Tightening up boring machine accuracy.

Long a vital piece of a facility's woodworking equipment, boring machines are being manufactured with higher accuracy and increased production capabilities.

Since the mid-1980s, virtually every high production piece of woodworking equipment on the market has been available with some kind of computer control. Ten years later, machinery manufacturers are continuing to work toward making CNC equipment more flexible and user friendly.

In the case of boring and drilling equipment, representatives of companies that manufacture or supply machinery told WOOD & WOOD PRODUCTS that improved precision is meeting end user demands for more demanding tolerances. "Machining accuracy is really a function of overall machinery accuracy," said Jim Eckberg, advertising manager with Komo Machine Inc. "Machine accuracy is solely the result of a proper technology choice by the builder. The combination of the positioning motors, guideway systems and computer control resolution should result in a machine capable of positioning and repositioning plus or minus a fraction of a human hair every time."

However, operators should remember that no matter how accurate a machine is, the wood being machined can have an effect on the final tolerance.

"The tolerance of manufacturing parts to within 0.02mm is pretty much the industry standard," said Norman Kaweck, director of engineering with Biesse America. "But meeting these tolerances is compounded because wood is wood and the nature of the material causes it to be dimensionally unstable. Swelling and shrinking of the material happens with solid wood, particleboard and MDF."

Operating boring equipment with digital controls and having the ability to obtain the correct location after pattern changes are allowing for increased productivity. At the same time, prices of advanced boring equipment are becoming even more affordable, allowing wood product manufacturers to become more efficient, accurate and profitable.

Why digital?

Quite simply, digital technology is a more precise form of measurement and its use can be applied to multiple spindle and point-to-point boring machines.

"Precision has been attained through the development of digital technology," said Bruce Clavenger, regional sales manager with Koch Ltd. Machinery + Systems. "This is similar to the difference between analog and digital watches. For example, if you have an appointment at 11:00, looking at an analog watch with hands will tell you about what time it is, but to get the exact time requires looking closely at the minutes and seconds. That is irrelevant until you meet a customer who says you must arrive within 30 seconds before or after the allotted appointment time or your product won't be considered. For sure then you'll want a digital watch so you can arrive at precisely the correct moment.

"The same applies with precision boring operations, only in this case instead of your product not being considered because you're early or late, it'll be returned because the parts won't fit together properly. Electronic digital readouts are a step above mechanical," Clavenger said.

Consistency every time

Depending on the product manufactured, boring and drilling equipment often has to go through several pattern changes daily. An extended product line can cause a demand for CNC boring equipment because of its benefits.

"More of the larger RTA manufacturers are looking at specialized production runs and JIT manufacturing to meet that need," said Robert Howell, Morbidelli sales engineer with Tekna. "CNC boring equipment appeals to them because it helps them reduce the set-up times required for quick changeovers. A custom manufactured piece of furniture means more to a customer today, and there is a finer line than ever between standard and custom furniture."

The ability to maintain the memory of the exact position can be demanding on machinery, especially if part tolerances are very exacting, such as when a 32mm boring system is being utilized.

"The stability of the machine is the most important factor here," said Hans Mason, Jonsdorf product manager with Altendorf America, div. of Stiles Machinery Inc. "As the location of the referencing stops are absolutely crucial to repetitive accuracy. Pattern changes occur very frequently on most CNC boring/drilling machines on a daily basis. That is one of the reasons that they have a lot of appeal to the woodworking business. As long as your reference points are intact, your parts will be consistently accurate."

Multiple spindles utilize same spot

To make sure parts stay square and accurate when using multiple spindle boring machines, some manufacturers suggest that end users keep one station in the same position as a reference point for the other drilling stations.

"Machinery manufacturers are teaching the process of using a single panel starting point," said Ase Stornetta, president of Ritter Manufacturing Inc. "This makes all the hole locations predictable. Machinery designed with a single reference point is also useful in achieving a high degree of predictable hole locations, reducing machine set-up time and boring pattern complexity."

Another way to boost productivity with a multiple-spindle boring machine is to add additional stations to the machine.

"One area of concern we have understood from customers is part placement, meaning how can they make sure the parts are always square and accurate when in the machine," said Jeff Oliverson, national marketing director with Mountain View Machinery. "One development we have come up with is to try and get the customers to get enough insertion stations so they do not have to reposition drills or insertion stations from set-up to set-up. This guarantees better accuracy, little or no changeover time, and no worrying or checking to make sure whoever changed the pattern did it correctly."

Capability up, price down

For repetitive drilling operations with little or no pattern changes, manually operated boring machines have been the choice of many end-users. But with the change in production leaning toward just-in-time manufacturing and numerous pattern production, CNC boring operations are becoming more attractive to end users, especially with CNC machinery prices rivaling manual boring machines.

"I believe that other manufacturers will, in the future, offer machines which are able to compete with manually operated drills in the same price range," said Richard Hannigan, national sales manager with Holz-Her U.S. Inc. "This flexibility, along with the ability to program for common drill patterns, as well as improved accuracy and repeatability, I feel will be the future of for small-to medium-size shops. Entry level CNC machines will be easy to program and will hold appeal for even those who have no computer or programming background."

Others agree that CNC boring machines are not exclusively for large-scale production manufacturers anymore.

"Though not new on the market, the market is becoming increasingly interested in CNC machines priced under $100,000," said Tim Rose, sales and product manager of SCMI. These smaller machines give the five-man shop the power to compete with a 20-man shop at lower cost. Mid-priced point-to-point machines bring flexibility to the small shop in a manner that was only available to large shops in the past."

Here, now and hot

Although boring holes will likely remain round, how to make them in the future will still change. Areas that machinery suppliers are targeting for increasing productivity are a boring machine's ability to communicate with other machines and the ability to further reduce set-up times.

The ability for one machine's computer to be linked to another via a telephone modem is being adopted in many facilities. Software programs created for these machines help them communicate between each other.

"It is much easier to use programming software that can be linked to other machines in the shop and allows users to program and control multiple machines from a single software package," said Greg Hammersley, Weeke product manager with Stiles Machinery Inc. "Bar code scanning is the most accurate method of program retrieval, as it eliminates most of the potential for operator error in identifying the correct and most current program. After the correct program is called up, CNC machines run the programs and parts are machined to within a few thousandth of an inch."

Tooling changovers are arguably one of the biggest time thieves when it comes to boring machine productivity. In addition to setting machine parameters when changing a boring pattern, replacing the necessary boring bits also requires attention.

"New developments in boring and drilling technology include more flexible tooling changeover capability for businesses requiring a larger variety of drilling needs," said Mason. "Automatic tool changes, for example, save time for the operator. Other developments include more use of higher levels of sophistication in the componentry of the machine, which leads to even more (can you believe it?) accuracy or consistency over the long and short term."

One of the greatest concerns of machinery manufacturers is even though they are building high-tech machines capable of greater productivity, are end users able to grasp the training associated with maintenance and operation? The answer is "yes," through user friendliness.

"New customer training and advanced training for machinery is helping users become more productive," said Jack Ragan, sales engineer with Delmac Machinery Group. "For example, using Winner90 software has been found to be very user friendly."

One area manufacturers are focusing on for user friendliness is on the monitors.

"Visual displays with CNC set-ups are designed to help minimize human error," said Rick Bullin, sales vice president with IMA-European Woodworking Machinery. "New and better displays for CNC setups are being offered."

Conclusion

A combination of digital technology, precision, and reduction in the price of the technology associated with today's boring technology are all allowing end users to experience the benefits of highly accurate and productive equipment without breaking the bank. In addition, purchasers of new equipment will also be able to maintain a strong business relationship with their customers by offering them better machined products.

Available equipment

The following is a review of some boring equipment available to the woodworking industry. For more information, circle the corresponding numbers on the Reader's Service Card. For a more comprehensive overview of the boring equipment market, consult the 1996 Red Book Annual Buyer's Specification Guide.

The Speedy 207 CNC drill from Holz-Her US Inc. can perform standard drilling operations as well as the use of RTA fittings and dowels. The machines are reported to be easy to program and will hold appeal for even those who have no computer or programming background.

The Vitap Sigma 2TA automatic boring machine from Atlantic Machinery Corp. is a compact feedthrough drill with two opposing horizontal boring groups with 21 spindles each. The configuration also includes multiple swivelling vertical boring groups with either 21 spindles each or with split head configurations. Additional features include alternate horizontal/vertical drilling circuit belt conveyors fitted on pneumatic cylinders plus front and side pneumatic pushers to align the panels. The machine offers all boring group adjustments by digital readout with pneumatic locking.

The Weeke BP 12 CNC point-to-point machining center from Stiles Machinery Inc. features four selectable horizontal spindles, 18 selectable vertical spindles, a vertical 7.5-hp router with automatic tool changer and X/Y programmable grooving saw. The center is now equipped with a Windows-based control software and comes with bar code software installed. The programs are reported to be compatible with leading software packages including Holzma Cut-Rite Plus, Pattern Systems Drill Mate and others.

The Jonsdorf Unidrill point-to-point machine center from Altendorf America, div. of Stiles Machinery Inc. offers quick processing for the custom shop. The machine offers dowel drilling, line boring and grooving by means of a five aggregated revolving turret-style unit. Multiple hole diameters are possible without changing the drill bit. Drill pattern software is included at no additional cost.

The Morbidelli Maxima line boring machine from Tekna is a computer-driven machine which offers reported flexibility, low set-up times and high-production cycles. A computerized system is used for positioning the upper and lower vertical boring heads. Quick release boring heads can be prefitted with proper tooling away from the machine and quickly installed to reduce tooling changeover.

The Rover 13 from Biesse America is an entry level point-to-point boring machine which features complete N.C. control of the X, Y, and Z axis, star linear guides for axes movement, mushroom clamps and centralized axes lubrication. Axis speed is 60m/minutes along with four-sided horizontal boring.

The Tech 90 Super point-to-point boring machine from SCMI is designed for the custom cabinet shop that needs flexibility as well as high-volume capabilities. All functions are menu-driven, and the boring head is comprised of nine vertical spindles, two opposed spindles for horizontal boring, a grooving saw and a 4.5-hp CNC router. The machine is equipped with vacuum hold-downs and is capable of running mirror imaged parts on the right and left sides of the worktable.

Equipped with two 75-spindle drill rows, the Ritter R-150 Panel Master line drill from Ritter Mfg. Inc. can line drill 150 holes in a 96-in. panel in 10 seconds. The R-150 is all electronic in its operation. With the use of PLC controller and a precision ball screw table feed systems, the machine can perform through-drilling functions with clean results on both sides of the panel. Panels of 48 in. or less can be run in pairs.

Delmac Machinery Group offers the Busellato Optima CNC machining center. Engineered for architectural millwork shops and custom kitchen cabinet companies, the machine features a working area of 900mm x 2,800mm x 60mm. Featuring 14-vertical and 8-horizontal spindles, it can be equipped with up to four additional units including a horizontal router, automatic saw and sanding unit.

The Accu-Systems Model H-23 boring machine from Mountain View Marketing features a 23-spindle head on 32mm centers, 8 to 14 insertion stations, microprocessor-controlled, full length fences, automatic mirror imaging for left and right hand parts, and twin-feed bowls.

The Model BL-G universal boring machine from Koch Machinery & Systems has been designed for boring applications in rail and panel manufacturing and for backpost-boring in the chair and upholstery industry. The machine can perform vertical boring from the top and bottom and end/edge boring horizontally. All boring units can be equipped with swivel capacity. Digital and/or LED readouts reduce set-up time. Optional features include a trim saw, hopper feeder and computer set-up.

The V. Alberti machining center from Servatek Inc. features a mobile work area with its twin-table movement in the Y axis under full electronic control. Because of its four axis, twin-table design, a tandem cycle creates lower overall machining cycle times while operating at realistic feed speeds. The centers feature 18 to 27 vertical drills, tool changers with electric spindles, horizontal drilling, programmable sawing units, and other options.

The Nottmeyer SP/N-1 and SP/N-2 CNC equipment from IMA-European Woodworking Machinery offer Windows-based user-friendly computer command screens. Available with quick change drill chucks with pre-fitted bit holders, the machine can handle virtually any workpiece from less than 1/2 in. to over 1 1/2 in. thickness and up to 120 in. long and over 39 in. wide. Throughfeed speed can go as high as 250 feet per minute and a reported 30 panels per minute.

The LB-30 Locomotive line boring machine from Castle Inc. features the ability to drill 30 holes on 32mm centers and has no gear box to create friction between the gears. According to the company, the machine requires little maintenance and parts are inexpensive to replace.

The Pade Uni 5 CNC machining center from Macoser Woodworking Machinery has a 2,500mm x 500mm machine table which can be used as a single station for long pieces or as a double station, where finished pieces on one side can be removed while others are being processed on the other side. Working pieces are clamped by means of pneumatic cylinders and/or a vacuum system. Sliding guides of the X, Y, and Z axes slide on linear rails by means of preloaded roller bearings.

The Scheer/Byrnes Model DB22 in-line multiple spindle drilling machine from Richard T. Byrnes Co. Inc. is designed so that two rows of holes can be drilled in one working cycle. The unit comes standard with an extraction hood to help keep chips and dust from the workplace when connected to a central dust system. Additional features include an electric switching cabinet and pneumatic maintenance lift.

The Masterwood/Riebling Ligna MP3 modular multi-boring machine from Eric Riebling Co. features horizontal and vertical independent boring units with optical readouts and pneumatic looking. Pneumatic stops with micrometer perform exact centering of left and right hand panels. An electric control panel has stops and boring heads sequence selection. The machine is available with 0-90 degree rotating heads and split heads.

The Ayen DBE electronic drilling and insertion machine from Force Machinery Co. has been designed to drill both vertical and horizontal dowel holes with insertion in a single cycle for KD and RTA applications, drill and insert on an angle, drill and insert dowels into long parts with minimum set-up, and changeover to other dowel sizes in less than a minute. The machines bore horizontally with 21mm, 23mm, 25mm or 32mm spindles. Six glue and dowel insertion units are standard.

The double-spindle boring and assembly unit from Unique Machine & Tool Co. produces face-frame assembly systems with either a single- or double-spindle unit. The boring unit produces pilot holes and counterbores for perfect alignment of material and placement of screws. The assembly table has a 12-ft standard length with four clamping cylinders individually controlled to hold parts square and true while inserting screws.

The Type N 6 hopper feed boring unit from Henry Weigand Corp. offers six boring stations for high speed small diameter boring and step boring of 12 in. on up to 13 1/4 round or squares. The company claims the machine can produce 800 pieces per hour with each drill performing two strokes.

Miscellaneous equipment

The Model 2111 adjustable drill head from Tyler Machinery Co. Inc. is available with two spindles that have an adjustable spindle distance of 1 in. through 6.6 in. Drill spindles are designed for standard screw shank bits, thus eliminating the need for collets and assuring proper drill positioning. Maximum drill spindle speed is 4,500 rpm with a maximum 2-hp drive motor. Circle #380

The new 13 spindle boring block from Komo Machine Inc. adds point-to-point technology to VR Series CNC routers. The 13 vertical and horizontal spindles are fixed on 32mm centers and the modular design allows each spindle to be used independently. The unit is reported to be compatible with Router-CIM programming software from CIM-Tech. The combination of router and point-to-point capabilities in one machine opens up opportunities for increased flexibility and lower-cost production.

The Extended Duty tooling package from Thermwood Corp. is intended for applications which require a number of different machining operations. The core of the package is Thermwood's 10-hp extended duty router. To this can be added one or two add-on "Piggy Back" router spindles. The 10-hp main spindle can also be equipped with a five-position automatic tool changer, and a 32mm drill bank can be added to the routers to complete the tooling package.

The Kreg Pocket Boring Machine from Kreg Tool Co. features a pneumatic boring motor which is reported to eliminate the need for the operator to stop and make adjustments to the feed rate of boards with different densities. Additional features include a close tolerance bushing to guide the drill bit. The bushing is reported to provide close support against the face of the workpiece, eliminating tear-out even when boring cross-grain in plywood.

The Veritas 32 cabinetmaking system from Veritas Tools Inc. is suited to short runs and custom cabinets The system is based on the 32mm system of measurement, but can also be used with standard measurements.