x 5 foot tables. Smaller parts are held with jigs and fixtures that are formed to the shape of the part and use a small rubber gasket to ensure adequate suction and holding power. With aggregate heads, the Shoda router can be used as a four-axis machine for vertical and horizontal boring, cutting, shaping and sanding. To use the Shoda efficiently, at least four different operations need to be performed.

Specialized equipment

Devereaux says that Guenzler has plenty of shapers, routers, saws and drill presses that can do specialized tasks quickly if the order is too small to justify setting up the Shoda. On the other hand, a large run with only one or two machining operations is also more efficiently done on dedicated machines.

Guenzler also has a Reichenbacher multiple-spindle copy carver for making cabriole or Queen Anne legs as well as roll-shaped chair parts. Guenzler craftsmen also do single-spindle carving, one piece at a time.

A Pade CNC double cutoff and boring machine is another recent addition that was purchased for accuracy and repeatability. A Sandingmaster widebelt sander and three other edge sanders, a stroke sander, drum sander, profile sander and five sanding/polishing pedestal sanders are located throughout the plant.

Seven Mattison lathes, one Centauro CNC copy lathe and three Nash rotary sanders are used to make stair components and turned legs. Guenzler added numerical control capability, an expensive upgrade, to reduce operator errors and improve production times. Aluminum hydro-lock cutterheads from from Western Cutterheads have also been purchased.

Chair frames are assembled at several stations. Pneumatic clamping is planned to reduce assembly set-up time. Assembled chairs are put on a new conveyor that was added to the plant in December and is intended to improve flow. Finish sanding is done at seven individual stations. 

Big delivery advantage

Reduced lot quantities and faster delivery times are seen as an advantage by Guenzler over imported component suppliers.

Guenzler renovated the 55,000- square-foot building, formerly used by a metal fabricator, when the company and its 65 employees moved here three years ago.

A major feature of the renovated building is the modular DISA MSK 2000 chain filter dust collection system that was designed and installed by Waltco Systems, Ltd.

In the plant, five separate dust collectors feed a single large hopper. Conveyors move dust and chips to a truck trailer. Freiburger says the
advantage of a modular system is flexibility.

When only part of the plant is running, that area's dust collection is turned on. Future expansion is handled by adding sections to the conveyor.

Before the move and since, a consultant was hired to review production processes with the specific goal of reducing waste. Factory layout, material handling issues and suggested changes to methods and workstations were part of an ongoing process to create a leaner operation.