The EZ-Slalom™ HeavyDuty™ Slalom Course
When you first see the words "heavy duty" the picture that most likely comes to mind is of something massive, strong, and obviously built to last. That's certainly what we think of anyway. Before we could call our permanent slalom course systems "heavy duty" we had to assure ourselves that they would fit the bill. So we researched and tested the materials we use for our EZ-Slalom HeavyDuty courses until we were absolutely certain that we could indeed consider them to be "heavy duty".
At the same time we also took into consideration
the trade-off between structural rigidity, materials strength and
durability, and price. Is it possible to build a better slalom course
than an EZ-Slalom HeavyDuty? In a word,
perhaps. For example we've seen information on the internet from
folks who have built permanent slalom course buoy arms using 2"
square aluminum tubing, steel angle iron, and even 6" aluminum
irrigation pipe! We've heard of folks using 3/8" steel cable
for slalom course mainlines. Is that "better"? It may
posibly be "stronger". Better though?
To build courses such as these the investment
of time and funds is significantly higher than
what you'll invest in a EZ-Slalom HeavyDuty course (which by the
way is warranted against failure of materials or workmanship for
ten full years!). If you want such a course we can definitely build
it for you if you'd like, or we can customize
a mainline or course kit to work with your 2" square aluminum
tubing, 6" aluminum irrrigation pipe, or whatever materials
you choose if you wish to do it that way. Realize though that the
final cost to build such a course will be much
higher than the price of a stock 10-year-warranty EZ-Slalom HeavyDuty
course while the tradeoff between structural strength and price
will likely be well past the point-of-diminishing-returns, at least
in our studied opinion.
So the real question then is this - Do any of our
competitors build a better permanent slalom course than an EZ-Slalom
HeavyDuty? No, they don't. Here's why.
First off, the stainless steel cable we use to build our mainline is the same exact cable our competitors also use. Same size, same strength, same manufacturer, same cable. How do we know this? We purchase our cable from the same supplier our competitors purchase from, who happens to be the largest supplier of such stainless cable in the United States. This mainline cable is 3/32" in diameter (coated to 3/16"diameter using a clear, flexible PVC coating) or about the size of #12 electrical wire. You're wondering how such small cable can possibly be strong enough to hold up under high tension for extended periods of time (several years) while immersed in water? So were we.
The manufacturers break strength rating for this cable is 920 pounds
of tension. Pretty tough stuff, especially considering
it's diminutive size. Not being satisfied with that we went the
extra step of having this cable break strength tested to insure
that it is as tough as advertised as well as to satisfy ourselves
of its strength. To our surprise, despite the manufacturers rating
the cable tested out to be even stronger than advertised! Of over
a dozen samples tested the lowest failure rating for any
of our samples was 1050 pounds of tension, easily well
beyond the amount of tension required to keep your course dead-on
straight. Certainly then, this cable while not being massive in
size is definitely strong enough to meet anyone's definition of
OK, so this cable tests out to over 1000 lbs of break strength.
What does that really mean to the user? To get your course to go
and to remain straight you need to tension the mainline enough that
nothing can cause it to bend or bow. In our testing we've discovered
that a tension of 150 - 200 lbs will get and keep your mainline
fiddle string tight and completely straight in almost all conditions
(a high crossing breeze being the only possible exception - in which
case it's likely too rough to do any skiing anyway). So yes, we
believe that the term "heavy duty" is apt here.
So What Makes Our Mainline Better?
So if we use the exact same stainless steel cable to build our mainlines as everyone else uses, what makes the EZ-Slalom cable mainline different? Two words. Superior engineering.
The most common way to attach two pieces of steel cable together is by crimping them together. No rocket science there. One of the main issues in designing a slalom course mainline is that where the buoy arm attaches to the mainline a connecting system of some sort must be created to stabilize the buoy arm perpendicular (that is, at a 90 degree angle) to the centerline of the mainline. This structure is known as the diamond due to the shape that is created when the buoy arm is attached at this point. The diagram above illustrates what the diamond looks like, how it's constructed, and how the buoy arm attaches to it. Basically you have one cable at the centerline of the course running from diamond to diamond positioning the buoy arms at their correct locations throughout the course. Where the diamond is located (where the buoy arm is attached to the mainline) you have that one cable attaching to two separate cables with each of the two cables attached to the buoy arm at either side of the boat lane section of the buoy arm. See the diagram above for more detail.
How Do Others Do It?
Others attach the mainline's centerline cable to the cable sections
that create the diamond using one crimp at each of the two end points
of the diamond. They're connecting three cables
together at this point, the one centerline cable intersecting with
the two halves of the diamond. This one crimp is required to handle
two different types of tension load, axial load
and radial load. Axial load is the tension
applied to the course's mainline to keep the course straight. Radial
load is the sideways load placed on the crimp by the two
halves of the diamond being spread apart by the buoy arm attached
to it. See the diagram above for details.
Asking one crimp to take these two different types of load
at the same time, and placing that entire load on only one
crimp is asking a lot of that one crimp. Especially
if you're using an aluminum crimp at this point, as our
competition does. Aluminum is a relatively soft metal which when
attached onto a dissimilar metal (the stainless steel) and then
immersed in water (which aluminum crimps are not specifically designed
for) subjects the crimp to galvanic corrosion. This potential
for corrosion in combination with all of that load placed on only
one soft crimp can cause the eventual weakening and/or failure of
How Does EZ-Slalom Do It?
With the EZ-Slalom HeavyDuty mainline we divide that load between two crimps rather than just one. First, we build each of our diamonds separately by using two sections of cable with each cable staggered so that it leaves a tail at each end point of the diamond (see the diagram above). So at the diamond's end points there are only two pieces of cable being attached together, not three. Building the diamond in this manner places the entire radial load on only one crimp at each end point of the diamond. We then attach the remaining tail at each end of the diamond to another cable which runs from diamond to diamond. This second crimp takes the majority of the axial load. Thus we divide the tension load placed onto the cable between two crimps rather than putting it all on just one, lessening the load on each crimp and reducing the likelihood of failure at any crimped point.
The crimps that we use for our EZ-Slalom HD mainline are themselves different as well. Where others use aluminum crimps not specifically designed for marine applications, we use a crimp made from hardened copper and zinc that is manufactured specifically for use in a marine environment. Again, to ensure their strength was up to the necessary standards we've had these crimps laboratory tested with our cable to measure and ensure their resistance to failure under tension. In all of the samples tested these crimps held at least as much tension as the cable did before failure. Plus they're much more resistant to corrosion and therefore much less likely to fail. Better materials combined with better structural engineering, resulting in longer service life of the mainline and reduced likelihood of failure.
HeavyDuty Buoy Lines
We also went beyond the norm to construct our permanent course buoy lines. Rather than going without any shock absorption whatsoever (which transfers more shock and vibration to the mainline and buoy arms, accellerating wear and reducing service life) or just using ordinary shock cord (which has limited service life) we utilize durable large diameter surgical-grade rubber tubing for shock absorption. These buoy lines will last seasons under normal conditions without failures caused by materials breakdown. We don't just tell you they'll last, we back it up with our warranty. Our HeavyDuty buoy lines are standard issue for all of our HeavyDuty permanent courses and HD course kits and can also be added to our portable courses as an option.
That's how we build all of our products at EZ-Slalom. We find the best available materials, combine them into the best engineering designs available, and price our products very competitively.
Best Built! Best Engineered! Best Value! That's why EZ-SLALOM is The Standard in Portable Water Sports Courses!
EZ-Slalom is the OFFICIAL SLALOM COURSE of the INT LEAGUE
and OFFICIAL NATIONAL SPONSOR!
Thank You for taking the time to review our information. If you have a question about something not covered here and would like to request a brochure, additional information, or would like to discuss any issue with us person-to-person please contact us by e-mail to email@example.com or call us toll free at 800-216-4461. We enjoy answering your questions and we'd love to hear from you!