Runners. That is a topic that has occupied ten years of discussion on
the DN boards. Read the archives at www.dnamerica.org for a thorough
discussion on choosing, aligning, straightening the edges, etc.. DN
sailors build inventories of specialty runners for decades. There are
many variations in metal, type (depth), profile and grind.

For the WD49, The One set would be hardened steel (or hardened 440C)
with a 90 degree grind with a gentle curve profile from a large radius
on the front. If the runner is set on a flat surface, a 0.008 spacer
will fit under the edge from the front and back, and the pivot will be
above the mid-point between the spacers. The ".008 flat" (distance
between the spacers) would be 16-18 inches. The Two would be for
snow. Stainless steel (hard or soft) taller plates 30" long on the
sides and 26" on the front, and 14 inches of .008 flat. These go through
snow better and can turn better in snow. Two sets means six runners, or
three pairs: Pair of max length, pair of 30 inch plates and one or two 26
inch plates gives several options.

These can be found in the for sale sections of the DN boards sometimes
or at the annual swap meets, coming up soon. You need quarter inch
thickness.

Edges straight and parallel to within 0.002 over 20 inches of running
edge is very very desirable, lots of work getting making it so, and
purchasable.

My opinion, FWIW. This needs to be a sailing variable that is ignored
so you can focus on how to sail these things. You can do this by
buying a quality set of runners from an experienced supplier. It will
cost, however. The rules require max 36 inches, thickness 1/4 inch.
This can be accomplished several ways. Sarns Hardware and Northwinds
sell plate runners with an extruded Al stiffener on the top edge,
suitable for use in a 1 inch wide chock, available from the same
sources. These 36" runners are used on Jet 14 and other iceboats.
They are carbon steel, with a plated side surface for corrosion
control and are finished, shaped and sharpened when received. (Edges
are not ground to the standard set above, but serviceable) These
are good runners. An alternative is to use a stainless steel. 440C
has shown itself to be an excellent alloy in most conditions, and make
a durable runner. The DNs use this material, but their rules require
an "insert" construction to make the runner 36 inches long. These
runners are also within the rules of the WD49 as they are the right
length and can be the right thickness. They are stiffened by a wood
and composite upper body. They are made to other rules which don't
disqualify them from the WD49 rules as well, but have dimensional
constraints that are not relevant to the WD49.

I will be using insert runners on the sides and a "bull nose" plate
runner 30 inches long on the front. I have more than two sets for my
DN collection. My much preferred source for runners is Ron Sherry,
Composite Concepts, 35940 Carlisle, Clinton Township, MI 48035, USA
Tel: 586.790.5557, Fax: 586.792.3374, Email: 2concepts@...

These are priced as follows, for the variants in stiffness and body
shape. Ron supplies them straight and true and regatta ready.


440-C, 30" Bullnose runner (plate) $450.00 plus $30 S&H*
440-C, 36" 1/4" Pressmold Insert $575.00 plus $30 S&H*
440-C, 36" x 1/4" Pressmold Insert w/stiffener $675.00 plus $30 S&H*


Ken