Windsurfing Magazine

kristin
2010-02-24 12:56:07 | 2158 views | 6 Comments

Windsurfing has a rich history of home-brewed inventions. A well-equipped garage was the birthplace of the board that Kevin Pritchard used to end the 12 year world domination of Bjorn Dunkerbeck on the PWA tour. There are still opportunities for creative people to come up with inventions/improvements to windsurfing as our sport advances. Even the most knowledgeable people admit there is always room for improvement. Technology is not picky of its birthplace. Great ideas can be born from big well funded companies or from humble locations like one’s garage. Today, the home-brew or garage band mentality is alive and well. WindSurfing spoke with some key designers and engineers that are making their own equipment (on both small and large scales) in efficient and compact areas (yes, sometimes out of their own garage). We spoke to them with regard to what advances they are making, success (as well as failures) and the difficulties of doing what they are doing. It was a pleasure to talk with Mike Zajicek, Peter Ifju, Bill Hansen, Chris Radkowski and Ben Bamer about the big progress they are making in little amounts of space. Some of the common themes to these people’s success include 1) a solid network of key customers/team riders to provide feedback on designs, 2) quality time on the water trying out their inventions, 3) a passion to bring their technology to the next level and 4) an open mindedness and/or willingness to try new approaches in an attempt to learn more/improve over previous designs. In addition to this article, you are invited check out the links to podcasts with each of these people to dive even deeper into the details.

Few people can claim they have made the world’s fastest boards. Mike Zajicek is a San Francisco Bay shaper who produces some of the finest boards available today. Mike provided boards for Kevin Pritchard who, in 2000, used them to stop Bjorn Dunkerbeck’s 12 year domination of the PWA racing circuit as well as winning the 2001 Formula World Championship in Brazil. In addition to Kevin, Mike has shaped for other members of ‘THE TEAM’ Phil McGain and Scott Fenton, as well as Matt Pritchard (who rode one of Mike’s board to win the 1995 US National Championship), Jimmy Diaz and Finian Maynard. Bic Sport used Mike’s shapes as the basis for their Formula 90/100 designs (after winning the 2001 World Championship). Mike operates out of a very organized and efficient space that most people would refer to as a garage.

The fact that he operates out of a garage like shop does not prevent him from using state of the art materials (including carbon, Kevlar, Technora, Spectra) and techniques (like vacuum bagging) to bring the art of boardmaking to a new level. The small size of his one man operation, has allowed him to thrive in the economic fluctuations that have effected the windsurfing industry. Even with the Dow Jones stuttering, Mike’s waiting list is close to six months long. Many San Francisco Bay locals use his equipment since it’s incredibly durable. By using wood veneer laminated over over PVC foam, Mike’s boards are designed to survive the rigors of jumping over the ‘voodoo’ chop that wreaks havoc and destruction on many other boards that are raced in the high winds and the severe currents that are formed from the millions of gallons of tidal water that flow under the Golden Gate Bridge multiple times a day. Mike made his first custom windsurfing board in 1978. He’s been doing it full time since 1986 and has an extensive network of riders to get feedback from (as well as spending a lot of quality time racing against or tuning with others (Mike is one of the most successful racers in the US and a force to be reckoned with whenever he’s on the racecourse)). So what is Mike tinkering with lately? Styrofoam densities, playing with the shape and perfecting the installation of boxes and inserts into his boards. Mike goes over every square inch with his hands and eyes to make sure there are no manufacturing mishaps. Although Mike does not point to a specific breakthrough, he likens his board lineage to the gradual improvements that the car industry has gone through to get better and better each year. Since 2005, it’s mainly the shape that has changed that defines the improved performance for his latest model. Quicker to plane up and easier to handle are primary goals that Mike strived to achieve by adjusting details of increasing size in some areas, shaving off other areas, placement of bevels, making a shallower cut out and putting a friendlier deck under your heel (which was born out from his day after day sailing/tuning on San Francisco Bay with prototypes). If Mike makes a change in a prototype that he does not like, he’ll make another one, another one and another one until he likes it. If he likes it, he puts it into production, like with his L8 (which was his registered formula board for 2008), and he did not want to change anything about it (and feels is the best shape he’s made ever). (20:55)

What do you get when you combine some of the fastest racers in San Francisco Bay, a fin market that has astronomical prices and waiting lists with a national championship that breaks one’s favorite fin after placing second on the first day? For Chris Radkowski, Al Mirel, Ben Bamer and Bob Kdruna, the answer was obvious: form the F4 fin company. When racing in San Francisco Bay, if one does not have a good fin, it’s impossible to place well in the fleet. Here is a prime example where necessity was the mother of invention. Chris Radkowski is a former Olympic trialist/division II longboard racer who now spends a lot of time giving the formula fleet a run for their money.

Al Mirel is the two time Friday Night Series Champion out of the St. Francis YC on San Francisco Bay. Ben Bamer was the only guy beating Seth Besse at the Formula North American Championship on SF Bay in 2007 before his ‘magic’ fin broke during a race (Seth was basically dominating the fleet and easily won both the formula and slalom events).

Bob rounds out the bunch as an active formula racer and energetic team member of the F4 company. These men have synergized their skills and abilities to create some of the fastest fins in the formula fleet. They work out of a small garage and have been focusing on the optimal flex characteristics that can make a fin crazy fast. Being from the San Francisco Bay and with Ben Bamer at 6’3” and 220LBS, strength is a very important characteristic as well. Things started out when Chris posed the question “How hard can it be to make a really good fin?” They contacted Boogie (Burkhard Vierth) of C3 fin company and he helped them create a formula fin mold (C3 no longer does formula fins and is now focused on slalom and speed fins using CNC G10 technology). The fin creation process at F4 starts out by cutting carbon fabric based on special templates that are designed to work with their fin molds. There are a lot of different layers (different materials and orientations) that go into every fin. They have three different molds for three different types of fins to start from. Everything gets cut and laid in by hand in a specific and precise order (small differences here can make for big differences in fin performance on the water). The fin is then cured using proprietary pressure and heat parameters. One then needs to put the blade in a base, pot it, trim it, finish it and drill it before it’s ready to go (an approximate two day process). Longitudinal flex, torsional flex, rake, length, where you cut off the fin in the base or the tip are some of the variables that are optimized. With composite materials, one can adjust and fine tune the parameters of the fin. Luckily there is a fleet of local racers who are able to tune everyday and provide almost instantaneous feedback to converge on an ideal fin.

On the other side of the nation, we have Peter Ifju creating some incredible racing fins as well. In addition to being a competitive racer, Peter is a professor of Mechanical & Aerospace engineering at the University of Florida where he creates 5 inch long micro-aerial vehicles (tiny, battery-powered airplanes) that could be deployed from a soldier’s backpack to scan surrounding area and see what’s over the next hill (pretty neat stuff for only two ounces)!

Since Peter has a PHD in Engineering, one would expect him to know it all. I really appreciated his honesty and truthfulness when he told me he really does not understand all the aspects of fin dynamics (even though he’s been working on it for some time) and there is a lot left to learn. For me, I think that is the inspiration that drives Peter and others to learn more.. This gives people working out of garages or their homes the opportunity to make significant advances. Peter lives in Florida where getting all that one can get from a large fin and large sail allows one to win races. The fin length he has focused on the most is the 70cm (which is the biggest the formula class rules allow). By using special materials and layup technique, Peter is able to create a very soft fin that does not break (or at least is very hard to break). He chose an elliptical leading edge and straight trailing edge (to allow him to finish out the fin easier and more accurately per his design intent). On his computer, Peter (and his students) played around with a bunch of different foils with computational fluid dynamic simulations and picked a foil that best fit his objectives (i.e. maximizing the lift to drag ratio for the foil and delay stall (or spinout)) and then permuting the twist and bend characteristics of the materials he uses.

To make further advances, Peter does a lot of trial and error. Scientists call this ‘empirical’ testing (as opposed theoretical analysis done on blackboards or computers). Peter calls himself an empiricist since he does so much trial and error testing as well as collect feedback from others who use his fins (even if they don’t like the fin as he’s interested in learning about the wrong turns down the road as well as the right turns). Learning to control the twist and flex of the fin under load by orienting the fibers of the fin material in the correct way to take advantage of bend-twist coupling are areas Peter feels he’s making advancements in and he’s able to leverage his knowledge in composites theory for this.

One of the challenges Peter faces is precisely defining the objective of the problem he’s trying to solve in a form that suits the theoretical models he’s expert in. Things like control are probably equally important as efficiency. On a formula board you want a lot of control, range and be able to push the fin. Things like spin out and the laminar flow attachment to the water can be completely outside the set of equations of his theoretical model. Sometimes Peter thinks he can make a fin that is controllable and slippery but it tends to spin out (which is flow separation or stall from an eddy that builds up resulting in losing lift and increasing your drag substantially). This can happen when the deformation of the fin is inappropriate for all of the initial design objectives used in the theoretical model. Peter finds it’s hard to meet all the objectives of a fin. It’s easy to meet one or two of them but not all. (16:24)

Bill Hansen says his research and development department is his Apple laptop. Bill has been making sails for windsurfing since the ‘80’s, was founder of WindWing sails and is now heading up the design for Hansen sails. Logistically speaking, Hansen sails is a little bit of the Gorge (where his partner Doug Beaman resides), a little bit Oakland (where his partner Mike Percey resides), a little bit of the far east (where the sails are manufactured) and a lot of time on the water from Hansen Sails riders. Bill’s approach is non-traditional and actually starts with concept sketches using Adobe Illustrator (known more for it’s graphic arts power and not considered an engineering tool). The sketches get fleshed out with all the engineering details of a real sail (from planform to batten placement to tack location and all the way to color coordination (which Bill thinks is super important as he feels windsurfers are very visual people).

He then takes his Illustrator file and exports it to a CAD package so that he can communicate directly with his Far East manufacturers for the real sails. Bill is a very humble man and is not eager to take credit even when credit is due. Bill is widely acknowledged as being the inventor of the ‘chop top’ sail in windsurfing and pioneering high aspect full batten sails. In the era of pointy top triangular sails with only partial battens and long booms (i.e the original windsurfer from the 80’s), Bill created a full batten sail with a radically shorter boom (which proved to be a real asset for control and comfort in high wind areas like San Francisco Bay). His latest invention is the Hansen Compliant Leech technology (or HCL). HCL allows for the leech of the sail to dynamically adjust itself during gusts or lulls. Any speed sailor or racer will tell you that a proper stance is one of the keys to going fast. In any speed run or race, there are going to be lulls and gusts that normal sails require a sailor to get out of their optimal stance and adjust for the lighter or heavier pressure. This is where HCL can pay off. Instead of the sailor doing the adjusting (and getting out of her strong stance), the compliant leech automatically adjusts for the pressure and the sailor’s stance can stay in the ‘speed zone’. Here is how the HCL works: along the leech of the sail, there are relatively softer panels as compared to the normal mylar sail material (these are the black V shaped things in the right of the sail in the illustration). During a gust, the soft material stretches and depowers the sail. During the lulls, the soft material tightens up to form a more powerful sail. How much of a difference can this make? Since windsurfing happens at such high speeds, any sliver of speed difference can make significant differences. For example, in a race that lasts 20 mins and boards travel around 20 mph (a low estimate for Formula racing (slalom and speed sailing are much faster)), a difference as slight as 1/10 of a single percent can mean reaching the finish line 35 feet ahead of the pack. Thus any small speed advantage can have big impacts while racing your buddies or on the race course.

Another advantage of the HCL technology is comfort. Current San Francisco Bay Cal Cup champion, Mike Percey, used to have sore shoulders after a full day of racing or training (and Mike is a very tough sailor able to hold down huge sails in big breeze). By using HCL technology, Mike’s shoulder pain is a thing of the past. The ride in choppy and gusty conditions is noticeably smoother due to HCL technology translating into more time on the water with less fatigue. While this was not a design criteria when Bill optimized the material selection for the HCL panels, it’s a wonderfully positive artifact.

If you liked what you read above, check out the podcasts below for even more in depth coverage:
homepage.mac.com/sailing/ml_interview_08.mp3
homepage.mac.com/sailing/peter_ifju_fins.mp3
homepage.mac.com/sailing/bill_hansen.mp3 – bonus coverage of Bard Chrisman, former King of the Bay
homepage.mac.com/sailing/f4fins.MP4