Lean Laser Cutting

November 1, 2010

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A Baxley Blowpipe operator prepares to load a 5- by 10-ft. blank onto the firm’s 4000-W laser-cutting machine.

A Baxley Blowpipe operator prepares to load a 5- by 10-ft. blank onto the firm’s 4000-W laser-cutting machine.

When I recently caught up with Eric Baxley, shop foreman and part owner of Baxley Blowpipe Co. in Dothan, AL, his company’s new laser-cutting machine was busy churning through 12-gauge Type 316L stainless-steel sheet for a food-processing-plant customer. Compared to plasma-arc cutting the stainless material, which the firm did for some 10 years, laser cutting allows the firm to move material through to its welding booths with a 50-percent improvement in throughput, says Baxley.

“There’s no grinding needed on cut edges prior to welding,” he says, “a job our operators were happy to give up. And, I’d much rather see our guys building assemblies than grinding off slag left over from the cutting process. On some of our work, we endured as much as 30 min. of grinding before we could move the parts over to welding.”

Laser cutting’s not new to the shop—it’s been relying on the process to carve stainless, carbon and galvanized steel, as well as aluminum-alloy sheet and light plate, for 10 years. But what is new is Baxley’s 4000-W laser-cutting machine (a Hyper Turbo-X 510 5-by-10-ft. model from Mazak Optonics Corp., Elgin, IL), a significant upgrade from its previous 2500-W machine. Why the move to more power?

“When I attended a Mazak open house at its new facility (in Elgin) in 2008, I went with no intention of purchasing a new machine,” says Baxley. “However, when I learned how the additional power, as well as a few additional new features on the machine, could help us, the investment seemed easy to justify.

“First, we’ve been taking on more and more heavy-gauge sheet and light plate,” explains Baxley, noting that the company still claims as its bread and butter fabrication of custom pneumatic conveying systems for processing plants—collection systems for moving materials like sawdust and peanut hulls. “The 4000-W laser can cut 1-in. mild steel, and the added power allows us to increase cutting speed without sacrificing quality—parts come off of the laser so quickly now that we don’t have to work as much overtime as we used to.”

Material Inventory Ready and Waiting

Baxley Blowpipe has been family owned and operated since 1946 and employs 27, including Eric’s father Jerome (president and majority owner) and brother David (who runs the shop and performs programming and parts nesting for the laser-cutting machine.) Eric’s mother (Dianne Baxley) and sister (Cindy) work in the front office.


Baxley typically runs through 10 or more different setups on its new laser-cutting machine daily, so the machine’s automated changeover capabilities really pay off for the company. Because it als uses the ideal setup for each application, assist-gas consumption has gone down, saving the company as much as $1000/month.

Baxley typically runs through 10 or more different setups on its new laser-cutting machine daily, so the machine’s automated changeover capabilities really pay off for the company. Because it als uses the ideal setup for each application, assist-gas consumption has gone down, saving the company as much as $1000/month.

In addition to its laser-cutting machine, Baxley’s 13,000-sq.-ft. blowpipe-manufacturing facility also stars a pair of press brakes, shears, ironworkers, a high-definition plasma-cutting machine (1.5-in. capacity, 8- by 20-ft. table), and three plate rollers. The Baxley manufacturing complex also is home to a 28,000-sq.-ft. facility for fabricating motorcycle trailers, which also houses a powder-coating line; a 7100-sq.-ft. shop for tank fabrication; and a 13,000-sq.-ft. warehouse where it stores more than $100,000 worth of raw material.

“Our vendors can’t believe we stock as much material as we do, but it works to our advantage,” says Baxley. “Other fabrication shops in the area offer laser-beam cutting, but they probably don’t have food-grade stainless-steel sheet in their racks. How long will it take for them to order and receive a supply of material, and how much will they have to pay?”

The firm built its inventory warehouse in 2006, in part to de-clutter its fabrication shops and clear aisle space for forklift traffic. “The inventory that was spread all over our shops also became difficult to manage and track,” says Baxley. “Now the warehouse shelves are clearly labeled and organized and material is easy to locate.”

More Nozzles Allows for Custom Setups

Back in the blowpipe shop, as the laser finishes its work on the 12-gauge stainless-steel sheet, an operator loads a completely different job on the second of the cutting machine’s two pallets. Since firing up its new laser-cutting machine in October 2009, the plant has processed 93,000 sq. ft. of sheet, 35,000 sq. ft. of which required laser cutting.

“On a daily basis, we might go through 10 or more different setups on the machine, whether it is for a change in material type or thickness,” says Baxley. “And here is where the new technology offered with the new machine really pays off. The machine can automatically change its torch, lens, nozzle and beam mode so it als uses the ideal setup for every application.”

Changeover of a typical laser-cutting machine can take several minutes, and as long as an hour if you’re customizing the entire setup for each material type and thickness. While Baxley did not do that with its older machine, its use of only two nozzles to cover its entire range of material type and thickness proved less than ideal.

Conversely, Baxley’s new Hyper Turbo-X 510 features an automatic nozzle changer and is equipped with six different nozzles (1.2 mm, 1.5 mm, 2.0 mm, 3.0 mm, 3.0 mm double and 2.0 mm double), as well as two lenses (5 and 7 in.). So not only is the machine cutting more quickly than before, the company spends much less time performing changeovers.

The nozzle changer represents one point in what Mazak calls its AO5 Point Setup: nozzle spatter removal, nozzle changeover, focal-point inspection and automatic lens replacement, nozzle inspection and replacement, and torch changer.

“Before, the operator als had a sheet or two waiting to be cut,” says Baxley. “Now he’s often waiting for material. The new machine has created excess machine time, which we’ve been able to leverage to improve our maintenance procedures. The operator now has more time to spend cleaning the nozzles, lenses, etc., which has improved our cut quality in some instances.”

Baxley notes that the goal is to clean the lenses after every 40 hr. of cutting time at a minimum for processing carbon steel, and after every 20 to 25 hr. of cutting time when processing stainless steel or aluminum.

Gas Savings Galore

Lastly, Baxley points out that he’s noticed a substantial reduction in cutting-gas consumption since installing the new cutting machine and taking full advantage of its array of nozzles. The shop uses nitrogen assist gas when cutting stainless steel, aluminum and galvanized, and oxygen to cut carbon steel.

“We used to order three 200-liter tanks of liquid oxygen per month and now we’re averaging just less than one full tank per month,” shares Baxley. “And, our liquid-nitrogen consumption has dropped from as many as 20 200-liter tanks per month down to just 12 per month. All told we’re saving as much as $1000/month just in gas consumption.” MF