was attached to the combination machine was starting to show its age a bit more. Replacement parts for
the tower were getting hard to find, and with each
year that passed, the fresh-faced technicians that
were available for service calls lacked an in-depth
knowledge about the tower and its components.
Driven by members of the manufacturing team
who were excited to take on new technology, Aronson made the decision to replace the older laser/
punch. A team of four employees spent early 2016
researching the sheet metal fabrication market to
find a replacement. Based on some feedback from
a trusted adviser who had spent some time in the
metal fabricating industry and their own investigation, Aronson and his team purchased a Prima
Power LPe6f laser/punch combination machine in
the summer of 2016.
Following are the reasons that a laser/punch
combo works for P&A Metal Fab and why it might
work for other fabricators as well.
No. 1: It’s all about the flexibility.
After clearing out a 60- by 100-foot space for the new
equipment and about 10 weeks of installation, P&A
Metal Fab started “making some decent parts with
it,” Aronson said. Anything 10 gauge or thinner was
sent to the combination machine for processing.
“It’s the product mix that the machine can handle.
There’s just tremendous flexibility,” he said. “For ex-
ample, we can do forming on it. It’s like a little press
One of the examples that Aronson used to dem-
onstrate the machine’s flexibility was a part for a
customer in the gaming industry. This gaming unit
door, made of 0.060-in. aluminum and about 2 by 2
feet in size, had several holes that were punched on
it and some embossed features, which could easily
be taken care of with the right tool. The fiber laser
could then rapidly cut the large part from the sheet
once the internal features were cut and created.
“This is definitely the right tool for us,” Aronson
said (see Figure 1).
He added that P&A Metal Fab is doing quite a bit
of tapping on its new laser/punch as well (see
Figure 2). This is not being done with a tapping tool
that attaches to the machine, however. Aronson
said he purchased a large-station tapping tool that
holds up to six different taps and accompanying
software. (The Prima Power turret has 20 stations,
with some stations being able to accommodate
multitools. The smallest station is 1.25 in.) While not
an inexpensive investment, the tooling has been
P&A Metal Fab is using tap tooling so frequently on
parts processed on its laser/punch combination
machine that it purchased backup tooling to avoid too
much downtime should something occur to the tooling
in the turret.
The two towers with 17 cassettes for material and parts storage keep the combination system producing even
when operators may not be around to superviser it.
Burns Machinery built the first prototype in
2014, and the company sold its first official system in October 2015. The PSA nitrogen generator separates nitrogen molecules from a compressed air feed. Activated carbon, which Burns
describes as looking like broken pencil lead, is
the material used to separate the molecules.
As the compressed air makes its way through
the carbon molecular sieve, oxygen molecules
are captured, and nitrogen molecules reach the
top. That pure nitrogen is then fed into another
tower. When the nitrogen is transferred, the
other tower releases the captured oxygen into
the room. The process then repeats itself every
60 seconds when the generator is in use.
As Burns Machinery gained more experience
generating its own nitrogen, it learned that if
you try to increase the flow through the generator, you get a drop in purity.
“The problem with typical laser applications
is that you might be cutting 16-gauge stainless
in the morning and 0.50-in. aluminum in the af-
ternoon. The flow rates are radically different,”
Burns said. “For those two cuts, 16-gauge stain-
less will take about 1,000 cubic feet per hour,
and that 0.50-in. aluminum cut is going to take
5,000 cubic feet per hour.
“On our conventional generator, I get four
nines [ 99. 99 percent] or five nines [ 99.999 per-
cent] purity with low rates, but when I try to cut
the heavy material with a big nozzle, my purity
can drop down to two nines [ 99 percent],” he
continued. “That has an effect on the cut quali-
ty, especially on stainless steel. The other alloys
don’t seem to be bothered much at all by the
drop in purity. But with stainless steel in partic-
ular, you can start to see a deterioration in the
cut as you cut below three nines [ 99. 9 percent]
Since most job shops, like his own, rarely run
the same type of material and the same thickness
for an entire shift, Burns and his engineers devel-
oped a way to deliver increased flow rates for the
thick cutting jobs. They decided to store it.
More specifically, they are taking 99. 99 per-
cent to 99.999 percent pure nitrogen from the
low-pressure nitrogen storage tank, boosting
it to 4,300 PSI with the help of a high-pressure
pump, and storing that nitrogen in high-pres-
sure cylinders that feed the fiber laser cutting
machine. A bank of cylinders taking up a 4-sq.-
ft. footprint can provide two days’ worth of
Burns said that once a PSA nitrogen gen-
erator is in place, a fabricator really only has to
keep up with how much cubic feet of nitrogen
was consumed. Being that the generator can
run around the clock, the fabricator can rest as-
sured that the nitrogen will be replenished for
the morning shift.
With the only real ongoing cost to run the
generator being the energy required to operate
the compressed air source, Burns said that the
return on investment for this type of system is
measured in months. Those fabricators that are
used to buying cylinders of pure nitrogen will
definitely recognize the savings, he added.
Meanwhile, Burns’ shop is using the nitrogen
10 hours a day. Any performance improvements
in the system will be shared with users. Like all
fabricators, they are looking continuously to
find a better way.