Knotless Netting from NET Systems

Dieter Loibner | Professional BoatBuilder Magazine

In NET Systems’ 100-mesh looms, 804 radially arranged bobbins weave an UltraCross net. Half rotate clockwise, while the other half rotate counterclockwise.

It’s a safe guess that nets have been around for at least 10,000 years. These simple, practical tools have found countless uses and become essential to many human endeavors, including fishing, ball and speed sports, cargo transport, the military, and multihull sailing.

I paid a visit to NET Systems Inc. (NET is the acronym for Nor’Eastern Trawl), which occupies a cluster of nondescript industrial buildings in a forest clearing along Highway 305 on Bainbridge Island, Washington. The company was founded in 1978 by Gary Loverich and Tom Croker, who both hail from Bainbridge but worked at Seattle Marine and thought that selling integrated trawl fishing systems might be a promising niche. To research improvements before the age of waterproof GoPro cameras, they donned mask, fins, wetsuits, and scuba gear to take a close-up look at the fishing gear in action.

They didn’t just tinker with trawl design but also introduced UltraCross (UC) knotless netting, made by Nichimo Co., Ltd of Japan, to the Alaskan fishing market. This is a unique four-strand, braided, knotless construction, which produces significantly less drag (due to the elimination of extra material required in knotted nets), thus reducing the towing power required or increasing the size of the net, which translates into catching more fish. Instead of using traditional knotted nylon or polyethylene line, UC netting can be made with lighter and stronger Dyneema fibers spun into twine, which is automatically woven into a net by intersecting with other strands on a specialized loom.

Dieter Loibner | Professional BoatBuilder Magazine

Xzalivar White, a 33-year company veteran at NET Systems

NET Systems and Nichimo formed Superior Netting Products to market the product and manufacture UC netting on Bainbridge, primarily for commercial fishing in the Pacific Northwest and Alaska. “The first loom came over [from Japan] in 1992,” said Xzalivar White, a 33-year company veteran who is the purchasing manager and helps with operations. “We started with one and now have nine of these looms.” Seven are 100-mesh-wide-producing looms that work with twines with 1.2mm–5.4mm (0.005–0.213) diameters, while the largest machine (code named Big Dog “because it’s always hungry,” according to White) is the only such loom in North America, manufacturing 6mm–13mm (0.236–0.51) twine.

The newest loom produces 200-mesh-wide sheets with a typical mesh size of 85mm (3.35) BK (between the knots).

Triumphs of mechanical engineering, these looms require trained operators to maintain and lubricate them for uninterrupted operation. Seen from above, they resemble the air intake of a jet engine, with half of the 804 radially arranged bobbins on the 100-mesh looms rotating clockwise along their longitudinal axis, the other half counterclockwise, spitting out the finished net in the center of the loom. The mesmerizing, precisely choreographed process is managed by a mechanical controller and overlaid by a loud metallic soundtrack.

COURTESY NET SYSTEMS

A bobbin can hold 1,200m (0.75 mile) of Dyneema fiber

Discussing the process, White also offered staggering numbers: Each bobbin is loaded with up to 1,200m (0.75 mile) of raw Dyneema fiber before it is inserted into its casing, meaning that one loom with 804 bobbins uses 964.8 km (600 miles) of fiber to make netting, roughly equal to the driving distance from Salem, Oregon, to San Francisco, California. Once a net is out of the loom, it goes through pre-inspection (check and repair), and coating (basically getting dipped in a polyurethane solution) before being spread in a mechanical stretcher chamber to “set the memory” (polyethylene nets are treated in a steam chamber). It must pass final quality assurance and documentation prior to packaging and shipping.

As an example for multihull applications, NET Systems lists UC knotless netting sheets made with Dyneema fibers with a silver-colored coating (which eventually turns golden from UV exposure) or pure-pigmented black Dyneema. The netting has 42mm (1.66) BK mesh size and is made with 20-ply 3mm-diameter (0.12) twine with a breaking strength of approximately 862 lbs (392 kg). A typical sheet measures 100 x 130 meshes, covers an area of about 10 x 13 (3m x 4m) and weighs about 14 lbs (6.35 kg). The netting is diamond shaped (hung on the bias), borderless, and has a raw-cut edge.

Depending on the choice of Dyneema, the cost of this sheet presently ranges from $850 to nearly $1,100, but discerning customers pony up. The mainstay of NET Systems’ business remains the commercial fishing industry, which purchases trawls, but the company also supplies UC for barrier netting through its distributor, Sportsfield Specialties, to Major League Baseball franchises to use behind home plate. In addition, barrier netting was approved for use by some NHL clubs to keep errant pucks from hitting spectators in the stands. This netting has to be strong and light, and uses very thin Dyneema yarn “because it has to be 95% invisible, so it won’t disturb the view,” White said.

COURTESY NET SYSTEMS

UltraCross netting with black Dyneema fiber is used for baseball backstops and along first- and third-base foul lines.

Right around the time when the founders sold the firm to Nichimo in the mid-1990s, NET Systems started supplying nets for the 60 (18.3m) offshore racing trimaran (ORMA 60) used as a prop in the movie Waterworld. Later it worked with Marathon Racing, the team of the late solo sailor and adventurer Steve Fossett, and racing outfits like the French Groupama team and the Swiss Alinghi syndicate, but also with production and custom builders like Gunboat, HH Catamarans, and Chris White.

Among its high-profile yacht-racing clientele is Oracle Racing, which fitted its America’s Cup–winning multihulls with a customized version of UltraCross with 50mm (2) square openings x 16 ply, or 2.7mm (0.1) diameter. “Oracle Racing was new to the multihull world during the America’s Cup in 2010 at Valencia, Spain, and sought to find the most advanced netting product to outfit the trimaran that would go on to win the Cup,” said Chris Sitzenstock, who worked for the team as a boatbuilder and logistics manager. For safety, light weight, and the lack of wear, he said that UltraCross netting “ticked all the boxes.” At the next Cup in 2013 in San Francisco, NET Systems’ products became an integral part of the AC72 and AC45 class rule, Sitzenstock added.

COURTESY NET SYSTEMS

This textbook installation of a multihull trampoline is done with UltraCross Dyneema netting.

Back at the factory, White told me the story of a hair-raising skydiving stunt that made the Guiness Book of World Records in 2016, when Luke Aikins plunged 25,000 (7,600m) from a plane toward Earth without wearing a wingsuit or a parachute, landing in a 10,000-sq-ft (929m2) net made by NET Systems. Watching Aikins plummet from the sky at terminal velocity and twist onto his back the instant before hitting the net is still a goose bumps moment seven years later. He did not bounce at all, because the net was suspended and slacked off at impact to safely catch and envelop him.

Dieter Loibner | Professional BoatBuilder Magazine

NET Systems’ steel trawl doors deflect water flow and open nets laterally.

Despite all the modern machinery that produces UltraCross netting, NET Systems also provides traditional knotted nets, which are machine-made and imported, e.g., from India. The company occasionally runs a conventional loom loaded with traditional nylon or a more abrasion-resistant polyethylene line. Knotted netting is still used in the scallop fishery and to build normed (standardized) research trawls for the National Oceanic and Atmospheric Administration. Assembly requires skilled manual labor to splice the netting to stout Dyneema rib lines that form the framework of a trawl net. Mike Bucsit, 57, who joined the company in the late 1980s, is among the longest-serving NET Systems employees and was busy finishing a chafer pouch for the cod-end of a trawl with 6mm (0.24) polyethylene line. “In this work, you need to know how to sew, lace, and tie knots, something that I learned on the job,” he said.

Dieter Loibner | Professional BoatBuilder Magazine

Polyethylene line is used for a knotted trawl net, processed on a traditional loom.

Trawl nets use different-size mesh and can incorporate excluders or flaps in the back-end design to help release unwanted bycatch, White explained before showing me the metal shop, where the “doors” are being made. These are in essence heavy steel foils of different shapes and sizes deployed via cable for redirecting water flow at the front end of the trawl to help open the net horizontally. “You have to find a sweet spot, so they don’t stall, which is why sensors are used to measure the door angle,” White explained. Finally, up on the sewing floor, he demonstrated the steps of squaring netting panels by stitching them together by hand, turning them 45° before cutting to make them square.

NET Systems Inc., 7910 NE Day Rd., Bainbridge Island, WA 98110 USA, tel. 206–842–5623, net-sys.com.

—Dieter Loibner