DN Iceboat Hulls, Spars, Planks, and Runners

CSI DN Iceboat Masts


“I could not have won back to back championships with out this mast. ”
Tomek Zakrzewski P55, Poland,
previous World Champion


”This could be the last mast you will ever need.” Bernd Zeiger G107, Germany


Kit Mast

One Piece

Kit Mast

Two Piece

Complete Mast

One Piece

Complete Mast

One Piece

Winner of Multiple World Championships


The highest performing spar in strength and durability.


Unmatched in quality based on design, process, and choice of materials.


In over 15 years only two have been known to fail. A record no other builder can even dream of!

The development of CSI DN spars has been ongoing for decades. We draw upon a database from many years and hundreds of spars containing flex rates in fore/aft and side/side axes to design each DN spar. All CSI spars are custom engineered to suit the individual sailor’s weight and plank spring rate. Mast weight and VCG are at or near minimum to class rules.

All masts are built of with a state-of-the-art process that involved wrapping layers of s-glass and carbon fiber over a mandrel. Curing is done in an autoclave under pressure to ensure a void-free (in other words, reliable) laminate. Our laminate is the most reliable, durable, and lightest design on the ice.

Masts are available in one piece or unique two-piece design (introduced during the ’98 season) that allow tip sections of varying stiffness to be removed from the highly flexible lower tube. This allows for ease of transport as well as fine tuning capability. The precision slip fit connection requires no fasteners.

Our spars are fitted completely with custom hardware.

The original “T fitting ” hound attachment introduced to the class is aerodynamically clean, providing full articulation, easily connected to the spar without tools.

CSI masts use a custom CNC machined black anodized hardcoat mast step plug with a four position socket adjustment. On the inside, the mastplug contains a square recess into which an optional internal stiffener tube may be rigidly fastened in the proper orientation as needed for varying flex properties.

CSI makes its own custom thrust bearing mast socket fitting. This fitting allows the mast to rotate freely, with almost no friction between the mast step ball and the rig. A must for racing. It uses standard 5/8″ thread, Black hardcoat anodized.

    Construction process Computer engineered laminates using epoxy and glass and carbon pre-pregs over a mandrel producing a non interrupted off axis fibers around mast and perfectly strait uni-directional fibers lengthwise.


    • Available in one piece or two piece (removable tip for transport) layouts.
    • Available complete ready to sail with clear Awl Grip paint or in “Kit” form where everything is supplied, you just need to clean up cured tube and mount supplied hardware.

    Mast features

    • CNC machined Aluminum anodize mast step with custom ball bearing mast socket.
    • Halyard and multi position lock.
    • Gibb tee mast hound with custom spreader bar fitting for shrouds.

    Stiffness Masts are offered in 3 different ranges of stiffness.

    • 3.0:  Softest
    • 4.1:  Medium stiffness and by far the most commonly used mast
    • 5.0:  Stiffest