This technical information has been contributed by
Compucraft Fabricators Inc.

Tubular Welding, Rotary-axis Laser Cutting Are Key Capabilities of Metalworking Firm

When an OEM was consistently getting poor-quality weldments for a robotic placement system, the company knew that it was time to start looking for another supplier. The OEM was having trouble with fit and function for a large enclosure that housed the main arm. As a result, it was constantly sending parts back to the manufacturer for rework.

Later, after a different job shop revised the processes and procedures for the parts, the client began to see quality on a repeatable basis. "After they came to us, we designed a fixture that would make the welding more precise," said Craig Carey, sales manager at Compucraft Fabricators Inc., located in Montgomeryville, Pennsylvania, just north of Philadelphia. "We made some changes in the way the parts were formed, and used our precision laser cutter to cut several of the shapes."

"When they come to us now, they know that the parts will be produced right the first time, which saves them a lot of time during final assembly," Carey continued. "We've probably saved them days and even weeks getting their product to market with our high level of repeatability."

Compucraft Fabricators combines sheet metal fabrication with machining and welding processes to create a one-stop-shop that cranks out high and low volumes of close-tolerance parts. The company specializes in close-tolerance sheet metal and tubular weldments, in small and large sizes and in a variety of shapes and configurations.

Also unique is its ability to punch out thin materials, both metals and plastics, including G-10, Teflon, Nylon, and ABS. The firm's punch presses often stamp out materials as thin as 0.001-inch in thickness.

"We like the challenge of making parts that are difficult to make, those with close tolerances," Craig Carey insists. "Where other companies often won't attempt certain parts, something with complex features, we'll find a way to produce it. And we try to do everything in-house. What makes us unique is the diversity of work that we do, and the fact that we have a very knowledgeable staff with many years of experience doing this type of work. Most of our key staff members, several with engineering capabilities, have been in the business 15 to 20 years each."

The medium-sized contract manufacturer offers welding and rotary-axis laser cutting, as well as short and long runs on punching, bending, and small blanked parts. Included is short-run machining for a variety of enclosures, brackets, support frames, and face plates. In-house, the company has tooling and fixturing capabilities, including DIESET design and fabrication. Compucraft takes pride in holding tight tolerances: the firm can hold ± 0.005-inch for laser cutting, ±0.001-inch for machining, and ±0.001-inch for brake forming. On a 24- x 18-inch weldment, it can hold ±0.001-inch.

Much of the work performed by Compucraft is for several large OEMs. The company regularly produces process equipment for Northrop Grumman, electronic enclosure parts for Lockheed Martin, and a multitude of aerospace and defense parts for BAE Systems, General Dynamics, and Hale Products. Its primary markets are electronic devices, medical apparatuses, pharmaceutical devices, aerospace equipment, transportation parts, and semiconductor equipment.

The company is equipped to handle both large and small parts, a bonus for OEMs. It produces, for a semiconductor equipment business, a massive frame enclosure that measures six feet wide, eight feet long, and six feet tall. It's also working on a tubular frame that is 20 feet long. Another gargantuan structure is a large drying cabinet that is eight feet tall, six inches deep, and six inches wide. Small parts, however, also fit into the mix. One part is small enough to hold a small fuse in a fuse box. The company also makes, for General Dynamics, a tube that is 0.030-inch in diameter.

Although Compucraft is not ISO 9000 certified, the company is compliant and supplies parts for many ISO 9000-certified companies. Quite often, clients require QC audits, and Carey says that the firm has never failed one.

"We have 25,000 square feet of plant space, and 33 full-time employees," says Carey. "The company was started in 1983 by Alfred Erpel, the company's president, with a partner. They started the business by making electronic enclosures. About four years ago, our president took over sole ownership of the company."

The shining star of this fabrication shop's equipment list is its Bystronic Bystar modular laser cutting system, a piece of equipment that has revolutionized its fabrication capabilities. It has 3000 watts of power, on a 5-ft by 10-ft table, with quick change to rotary-axis capability, and an auto sheet loading system.

"One of the things we perform that not too many companies offer is tubular laser cutting," Carey explains. "We have a rotary-axis attachment on the laser that allows us to make cuts in tubing at a faster rate than conventional machining. And we can cut any shape or contour onto a square or round or rectangular tube. By using this cutter, we can eliminate several milling processes, and in many cases do it in one-eighth (?) the time it would take to machine it."

Carey says that if the material isn't too thick, Compucraft can make pretty much any kind of laser cut. The company has used the laser cutting system to make spray heads for pharmaceutical washing systems and sterilization systems, and to cut square, stainless steel tubing pivot arms for computers. One regular job is cutting turbochargers for race cars.

The firm's equipment list is varied. Compucraft operates a wide array of metalworking equipment, including a 23-ton, 20-tool station (two auto-index) CNC turret punch press with PC-based control, and a 22-ton CNC turret punch press with 22 tool stations (two auto-index) and Fanuc CNC control. In addition, the firm has several standard presses from 65-ton to 1-ton.

For plate bending and tube bending, the company has four hydraulic press brakes, from 110-ton to 18-ton, all with Automec CNC double-axis gages. In addition, it has several standard mechanical brakes, a 1-inch-diameter tube and bar bender, and several saws and sheet metal shears.

Compucraft's machining equipment consists of two Hardinge CNC vertical machining centers; a Hardinge automatic screw machine, with a 12-foot Bar Feeder; three Bridgeport-type milling machines; one Jet milling machine; a turret lathe; a chamfering router; an engine lathe; drill presses; and a Vulcan heat treating oven with temperatures to 2000°F.

The workhorses of the plant are the company's welding equipment. Compucraft utilizes four Miller 350 Amp, AC-DC High Frequency Heli-Arc Welders with Syncrowave Adjustment; two Miller 250 Amp, AC-DC High Frequency Heli-Arc Welders; one Millermatic 250 Amp MIG Welder; one LORS 50 KVA Spot Welder with micro-processor controls; and one Millermatic 200 Amp MIG Welder. Also included are deburring machines and a multitude of sanders and grinders.

Compucraft takes the time to make sure the final product is always manufactured to specs. "We apply 100% inspection from the time the materials are received, before and after every process, and before the parts go out the door," Carey maintains. "I don't think a lot of fabrication shops can match our extensive quality control system."

The materials that the company works with most frequently are stainless steel, carbon steel, and aluminum, but the firm also works with brass, copper, Hastelloy, Inconel, and other engineered metals. Occasionally, the company will process plastics, like extremely thin nylon washers and gaskets that other companies may not want to handle.

"We work with tubing as much as sheet metal," Carey continues. "We can cut out ³/₄-inch pieces of mild steel with the laser, ³/₁₆-inch aluminum, and ¹/₂-inch-thick stainless steel."

Compucraft has a tooling department that makes all of its fixtures, mostly for weldments. "This is why we can hold close tolerances with our welding," says Carey, "because of the very precise fixtures that we build in-house."

Most grinding and polishing processes are handled in-plant, but paint coating, plating, and anodizing are sourced to the outside. One of the firm's long-range plans is to set up its own painting facility. In order to offer completed, net shape parts, the company performs assembly work onsite. It often constructs complete mechanical assemblies, such as a fan assembly with electric motors that it produces for a transportation business.

The company's two machining centers manufacture most of the parts—including locks, bezels, and enclosure hardware—that will be connected to fabrications. For example, the faceplate of an enclosure might need to be machined or a gasket area cut out of the backside of an enclosure. And beveled edges, holes, and threads always need to be machined.

Much of the innovation on the shop floor can be attributed to one person at the company. "Our owner is one of the most creative people I've ever met," says Carey. "He has come up with several different ideas over the years that we think are proprietary technology. A key one he came up with is for fixturing weldments to create high production."

Besides the owner/president of the company, several people on staff have engineering capabilities; they analyze each part that comes in-house for maximum manufacturability and cost efficiency. Quite often, they will take parts that were made many years ago and update them, creating a new revision of the part that is much more economical and practical to produce.

The Pennsylvania-based fabrication shop is proud of its problem-solving record. One part, a 2-inch x 2-inch piece of stainless steel tubing that was being used as an enclosure frame for a piece of pharmaceutical equipment, was taking too long to produce cost-effectively. The problem initially was that another company was milling the complex geometry of the part. Consequently, it was taking three times as long to produce the part.

"We were able to offer them great cost savings by using our rotary axis laser to cut their parts," Carey recalled. "We were able to cut the processing time from 15 minutes per part to about 45 seconds. Even though it was a little more costly to run the laser, it was still a major cost saving for them. We were able to save them about $40 per part, about $2,000 on the whole order, to give them an overall saving of 35%."

Another challenging part was a large stainless steel enclosure for the semiconductor equipment business. The units are so large and have such close tolerances that most sheet metal fabricators didn't want to get involved with them. Through specialized fixturing and proper weld prep, Compucraft was able to hold the exacting 1/16-inch tolerances from corner to corner. The enclosure also had to exhibit a highly-polished mirror finish.

"The solutions I just mentioned are the reason customers keep coming back to us," Carey insists. "Quality, while still being cost-effective, is very important to our customers."

For more information about Compucraft, visit www.metalwork.com.

This technical information has been contributed by
Compucraft Fabricators Inc.