Those that follow the machine tool industry have probably heard the news: in August of 2018, Amada Holdings Co. Ltd. of Japan acquired Marvel Mfg. Co. Inc., maker of the Marvel brand of metal cutting bandsaws, circular saws and ironworkers since 1904.
And while Amada Marvel Inc. may be a new name to those who’ve spent years working with these ubiquitous machine tools, national sales manager Bill Verbrick assures his customers that it’s the same great equipment, but now backed by the largest machine tool builder in the world.
Vertical Benefits
Verbrick also tells manufacturers that to process structural steel, a vertical tilt-frame bandsaw is the best thing since sliced bread.
“In the United States, at least, Marvel’s vertical tilt-frame saws dominate the market,” he says. “Some even refer to any tilt-frame machine as a ‘Marvel-style’ saw; there are that many of them out there. This is especially true with service centers and large fabricating houses, where maximum throughput is a necessity, but the tilt-frame’s slightly higher price tag relative to a horizontal is less of an obstacle.”
Price tag aside, Verbrick is quick to point out that even smaller shops can realize big benefits from a vertical tilt-frame saw, including better blade life, shorter setup times and improved part quality. For the few fab shops that haven’t yet seen the vertical light, there are several reasons to move in that direction.
- Ergonomics: A horizontal saw sits lower to the ground than a vertical, making it more labor-intensive to reach the workpiece and raw material. With a vertical saw, everything is right in front of the operator, at a comfortable work height. Not only is material handling less strenuous, it’s also much easier to line up the blade with a scribe mark for manual sawing.
- Mitering: With most horizontal mitering saws, the blade frame is unable to rotate toward the shuttle, which means the saw can miter in only one direction. This is no big deal for cutting parallelograms, but makes it impossible to cut trapezoids (think picture frames) without flipping the material. Verticals don’t have this limitation.
- Vibration: When a horizontal saw pivots for a miter cut, the blade is typically farther away from the vise. This leads to less support and, therefore, increased vibration, which is a primary reason for premature blade failure. With vertical saws, the blade position relative to the vise never changes, no matter how steep the angle.
- Feed force: Not all horizontal saws are gravity-fed, but those that are tend to underfeed the blade at the start of the cut and overfeed at the end. With a vertical saw, the feed force is consistent throughout the cut.
The downside is that a vertically oriented saw blade makes complete and abrupt contact when engaging the vertical surfaces found on squares and H-beams, thus creating higher cutting forces. The solution is to cant the blade forward a few degrees, something any good tilt-frame vertical saw can do.
This doesn’t mean that horizontal saws don’t have their place, Verbrick notes. For simple, straight-cut slugging of bar stock or tubing, they do an excellent job and are also less expensive, inch for inch, than vertical tilt-frame saws. If a horizontal is chosen, a double-column machine generally provides better results than a scissors-style horizontal, especially with difficult materials or where cutting forces are high, he notes.
“For mitering, however, tilt-frame verticals are absolutely the way to go.”
Making Decisions
One quick glance at the Amada Marvel website reveals several models of vertical tilt-frame saws, each with its own configuration, control and automation options. Where does a potential saw buyer start? And what differentiates these saws from their competition? According to Verbrick, there are several key factors any saw buyer should consider, regardless of whose logo is painted on the machine.
The first and probably biggest decision is whether to go manual, semi-automatic or full auto. In Amada Marvel’s case, the terms are fairly self-explanatory. Manual saws such as the 8-Mark-II require an operator to manually tip the head and advance the raw material, whereas automatic saws like the 800 Series PC3S do everything…well, automatically, and can be programmed to cut whatever angles, lengths and quantities are needed.
“The 8-Mark-III, on the other hand, is considered a semi-automatic machine,” Verbrick says. “The mitering function and column feed are both automatic, but the material must be positioned by hand.”
The type of shuttle mechanism is also significant, at least with automatic saws. Amada Marvel’s are servo-driven and, therefore, can be precisely calibrated, which according to Verbrick, provides far more accurate results than hydraulic shuttles.
Address The Structure
Let’s say you’re sawing a batch of parts from some 6-in.-high H-beam. Some of the cuts are perpendicular, while others are mitered to 45 degrees. What blade should you use?
A fine-pitch blade is the first choice for the thin center section of the H but will quickly load up on the much thicker ends. And once the blade has been tipped for the 45-degree miter cuts, a quick calculation reveals the material thickness has essentially increased by around 40 percent.
One fortuitous outcome of Amada’s acquisition of Marvel Mfg. is the introduction of two new blades designed to address this and other challenges of structural steel sawing. The Amada Marvel Eagle Beak VTR (vertical tilt range) is “an excellent choice for all mitering applications, with a unique 3/6 pitch to accommodate the variety in tooth engagement when cutting structural shapes,” says Bill Verbrick, Amada Marvel national sales manager.
The other new blade is the Eagle Beak SST (structural steel teeth), which addresses the chipping and tooth wear common with interrupted cuts in lightweight structural steel cutting.
“This particular blade has three tooth designs,” Verbrick explains. “A protector tooth prevents over-incision, a very sharp tooth reduces cutting forces and a strong tooth prevents chipping. Both products launched in January and are proprietary to Amada Marvel.”
Direct force sensing electric feed is an important option for shops that cut large quantities of structural steel, to minimize the havoc that varying material profiles play on the blade, and minimum quantity lubrication (MQL) systems eliminate the mess of flood coolant when used with I-beams and tubing.
“Vertical tilt-frame saws aren’t limited to structural steel, but because of their mitering capability, they’re ideal for fabricators,” Verbrick says. “Whatever the application, though, I’m looking forward to the opportunities we as an organization see in joining with Amada and adding their extensive selection of metal cutting saws and saw blades to our offering. It’s been a win-win for both our companies, as well as for our customers.”
