The Secret is Out Rotary is Still In

Copyright © 2009 by Davis Multimedia, Int'l. All Rights Reserved.
As Printed in April 2009, Volume 34, No. 10 of The Engravers Journal

Diamond engraving is an excellent marking method for all kinds of metal. Silver and gold charm bracelets from Lillian Vernon Corp., Rye, NY..

  Rotary engraving is an economical way to mark glass and metal awards and giftware items. Photo courtesy of Roland DGA Corp., Irvine, CA.

   Years ago, engravers had a decision to make. Should they buy one of those high-tech laser engraving systems to supplement their engraving business? Will it be worth the extra investment, and just how will it supplement the business? At that time, you didn’t have to insert the word “rotary” to precede the word “engraving”. It was just a given that the word engraving meant “rotary”!
   Interestingly, that whole scenario has more or less flip-flopped. Today, most recognition professionals, particularly those who are relatively new to the business, own at least one laser engraving system that functions as the shop’s workhorse. So the question for today’s newer business owners (less than about 5 years) is not “Should I buy a laser?” Rather the question is “Should I buy a rotary engraving machine?”
Rotary Engraving Equipment
   For the sake of all those people who are relatively new to the business, rotary engraving (technically known as “mechanical” engraving) is the process of using a spinning cutter in a motorized spindle to cut into material, either completely through the substrate to create cut out shapes or holes, or at a predetermined depth to create engraved grooves that form characters and graphics. Diamond drag engraving is similar to rotary engraving in that you can use the same machine but you use a diamond-tipped, non-rotating cutter to cut into the material (usually metal). Either way, the process is based upon feeding or pushing a cutting tool through the material to make a cut via material removal.
   There are two general types of rotary engraving machines: manual, also known as pantographs, and computerized. Using a pantograph machine, you manually lower the cutter into the material and then hand trace a master template or a row of grooved master copy (type) letters, causing the text or design to be cut or routed into the substrate with a cutter.
   Computerized engraving machines use software, sophisticated electronic controls and stepper motors to mechanically lower the cutter and move it along the X and Y axes to engrave. Although most people in the industry have moved towards computerized engraving, manual machines are still popular and used for certain jobs such as jewelry, roundwork (tankards, vases, mugs, etc.) and valuable pieces such as family heirlooms.
   There are a wide variety of computerized engraving machines available to suit your applications, ranging from small countertop systems that take up less than one square foot of table space to systems capable of engraving rings, gifts and cylindrical objects to large flat table systems that can engrave a large quantity of badges or signs at one time.
   All of the major machine manufacturers, including Gravograph (Duluth, GA), Newing-Hall (Toledo, OH), Roland DGA (Irvine, CA), Vision Engraving Systems (Phoenix, AZ) and Xenetech Global (Baton Rouge, LA), offer a complete line of computerized engraving machines in a variety of sizes and configurations. The main differences between these systems are cost, size, capabilities and features.

   Generally speaking, smaller computerized machines have an engraving area of around 4" x 3" to 9" x 12" and range in cost from $5,000-$8,000. These machines are designed for engraving items such as jewelry, award plates, small gifts, pens, single badges and small industrial plates and tags. Mid-sized engraving systems have a larger engraving area, e.g. in the range of 12" x 12" to 16" x 12" and have a price tag of around $10,000-$20,000. Mid-sized machines can do everything a smaller system can, plus larger gift items, signs and industrial parts. Large rotary engraving systems typically feature a movable “bridge” that travels across the table allowing you to engrave very large items or multiple items at one time, such as a batch of badges, signs or nameplates laid out in columns and rows. These machines typically have a 24" x 48" engraving area or larger, depending on the manufacturer, with prices ranging anywhere from $12,000-$30,000.
   One of the major differences between laser and rotary (aside from using a laser beam vs. a mechanical cutter to cut or mark) is the fact that rotary engraving is strictly a “vector” based process where the cutter always must follow a tool path. Most lasers today, of course, offer both “vector” and “raster” engraving, i.e. where an image is generated by having the beam go back and forth over the surface as the laser “fires” a series of pulses to make the cut or mark.
Rotary Engraving Software
   A major link to successful computerized engraving is the software. A good software package allows you to quickly and easily create text and typically simplified graphics that can be engraved on your computerized system. While most computerized engraving systems have an open architecture which allows them to run off of third-party software packages such as CorelDRAW, there are also engraving-specific programs available. All of the major machine manufacturers, for example, offer some type of proprietary software designed for use with their equipment, but you can also purchase engraving-specific programs from a software developer such as CADlink Technology Corporation, Ottawa, Ont., Canada. Engraving programs are typically available in different “levels” ranging from beginner to advanced so you can select an application based on your needs.
   The advantage of engraving software is that it gives you access to a wide variety of engraving-specific applications, such as auto layout (a feature that lets you automatically create attractive award, gift and sign layouts based on basic information that you input) and multiple plate engraving (the ability to automatically engrave multiple plates from one setup, e.g. a series of name badges) in addition to a wide selection of engraving fonts and graphics that are specially designed for engraving.
   These programs are sometimes compatible with other graphics programs, such as CorelDRAW, so you can import and/or scan in graphics and convert them into a format suitable for engraving. There are also many features for specific applications, such as creating ADA signage or engraving seals, which walk you through these types of jobs.
   The one disadvantage to these engraving-specific software programs is that they can cost twice as much, or more, than some of the popular off-the-shelf programs. While some users may feel the available features and time saved with engraving-specific programs eventually pay for themselves, others may have a hard time justifying the additional cost if they can do the same jobs, though possibly with a workaround, with a less expensive program.


A top-loading rotary spindle engraving glass. Photo courtesy of Vision Engraving Systems.   A pen holding jig is just one computerized engraving accessory that can lighten your workload! Photo courtesy of Vision Engraving Systems.

Rotary Engraving Components
   While a laser works with a focused, intense beam of light as its “cutting tool,” rotary engravers use actual cutters to get the job done. Cutters are made from different materials and in different configurations depending on the material, application and overall look you want to achieve. Here’s an overview of the rotary engraving cutters available along with the basic components you need to rotary engrave.
   Spindles—The spindle is the mechanism that holds the cutter in place during engraving. Most of the engraving machines used in this industry feature “top-loading” spindles, meaning that a cutter is inserted into the top of the spindle and (usually) secured with a threaded knob. Cutters for top-loading spindles are available in various shank sizes, including 1/8", 11/64", 1/4", 4mm and 6mm diameters as well as various lengths to fit the spindle. The advantage of top-loading spindles is that you can quickly and easily load and unload cutters.
   Collet spindles are also available, particularly on larger, industrial type machines. This type of spindle features a collet (similar to a drill chuck) that tightens around either a bottom- or top-loading cutter to hold it in place. This type of spindle is more rigid and precise, but involves more time to change cutters.
   Diamond Gravers—A diamond graver consists of a small, conical-shaped industrial diamond set into the tip of a metal cutter shank. These non-rotating cutters can be inserted into a rotary spindle (and used with the spindle motor turned off) or used with a spindle designed specifically for diamond engraving. You can also use a diamond drag adaptor, which is essentially a small diamond cutter that attaches to the bottom of a rotary spindle.
   A non-rotating diamond “graver” drags across the material surface (hence the name diamond drag engraving) to create a shallow, fine cut with a bright, polished finish. This type of cutter is used to engrave into metal such as brass, aluminum and pewter gift items, trophy and plaque plates, jewelry, etc. The beauty of a diamond graver is it can cut any and all kinds of metal—everything from gold and silver to hardened tool steel.
   Diamond gravers are available with various tip angles. A 120-130 degree angle is used for general purpose engraving, a 90 degree angle cuts deeper and is well-suited for hard metals or epoxy coatings (coated pens, for example) and a broader angle, e.g. 140 degrees, makes a shallow, wide cut that works well on soft metals like pewter or gold.
   Rotary Cutters—Rotating engraving cutters are typically manufactured from high speed steel or (micrograin) tungsten carbide, although carbide cutters are generally more popular for engraving applications because of their toughness and durability. The cutters used for the widest range of engraving applications have a conical profile with a half-round blank configuration, which means that the cutter is split in half and ground with a single, angled cutting edge. Quarter-round cutters are also available for special applications such as engraving hard metals.
   Conical cutters are ground in different tip sizes, and the tip size determines the width of the cut. Cutters are also available with different “clearance angles”, depending on the material being engraved. Softer materials, for instance, typically require a larger clearance angle to give the cleanest cut and to let the material chips escape during engraving. You can also purchase or grind cutters with different cutting angles for different applications. For example, the standard cutting angle is 30 degrees (60 degree included angle), but you might choose a cutter with a 45 degree cutting angle (90 degrees included angle) to create a deep V-groove for a dramatic effect in a material like acrylic.
   When used to engrave into materials like plastic, metal, wood, solid surface material, acrylic, etc., a conical cutter produces a V-shaped cut with a flat bottom. When used to cut out shapes, e.g. cutting name badges out of plastic engraving stock, these cutters leave a smooth and attractive beveled edge.
   The other common type of rotary cutter is a parallel cutter. Instead of a conical shape, a parallel cutter has a straight cutting edge that is parallel to the cutter’s axis of rotation. When used to engrave, this type of cutter produces cuts with straight walls and a flat bottom. When used to cut completely through the material, the result is a cutout with straight side edges, as opposed to angled edges, giving an effect that is particularly desired for applications such as control panel engraving where the panel needs to fit over dials, knobs and keys.
   Burnishing Cutters—A burnishing cutter is a rotating cutter with a multi-faceted tip. These cutters are used in conjunction with a burnishing adaptor, a spring-loaded mechanism that fits on top of the cutter and allows it to “float” across the material surface. “Burnishing” essentially involves rubbing away the top surface of the material while polishing the base material. The tool tip is wider than a typical diamond graver and comes in various tip sizes to provide good proportioning for different sized letters.
   Carbide burnishers are typically used on coated, colored or marbled brass, aluminum and steel. For example, on lacquer-coated metal, the cutter removes the lacquer coating to expose the bright, shiny metal underneath. Diamond-tipped burnishers are also available and can be used for aluminum, steel, silver, titanium and pewter, but they are also an excellent tool for rotary engraving glass. As with other cutters, various tip sizes are available and the width of the tip determines the width of the cut. These tools produce a smooth, clean finish and also can result in shorter engraving times, e.g. when engraving large characters.
   Specialty Cutters—There is also a wide variety of specialty cutters available which are designed for specific applications. For instance, spiral flute cutters and “end mills” have spiral-shaped cutting edges, similar to a drill bit. These are used for drilling and engraving hard materials such as stainless steel. There are also special cutters available for certain jobs such as engraving Braille dot holes for ADA Braille signage. Other applications where special cutters are used include engraving eyeglasses, bowling balls, stencils and plastic pens.
   Depth Noses—When you are diamond engraving, the depth of cut is regulated by the pressure the cutter exerts against the material, which is typically controlled with a spring tension adjustment on the spindle. When rotary engraving, however, the primary method for regulating how deep you cut is with a depth regulator nose.
   The depth nose attaches to the bottom of a rotary spindle. Using the spindle’s micrometer dial, you can adjust how far the tip of the cutter protrudes through the nose and, thus, how deeply the cutter penetrates the material. While engraving, the nose rides along the surface of the material under tension from the spindle compression spring. This helps to provide a uniform cutting depth, even if the material isn’t perfectly flat (which in many cases, particularly when engraving plastic, it isn’t).
   Although plastic (nylon) noses are available for engraving very soft plastics, most noses are made of metal. Various sizes (varying in the clearance hole diameter) are available to accommodate different cutter sizes and for different applications. For instance, a large nose is convenient when making most cuts since the cutter can extend further through the nose opening. Smaller noses have a conical shape and are well-suited for engraving on curved surfaces because the smaller size conforms better to the irregular surface.
   A vacuum “foot” or adaptor is also an option. A vacuum adaptor consists of a nose cone that is attached to a vacuum chip removal system that removes material chips created during engraving. This is useful for keeping the work area clean, e.g. when engraving plastic or making deep cuts. In some cases, nose cones are not used, mostly if there is a risk of damaging the material, e.g. deep engraving on metal.

A conical/tapered cutter (left) and a parallel cutter (right), courtesy of Antares, Inc., Horsham, PA.   Rotary engraved silver platter. Photo courtesy of Gravograph, Duluth, GA.

   Holding Jigs—Unlike laser engraving where only a beam of light touches the material, rotary engraving involves an actual cutter exerting force against the material being engraved. As such, the item being engraved needs to be “held” or secured in the engraving machine to prevent it from moving during engraving. This is accomplished using various clamps and fixtures, often referred to as holding jigs, which are available from machine manufacturers and distributors.
   There are a variety of holding jigs available depending on the type of machine you have and the type of work you’re clamping. For example, you can hold flat items and material sheets using clamps, sticky mats (typically a rubber mat with a sticky surface) or double-faced adhesive tape. There are also jigs designed to hold specific items including flat plates, pens, medals, medallions, watches, bracelets, rings, award plaques, door knockers, silver trays, tire gauges, ID bracelets and more.
   Most manufacturers also offer “universal” jigs that will hold a variety of odd-shaped items by inserting pins into a series of holes in the jigs to secure the item in addition to small vises that can be clamped to a flat table to hold small jewelry and gift items. It’s probably safe to say that with a basic selection of about 8-10 sets of holding jigs, you can probably hold 98 percent of engravable items that go through most industry-based shops.
So What’s the Appeal?
   Even though laser engraving may rule in many if not most applications that engraving shops may encounter, experienced retailers say businesses can really benefit from having both technologies available to them. Laser engraving has earned the reputation of being a very versatile, user-friendly engraving process. For most dealers, this is the method of choice when it comes to engraving plastic, acrylic, glass, stone, leather and solid surface material. Rotary engraving, however, is also a versatile process with the ability to engrave many of these materials but with one very distinct advantage: it will work with most kinds of metal.
   Unlike CO2 laser engraving systems, rotary engravers can mark on just about any type of machinable bare metal including aluminum, brass, stainless steel, silver, gold, titanium and platinum. CO2 lasers, on the other hand, can only produce a mark on specially coated metals by removing a colored surface coating to expose the metal underneath, e.g. such as that on anodized aluminum or lacquer-coated brass, or by first applying a special laser-fusible coating like Cermark which allows the laser to produce a blackened effect on the metal surface. There are also some special-purpose photo-reactive metals around which are laserable.
   One of the major advantages of rotary engraving is versatility. As just mentioned, this engraving method allows you to engrave a wide variety of products. The awards market, of course, is a major area for rotary engravers and includes products such as trophy plates, plaque plates, medals and medallions, corporate gifts and acrylic awards. And while lasers are also great for engraving most award products, they’re not necessarily as well suited for many traditional engravable gift items such as jewelry and metal products like tankards, flasks, ID bracelets, charms, compacts, boxes, luggage tags, etc.
   Signage is another area where both lasers and rotary engravers have a foothold. However, when it comes to ADA signage, rotary engraving holds the advantage because it’s easier to create the required raised lettering and Braille dots. This engraving method allows you to use one machine to create the letter cutouts and then switch the cutter, drill holes and place “Raster” method Braille beads directly into the holes, which is something you really can’t do with a laser.
   You also have to consider the fact that laser and rotary engraving produce much different “looks” and, in many cases, it’s the look of rotary engraving that customers want. Rotary machines actually cut into the material to produce text and images while lasers simply mark or burn the text and images into the material. Many times rotary engraving is desirable for appearance and permanence. In addition, many of the traditional rotary fonts, such as connecting script and interlocking monograms, give a personal “feel” that isn’t quite the same as using some TrueType fonts often used in laser engraving.
The Learning Curve
   Although some engravers may shy away from rotary engraving due to the perceived learning curve associated with cutters, depthing, speeds and feeds, etc., it really is all relative. Both laser and rotary engraving processes require that you learn the mechanics of the machine, whether it’s installing a rotary cutter and setting the engraving depth or choosing the correct speed, power and other related settings on a laser to achieve the desired look.
   There is also a learning curve associated with both engraving techniques when it comes to the software you use, whether it’s CorelDRAW, a proprietary engraving package or a third-party engraving-specific program. In fact, some retailers claim that it’s actually more difficult to learn CorelDRAW than it is to become familiar with engraving software.
A Retailer’s View
   Many retailers in the R&I Industry offer both rotary and laser engraving services in their businesses. Here’s a sample of some of the businesses, along with some testimony on how and why they use these two applications to complement each other.


Rotary engraving can be used to personalize a wide variety of metals. Photo courtesy of Gravograph. Signage and ID tags are popular rotary engraving markets. Photo courtesy of Johnson Plastics, Minneapolis, MN. An easily attached burnishing adaptor from Antares, Inc.

   R & W Engraving—Roger Bastarache has operated R&W Engraving in Biddeford, ME, for 25 years. He started the business with rotary engraving equipment and purchased his first laser engraving system about a year and a half ago. “We still use our three rotary engraving machines constantly, every day, along with our laser engraver,” he says.
   Bastarache explains that even though the laser allows them to easily engrave wood, glass and acrylic, he feels the laser is limited as to the type of engraving that can be achieved. For instance, Bastarache uses his rotary engraving machines to engrave any type of metal whether it’s brass or anodized aluminum nameplates. An added advantage is that the rotary engraver allows engraving deep into the metal so he can paint fill the engraved areas. “With Cermark, we are able to blacken many metals, but the only color available is black and the material that we use this chemical on must have no surface finish in order to be blackened,” he notes.
   Bastarache also says that they achieve better results rotary engraving colored brass plates, such as blue and red, using a rotating diamond burnishing cutter. “Blue and red are colors that still do not engrave well with a laser engraving machine,” he says, adding he also uses his rotary equipment to engrave plastics that are not specifically labeled “laser engravable.”
   Great Lakes Trophies & Awards—Ed Duprey opened his rotary engraving business in Garden City, MI, in 1995 and purchased his first laser engraving system about a year later. Today he operates his business with three rotary engraving machines and two laser engraving systems.
   Duprey said he uses his rotary engraving machines strictly for engraving metal, such as trophy brass and aluminum, and for items such as award medals and dog tags. One of Duprey’s rotary machines is used specifically for diamond drag engraving. “We use a standard diamond drag that does excellent engraving with fine detail,” he says. The other two machines are preset for burnish engraving. In fact, Duprey said he leaves the cutters and spring tension adjustment set in these machines so when a trophy plate order comes in, they’re all set to go. “I do all of my trophy plates on my rotary engravers because of the easiness of it,” he says. “We can run a whole sheet and just walk away from it.”
   Great Lakes Trophies uses its two laser engraving systems for most other work, including profiling name badges and engraving plastics, acrylic, glass, wood, baseball bats, stainless steel and laserable metal plaque plates. Duprey points out that any job requiring a logo is normally done on a laser because of the ease and quality of working with “raster” graphics, and also because over the years most of the logo artwork is saved in CorelDRAW.
   In addition to flexibility, Duprey points out that having rotary engraving machines on hand is also economical. “If you have the volume, you need at least two engraving machines,” he says. “In our case, purchasing a rotary engraver was a less expensive investment than a laser. Plus, rotary machines are much less expensive to operate. The lasers require an exhaust fan, compressed air (air assist) and they probably use the highest amount of energy in our business. In the end, though, the two systems definitely complement each other. I wouldn’t do without either one!”
   B&B Awards and Recognition—When Tricia Shaw opened the doors to her engraving business in Bloomington, IL, in the late 1990s she strictly offered laser engraving services for her awards-based business. That quickly changed, however, when just a few years later two area colleges began approaching her to engrave plates for their perpetual plaques. In order to match the engraving on the existing plates, they needed a shop with rotary engraving capabilities.
   “We wanted university and school business and they already had plaques with brass plates. You can’t sell them something they don’t want, so we were sending the work out just to get their business,” says Shaw, adding it was better than turning customers away.
   Soon after that experience, Shaw said they added rotary engraving machines to their equipment line up, which helped B&B Awards and Recognition to gain the lucrative business of area colleges and schools. Shaw points out that with rotary engraving, they’re able to charge more because they can charge by the letter as opposed to the square inch as they do with laser engraving, which increases revenue.
   A couple of years ago, B&B Awards and Recognition even purchased a pantograph engraving machine on the advice of an employee who had worked with one for years. Shaw says that piece of equipment makes their business even more flexible by allowing them to engrave round items and some gift merchandise. “It will do anything,” she says. “We have a jewelry store that sends us work that we do on the manual machine such as silver cups. I think we are the only business in town that will engrave items that are not bought here,” she says.
   Like other retailers, Shaw feels that having the ability to offer both rotary and laser engraving opens up more potential job markets and increases your chances of attracting more customers. “The two processes complement each other. There are definitely things that one machine can do that the other can’t. If you want to grow your business, I think you need to have both,” she says.
Some Advice
   If you’re thinking about purchasing a rotary engraving machine or on the verge of doing so, some veteran retailers offer a few words of advice. For example, as with any large purchase, comparison shopping is a must. Duprey recommends attending a trade show and having each machine manufacturer engrave the same job, e.g. 12 or so 1" x 4" trophy plates on a sheet of trophy brass or aluminum. “Compare the speed and the quality, and pay attention to how quiet they are,” he says. “When I went to last year’s Las Vegas show, that’s what I did. Each machine and manufacturer has its pros and cons.”
   Duprey’s second piece of advice is to avoid going too small. “Spend the extra few bucks and get at least a 12" x 24" table. A lot of times people say, ‘I only do my trophy plates in 4" strips,’ but if you get that one job where you do need to engrave a full 12" x 24" sheet then you will have that capability.” He said when he first started looking at rotary machines he wasn’t going to get the larger table, but he was convinced he would need it later and did go bigger. “I am glad I did,” he says.
   Tricia Shaw says she believes it’s important to select a machine with versatility, particularly if you’re new to the business and still trying to define the markets you will be selling to. “Look at the customers you have now and the customers that you want. If you’re going to buy a rotary engraver, buy something that’s going to give you the most uses that you can get out of it,” she says.
   For example, Shaw said she doesn’t think it’s a good idea to buy a machine that can only engrave gifts, especially if you’re just starting out. “Later, if you have defined a market niche and you think you need a specific machine like that then buy it. In the beginning, though, get the one that will do the most for you.”
Conclusion
   If you’ve never considered a rotary engraving machine as part of your business, maybe it’s time you did. As with laser engraving, rotary engraving technology continues to progress. Much of this new technology is in the realm of software which has given a tremendous boost to rotary. Today’s software is intuitive and high tech.
   “Rotary engravers are becoming faster and easier to use,” says Natalie Whitehouse, Marketing Coordinator for Vision Engraving Systems. “Engraving into glassware, giftware, jewelry, ADA signage and industrial engraving on metal are currently very popular. Advanced electronics and new software capabilities allow for faster and more accurate engraving, smoother motion controls and time-saving features.”
   As mentioned earlier, the strength of rotary engraving is versatility. “Rotary engraving machines are particularly well-suited for visually appealing applications that require high quality, low cost and speed,” says Whitehouse. Both laser engraving and rotary engraving have their advantages, and it’s clear that they can make excellent co-workers. Is it time to look at adding rotary engraving capabilities to your laser engraving business?


 

 

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