DIY Buoys and Race Course for R/C Sailing

 

By: Mike Eades, Seawind US 089, Wickenburg, AZ (meades@w3az.net)

 

During some correspondence on the Seawind Resource Center Forum it became clear that there are a number of new Seawind owners faced with sailing alone and hopefully finding like souls to start a club. One of the first things they need is a set of buoys or marks from which to set up a racecourse for individual practice or for the first competitive races. I was faced with this problem and found some useful ideas on the Internet from which I have built a successful set, which I use regularly.

 

This note will spell out the materials used, the making and using of the buoys. I apologize for my lack of artistic skills but I hope you can get the information you need.

 

Figure 1 below shows the system in place. It consists of a buoy (A), tethered by line that passes through a split ring (B) with attached lead fishing weights and leads to shore where a spool (C) holding excess line is anchored in the bank.

 

 

A         The Buoy is made up of a piece of tubular foam (12-14 inches long, 2.75 inches diameter with a ½ inch diameter hole running through it) into which a piece of copper tubing (1/2 inch diameter, 12 inches long) is inserted (leaving ~9 inches exposed) and glued with a few drops of CA glue. A small hole, (~1/8 inch diameter) is drilled through the copper tube (~ ½ inch from the end) to attach the line. See Figure 2. The foam is a piece of pool float obtainable from pool suppliers in a variety of colors and lengths.

 

B          The Split Ring and Weights: I used a 1 inch diameter brass (to avoid corrosion) split ring (key ring or similar) on which I threaded 4-6, 2-ounce fishing sinker weights, purchased at any good fishing supplies shop. The ring with weights must be able to slide easily up and down the exposed copper tube on the buoy. See Figure 2.

 

C         The Line and Spool: I found the ideal thing at Home Depot in the builder’s supplies section, an “Empire” 100’ Line Reel with woven Nylon line wound on to a plastic spool, attached to a handle so that the reel can turn while holding the handle. The handle is conveniently shaped to stick in the ground. The manufacturer is Empire Level Mfg. Co., Mukwonago, WI 53149, USA www.empirelevel.com. See Figure 3.

Having produced four or five of these buoy assemblies, tying the line securely to the copper tube, after passing through the split ring, it is time to think about deploying them to set up a racecourse. The recommended full “Olympic” racecourse is shown in Figure 4 and uses 5 Buoys or Marks A-E. A shorter and simpler course can be used eliminating Mark E.

 

To set out a Mark, simply choose a suitable location, lay the buoy on the ground with the split ring and weights up the copper tube against the foam, unreel a length of line on the ground, making sure it will not tangle or foul any snags. Holding the spool handle in one hand and the copper tube of the buoy in the other, throw the buoy out underhand, taking line with it, to the chosen location. If it is done correctly the split ring and weights will slide to the bottom of the pond below the buoy. Reel in excess line until the buoy is held upright and anchor the reel by pushing the handle into the ground. Repeat the process for each buoy, making sure the lines are separated so that they won’t tangle. To recover the buoy, simply reel it in, hoping there are no underwater obstructions for it to snag on.

 

The dimensions of a racecourse depend on the size of pond and number of boats expected to race. The Start-Finish line C-D should be roughly X = N.L; where N is the number of boats and L is their waterline length. So, for 5 Seawinds, X should be about 5 meters or 15 feet. The location of the Weather Mark A and Leeward Mark B are roughly equidistant from the finish line with the Gybe Mark E level with C-D and offset to form a triangle with A and B. See Figure 4.

 

The race consists of a start from C-D line, proceeding to and rounding marks, A, E, B, A, B in order, leaving them to Starboard and finishing at line C-D. If the prevailing wind is blowing mainly in the opposite direction the course would be reversed with the marks left to Port.

 

For competitive racing, AMYA members can purchase an inexpensive AudioTape or CD with 1 and 2 minute countdowns from the AMYA Secretary. An inexpensive, battery operated tape or CD player and you are off to the races!