A Look At Engineered Percussion

//A Look At Engineered Percussion

A Look At Engineered Percussion

Reprinted with permission of Modern Drummer magazine. August 1994.

By Rick Van Horn

Engineered Percussion produces the Axis line of bass drum pedals. It’s the brainchild of Darrell Johnston, a drummer who combined some diverse interests — and a couple of fortuitous breaks — into an innovative manufacturing operation.

Darrell started playing drums at the age of twelve after moving to the L.A. valley from a small town in Montana. (“The culture shock was tremendous,” he recalls.) He played in various bands while in junior high and high school. By the time he was nineteen, he had become a drum teacher. He enrolled in college as a percussion major, but was disappointed when he discovered that the goal of the program was to develop music teachers, not performers. So Darrell wound up concentrating on other academic interests. After leaving college, he was faced with the question of where to go with his life. “I was twenty-two,” says Darrell, “and I’d been playing drums for about ten years. I realized that although I had worked hard at drumming, I really didn’t have the talent necessary to make it ‘big.’ I figured I’d better look for something else I could depend on. So like thousands of young men before me, I went to my father and said, ‘Dad, I need a job.’”

Darrell went to work with his dad — himself an inventor and manufacturer — and also with a gunsmith named Clarence Revilla. “Clarence had a little machine shop,” recalls Darrell. “He inspired me with the power — and the fun — of working with machines and making things. So in 1979 my dad and I decided to see if we could make any money doing contract machine work.

“When you’re a contractor supplying manufacturers with machine parts,” Darrell continues, “you first bid the job. Then you get the blueprints, buy the materials, produce the parts, and submit those parts to the manufacturer. If there are any deviations from the specs, the manufacturer will reject the parts, and you won’t get paid. So in the first couple of years I learned how to make sure the quality was there.”

Then one day, an event that Darrell terms a “godsend” too lace. An engineer named Joseph Smith walked into the shop. Smith had created a drilling machine that had brought him great success in the manufacturing field. He had blueprints for some parts for a new machine he was building, and he asked Darrell to make samples of those parts. Smith was so pleased with Darrell’s work that he gave him the order for all of the parts for the machine. As time went on, Joe Smith became Darrell’s mentor — helping him to acquire a state-of-the-art milling machine and teaching him more about designing component parts. More importantly, Smith got Darrell thinking about getting out of the contracting business and into developing his own products.

Then, while at a club one evening, Darrell saw a drummer laying an all-electronic setup — including some electronic trigger pedals. “When I saw the pedals,” he recalls, “I thought, ‘Gosh, I could make something like those in my shop.’ That’s how I got started building pedals. That same drummer was kind enough to send me a couple of transducers. I had no idea how they worked; he had to show me how to hook them up to the phone jacks.”

Darrell’s first product was the beater less E-Pedal. A radical departure from traditional bass drum pedal design, it bore a greater resemblance to a guitar volume pedal. As Darrell explains, “I wanted to make a pedal that was a s light and smooth as possible. Unfortunately, because there was no weight or resistance behind its action, most people thought it was too light. Drummers were used to that weight and resistance; it was part of their technique. Don Lombardi (president of Drum Workshop) saw my pedal one day and told me that while the pedal seemed to be pretty good, drummers wouldn’t want to re-learn their skills in order to play it. And he was absolutely right. It holds true with any technological development: If it’s not user-friendly, it’s not going to be successful. But at the same time, people told me that I should consider entering the acoustic market, because the electronic market was limited anyway. So I spent the next year and a half developing an acoustic bass drum pedal.”

By the 1989 NAMM show Darrell had a prototype for an acoustic pedal. Again it was fairly radical: It utilized a wheel that followed a cam track under the pedal to advance the beater. “I pursued the concept for at least a year,” says Darrell, “building twenty different versions of it. During that time I connected with a lot of great players for help with the development of the pedal. The final failure of that design happened on night with Tommy Aldridge at a rehearsal for Whitesnake. After the rehearsal we gave Tommy the pedals I had built. Right away I could see that it just wasn’t working. Tommy was kind; he just said, ‘Well, they’re kinda slow on the uptake.’

“I was really heartbroken,” Darrell continues, “and it was very difficult for me to take all the designs I’d worked on and throw them away. But I had involved myself with these great drummers, ant at that point it was either go through with it or become the biggest joke the industry had ever seen. That was the motivation that kept me going forward. Ironically, within hours of deciding to start over, the concept for the variable drive system and features of the Axis pedal just popped into my mind. I had solved all the problems of variable leveraging with the cam concept of my original design; I just had to apply it in a different fashion to make a workable pedal.”

Darrell built twenty of the Axis pedals as they are now configured. He sent one to Modern Drummer for review and the rest to the drummers who had helped in their development. This was around 1990. Approaching drum shops and music stores of the rest of that year generated orders for 150 pedals. “By the 1991 NAMM show,” Darrell recalls, smiling, “the MD review of the Axis pedal had helped to flood us with orders. We were backlogged until the summer of 1993. We’ve been producing as fast as we can to keep up with the demand. We’re only now at a point where our production is keeping up with the orders.”

Reluctant to let go of the idea of an electronic pedal completely, Darrell found a way to add triggering capabilities to his new acoustic pedal design. “On the original E-Pedal,” says Darrell, “the player stepped on a piezo transducer buried in a block of material under the pedal itself. With the Axis-E, the piezo is under a steel plate set in a small block mounted alongside the column of the pedal. Instead of the entire pedal stomping on it, it’s struck by a spring-loaded impact pin as the pedal is depressed. The pin makes secure and accurate contact, but without many pounds of pressure behind it. Column-mounting the trigger kept the footboard and clamping area clear, kept the trigger impact from being too severe, and also gave me the opportunity to be able to offer conversion from a regular Axis to an Axis-E with just a bolt-on upgrade kit. That sort of modulariaty has always been one of our criteria for product design.”

After the single Axis pedal made its mark, Darrell turned his attention toward a double version. The focus of that development was the universal joints used ton the connecting axle. “I couldn’t find and U-joints that really were good enough,” says Darrell. “so I decided to analyze how U-joints were made and what makes them work well or not. What had proven so effective in the way the Axis pedals were built was that they had that smooth, zero-backlash, ball-bearing action. So in my engineering studies I started looking at how spherical shapes interface with flat and tapered surfaces. That eventually gave me the design for the U-joints that we now use.”

Once the double pedal was designed, Darrell was eager to offer a version specifically for left-handed (or left-footed_ players. “I really hated telling left-handed drummers that we didn’t have a left-footed pedal version available,” he recalls. “One day I realized that all I had to do was build a bracket to connect the drive shaft to each pedal differently, and I could offer a left-footed version without having to change any parts at all in the basic pedals.”

Whether double or single, on of the most notable characteristics of Axis pedals is the number of component parts needed to construct them. When asked how many parts are in a single pedal, Darrell replies, “About thirty-five. The double pedal includes all the parts for two singles, plus the components involved with the drive shaft. There are a lot of pieces involved.”

All of those parts are manufactured in Engineered Percussion’s machine shop. “If I had been able to afford it,” says Darrell, “I probably would have gone out and gotten casting — because it’s quicker to cast parts than to machine them. But in those days I wanted to keep the work in our own ship, and ma chining is what we do. Now the machined nature of our pedal has become our trademark.”

But isn’t it more expensive to make the pedals that way? “Yes,” Darrell admits. “But we’re now at a point where the ship is specialized at producing just these parts. In manufacturing, the more you make of one thing, the better and faster you get at it and the more cost-efficient it becomes. Since about 1991 we’ve been able to have enough business just doing the Axis pedals.

“We’ve always run the company on a shorter profit margin than I think most people are willing to do,” Darrell continues. “And that’s come about through my fear of being overpriced. But it’s also a dedication to the idea that the customer deserves something that’s built as well as it can possible be. I learned from my contracting experience that an improperly made part could cost me a fortune. So quality control is a major element of everything we do. One of the great joys of my life is knowing that we give this our best and that people appreciate that.”

Pedal Production

Parts for Axis pedals are created from metal stock in a variety of forms: extruded flat shapes, rounds, and bars. Most of the material used is flawless, dense-grain aluminum: axles, pins, and rods are cut from 12’ bars of stainless steel. Any necessary machine groves are cut on lathes. Bass drum beaters start out as 1 ¾” solid black Delrin (a form of hard plastic). They’re saw-cut, turned on a lathe, and hand-painted. Then they’re fitted onto shafts cut from hardened stainless steel stock.

“Our footboard starts out as flat stock that we have cut to size,” Darrell explains. “It goes into the CNC (Computer Numerical Controlled) machining center, which is totally programmable. That’s the machine that Joe Smith got me. It cuts out the contour of the pedal plate, mills in the Axis name, and drills all the holes necessary for attaching the footboard to the rest of the pedal.”

After the parts are shaped, they’re put into a “vibratory tumbler” that rolls them in a polishing medium to give them a uniform polished surface. Exceptions to that are the pedal plates and baseboards, which are specially sanded to give them a “line grain” surface. Tumbled or sanded parts are then sent out to be anodized; giving them a gunmetal gray color and providing protection against tarnish and wear. Anodized parts then return to be used in assembly.

“I want to build some fixtures in the coming year that will allow us to assemble in a more automated fashion,” says Darrell “but for the time being it’s all done by hand. It’s a matter of putting all the sub-assemblies and individual parts together properly, using lots of little screws. We prefer allen set screws over other fasteners because they’re stronger. It’s more work, naturally, to assemble the pedals this way — but we believe it results in a better product. There’s nothing in our pedals that drummers can’t fix — should they ever need to — out in the field with standard, non-metric, hardware-store stuff.”

An Axis pedal is a very labor-intensive product. Although they are not actually built that way, if a single worker were to assemble pedals all day long by himself he could probably only turn out ten or so in a day. Current production averages about three hundred pedals per month. “It’s a lot of work,” comments Darrell, “and the guys here are all specially trained in the machining jobs necessary. In this kind of work, having some job variety is very important, because any one production job can get tedious. That tedium can result in a reduction of output quality. So we break things up and have everybody do a little bit of everything. That keeps the mood a little bit brighter.”

The Axis Hi-Hat

Based on the success of the Axis bass drum pedal, Darrell wanted to incorporate the advantages of ball-bearing action into the design for the hi-hat introduced by Engineered Percussion this past January. But hile virtually all of the movement on a bass drum pedal is rotational, the most important movement in a hi-hat is back and forth (or “reciprocating”). “The problem is,” Darrell explains, “that the load that you want to have reciprocate — the hi-hat pull-rod — has to be supported by rolling balls. You want those balls positioned so that the tangent surfaces offer not slop — but are still free to roll without any resistance. In essence, it’s a rod sliding through a tube — but to achieve that with rolling action is not as easy as you might think.”

Darrell spent the summer of 1993 studying the rolling concept. He first utilized a system of steel bearings: They worked well, but were very noisy. So he created a tube grooved with three pockets filled with Delrin balls. As the hi-hat pull rod moves back and forth, the balls roll up and down within their pockets, providing a smooth, quiet action. “We use tow of the bearing systems in the hi-hat,” explains Darrell, “one at the bottom and one near the upper end, to support the rod and keep it straight. There is no moving part n the hi-hat that isn’t supported by ball bearings.”

Darrell’s first hi-hat prototype was essentially a remote, without any legs. But he knew he’d need to have a legged stand in order to market the hi-hat successfully. So he turned to another well-known drum-product inventor: randy May. “I built the hi-hat around Randy’s Advanced Tripod system,” says Darrell. “I wanted our hi-hat to be able to tip in any direction, and the legs of the ATS stand are able to slide independently in order to facilitate that. It can also be used in a legless fashion simply by sliding the legs off.”

In order to accommodate the tilting capability of the hi-hat, Darrell also had to come up with tilting capability for the linkage. “The motion of the footboard and the primary linkage — which includes the variable drive lever — is on a universal so it can swivel. There’s another universal up at the top. There’s also a special three-point clutch that allows the cymbals to be set flat on a tilting shaft.”

A special aspect of the Axis hi-hat design has to do with pedal “feel.” “one of the things that I found with my own playing studies,” says Darrell, “was that after I developed a good double-pedal technique, I became much more conscious of the difference between the feel of the hi-hat and that of the left bass drum pedal. With a bass drum pedal, as you depress the footboard you meet a lot of resistance in order to get that beater swinging. But once it starts swinging and the inertia is there, it carries itself. With a hi-hat, there’s little or no feeling of resistance because gravity is already pulling everything down. Your hi-hat spring is fighting that, but it doesn’t build up inertia as the pedal comes down, so the feeling is totally different. With the design of the Axis hi-hat, every attempt has been made to make it feel — or at least make it able to feel — like a regular bass drum pedal, by means of the linear adjustment system. The object is to give drummers the option to obtain a consistent response from all of their pedals, whether bass drum or hi-hat.”

Engineered Percussion Today

Engineered Percussion currently lists over 250 dealers in the U.S., along with several foreign distributors. “My fears of being priced too high for the market were not realized,” says Darrell. “And I think the reason for that is that when a person buys a drum-set for anywhere from $1,5000 to $10,000, a foot pedal that’s priced $50 more than the norm really doesn’t seem that much of an impediment. And one of the good things about our pedals is that there’s enough of a difference in performance and features to allow just about anybody to get the most out of them. Our sales have been great.

“Of course,” Darrell says, smiling, “we’re very small when compared to the major overseas hardware manufacturers. I like to think of Engineered Percussion as the little weed in the corner of the garden. Hopefully we’re tough enough that they can’t weed us out of there. Basically we’re seven people in a couple thousand square feet of production space doing our best to make a real mark and produce the best stuff we can.”