A head on a 3D printer is positioned above the mattress, able to print the following job—maybe your subsequent press brake punch or die. Jakub Zerdzicki/iStock/Getty Photos Plus
For a century, press brake instruments have been carved from software metal. Some had been the standard planer-style instruments manufactured from an X-Y reference coordinate, and others had been precision-ground to a really tight tolerance. Each had been hardened to counter put on, use, and abuse day after day.
That hasn’t modified, and it’ll most definitely keep that method for a very long time to come back. Nonetheless, the necessity for prototyping and quick runs has shifted demand towards customized tooling—and right here, 3D printing might play a serious function.
Over the previous couple of months, now we have been studying that the 3D printer sitting on a store bench right this moment could make a working press brake punch or die in only a few hours (not weeks), and for a fraction of the price of metal tooling. Let me be clear: 3D-printed tooling just isn’t right here to switch the metal in your software rack, a minimum of not but anyway. Nonetheless, for prototype, short-run, and one-off forming jobs, 3D-printed tooling for the press brake has a spot. Even some commerce colleges are utilizing 3D-printed press brake instruments for instructing and classroom demonstrations. Within the arms of competent and certified folks, a 3D printer can turn into one other precision software of the commerce.
Why 3D Printing Works
Utilizing additive manufacturing isn’t about being cool; it’s about time. In a conventional situation, you’d name your tooling provider for a quote after which wait a number of days or perhaps weeks for the software to reach. With 3D printing, you’ll be able to mannequin your idea in CAD, slice the file, and hit “print.” Inside a number of hours, you’ll be able to load the software and see the way it behaves on the brake. If it doesn’t work out, you’ll be able to modify the design and hit print once more.
You can also 3D-print instruments when instructing new operators, or in conditions the place manufacturing pace or security issues greater than software longevity. With the best plastic filament and correct printing circumstances, 3D-printed instruments can deal with low- to moderate-tonnage jobs with stunning accuracy.
Filament Choices
Most individuals begin with polylactic acid (PLA). It’s cheap; straightforward to print; and delivers a crisp, clear end. PLA’s stiffness helps preserve correct geometry, and its low shrink price delivers glorious dimensional accuracy proper off the print mattress. For verifying kind angles, creating new die geometries, or checking interference in setups, PLA is ideal.
However PLA is also brittle. It doesn’t like flexing, it softens underneath warmth, and it could possibly’t deal with sustained compression. In different phrases, it’s an ideal studying and fit-check materials, however not for severe bending masses. Below a press brake, even at low tonnage, PLA tends to crack alongside the layer strains.
PETG resists put on higher than PLA, but it surely gained’t match metal and even aluminum. PETG (which stands for polyethylene terephthalate glycol, should you’re curious) can deal with mild air forming of skinny materials, as much as 20-ga. delicate metal, particularly on quick bend lengths. In coaching purposes, PETG punches and dies have been identified to outlive a whole bunch of demonstration bends with out failure.
For purposeful, working 3D-printed tooling, nylon (PA6 or PA12) is on the high of the listing. Nylon filaments, particularly when blended with glass or carbon fibers, produce strong, versatile, and wear-resistant press brake instruments.
Nylon’s toughness permits it to deform underneath stress after which get better, very like urethane. That flexibility spreads the load throughout a broader space, decreasing stress concentrations on the layer strains. It’s additionally supreme for delicate jaws, forming pads, and even versatile die inserts. For customized forming purposes—particularly when marring have to be prevented—nylon tooling will be each sensible and delicate on materials surfaces.
In case you want a plastic punch or die that really works underneath strain, composite filaments are the reply. These are normal polymer bases—like nylon, PETG, and even ABS—infused with quick carbon or glass fibers. The result’s a stiffer, stronger, and extra temperature-resistant materials.
Carbon-fiber nylon, for instance, has roughly twice the stiffness of unfilled nylon and may face up to greater masses with out deflection. In testing, quick punches printed from carbon-fiber nylon have efficiently shaped 16-ga. delicate metal in small V-dies underneath average tonnage. That’s fairly exceptional for a software that comes out of a desktop printer.
One other materials, thermoplastic polyurethane (TPU), is obtainable in a number of durometers (hardnesses) from medium to arduous, and its place on this listing could be very totally different from the opposite filaments we simply mentioned. This materials varies in softness. Meant to deform and deflect, TPU principally acts as a strong hydraulic, much like the urethane pads you would possibly place in dies for sure forming purposes. You push in, and it pushes again equally in all instructions, inflicting the fabric to evolve to the form of no matter’s making use of drive, be it your finger or a press brake punch nostril.
Within the press brake world, TPU can be utilized for every part from creating rectangular or sq. elements to particular sizes or dimensions, or for printing uniquely formed pads that meet particular forming wants or capabilities. (For extra on this subject, you’ll be able to evaluation my columns on forming with urethane from earlier this 12 months.)
Apart from TPU, filament supplies will be annealed. The truth is, usually, they ought to be annealed. We lined some fundamentals in earlier columns, and we’ll delve additional into the annealing course of subsequent month.
The Sensible Hybrid: Plastic Meets Metallic
Even probably the most inflexible polymer will finally put on at high-pressure factors, particularly the punch nostril and die shoulders. Most fashionable printers mean you can pause a print mid-process, insert a special materials, and resume printing proper over it. Meaning we are able to embed wear-resistant metallic inserts precisely the place they’re wanted.
Image a 3D-printed punch: You pause the print simply earlier than the punch nostril layers shut, drop in a size of small-diameter stainless or hardened metal rod, after which resume the print. The machine buries the insert, locking it into place with only some levels of metallic floor uncovered. The metal takes the wear and tear; the printed physique carries the form; and collectively they make a light-weight, hybrid software.
In dies, the identical technique works for shoulder reinforcement. A pair of metallic rods or tubes will be seated the place the fabric slides throughout bending, stopping put on and sustaining constant angles. The print resumes, totally encasing the inserts for a everlasting bond.
Floor End and Friction
The smoothness of a punch and die’s printed floor straight impacts how materials flows throughout bending, in addition to how a lot warmth is generated by the ensuing kinetic friction. A tough, layered end will increase friction and may mar delicate surfaces, reminiscent of aluminum or brushed stainless-steel. To attenuate this, you’ll be able to print finer layer heights, between 0.1 and 0.2 mm, and check out sanding the contact areas calmly with 400-grit paper. You can also apply dry Teflon or silicone spray to cut back drag.
When to Use 3D-Printed Tooling
3D-printed press brake instruments excel in three areas:
- Prototyping, to rapidly show out a component design, bend sequence, or software geometry
- Coaching, to carry out secure, low-cost demonstrations for brand spanking new operators or school rooms
- Quick-run or specialty jobs, which may require customized radii, protecting tooling, or delicate finishes
Apart from this, you’ll be able to 3D-print a bunch of various helpful gadgets, together with jigs, fixtures, and gauging instruments. These embrace go/no-go gauges; positioning or fit-up fixtures; facet gauges and customized backstops; and even small tables that connect to the press brake die to help small elements and preserve operators’ fingertips safely away from the pinch level.
You may print customized crescent wrenches; light-duty clamps; and even precision measurement instruments like radius gauges, thread gauges, guidelines, and protractors. You may even create a set of radius gauges for every operator, or one for every press brake.
In case you are air forming and wish to guarantee you’ll be able to measure the “floated” inside bend radius, print a radius gauge that matches the required radius, and ship it with the job jacket. (As you understand, air forming won’t ever obtain an inside radius that matches a typical set dimension like 1/64 in., 1/32 in., 1/16 in., 1 mm, or 2 mm.) There actually isn’t any restrict to what you’ll be able to construct, apart from the bounds of the filament you’ve gotten chosen.
A Know-how Price Contemplating
3D printing gained’t exchange metal press brake tooling or the abilities of a metal toolmaker, but it surely does current new choices. For the precision sheet metallic commerce, that’s progress price bending towards.
Subsequent month, in addition to delving additional into annealing, we’ll additionally evaluation the particular necessities for the print mattress and glues. And we’ll take a look at sintering, the sintering ballast, and the sintering kiln. When you’ve got constructed press brake punches or dies, or different 3D-printed instruments or fixtures, and want to share what you’ve gotten achieved, good or dangerous, my e mail tackle will be discovered beneath.
