Strut Rudder results

I am quite happy with the improvement in steering provided by the strut rudder. It seems to be far more effective than the dipping rudders in turning the boat. When both a dipping rudder and the strut rudder are used to turn in the desired direction the boat is almost able to be controlled to a reasonable extent. Of course, it is nowhere near as maneuverable as the Cadence and far from the maneuverability of the Escapade, both of which have the advantage of propeller thrust against the rudder. Still, it is an excellent improvement.

I found that the nylon tie was getting abraded by the aluminum on both the rudder and the strut bearing bracket. This was due to the fairly sharp edges on both. I have since rounded the edges of the hole in the rudder through which the nylon tie goes. The strut bearing bracket will have a second nylon tie over which the supporting nylon tie will nest. This way the inner tie can be tightly held to the aluminum bracket and provide a smoother bearing surface for the tie under tension holding the prop shaft to the rudder.

+/- 20 degrees appears to be all that is needed. In fact, turning the rudder slightly less than 20 degrees significantly reduces the aeration of the propeller.

Cruising speed seems to be either unaffected or possibly very slightly slower. However, not having to adjust course by dipping the rudder should make overall speed better.

Will I remove the dipping rudders? Right now I'm not sure. There are times when having the extra rudders for a somewhat tighter turn makes life easier. I also have to see if the nylon ties have an adequate lifespan to place all my trust in the strut rudder. Otherwise, an alternate mechanism or material will have to be used.

I still have to replace the prop shaft with one that is not bent. That project is nearly done as the tubing and rod were cut to proper length and bonded last night with fillet material and cloth. After it has set for two days I'll drill a hole through the diameter of the tubing and insert a stainless pin to make doubly certain they stay together.

I expect cruising speed to be a little higher and be able to maintain it for a longer time.

Work has begun on modifying the dipping rudders to have a 20 to 25 degree angle rather than the 40 degree angle they currently have. This involves cutting the fillet and glass securing the wood pieces to the fiberglass tubing and re-adhering them at the proper angle. This should be done in a week or three.

Meanwhile, I'll give it a try with just the strut rudder for the next race.

Seat cushion and new rudder

I just made and will try out in next week's race seat covers for the foam. While I was going to use garden cloth it appears that stuff isn't quite as strong as I expected. There is a mesh but a lot of the fibers are merely a mat and don't impart much strength.

The material I ended up using is a garden plastic, with push-through perforations every 1/16 inch or so. One side is somewhat slick, but the push-through side is moderately high friction. Anyway, I cut it roughly to size and welded/cut it to final size with the electric shrink wrap sealer. With the perforations pointing outward I think it will drain fairly well. It took all of 10 minutes work, cutting/sealing two sides, turning it inside out, stuffing in the foam and sealing the remaining edge.

This stuff seems to be fairly tough, and should last for quite a while.

I also purchased some "industrial strength" adhesive backed velcro to secure the cushions to the boat. The vertical orientation of the 2 inch wide seat back strips will allow some vertical adjustment to accommodate the position of the PFD. My spine was rather sore after the last two races due to a gap between the cushion and the lower edge of the PFD.


In preparation for the next race I have replaced the prop strut with a foil shaped rudder. The foil is something I found online a couple of years ago for use in making rudders for a different boat. It is aluminum, about 3/8 inch thick at the thickest point, and about 2-3/4 inches wide. Taking some scrap anodized aluminum I salvaged from some ancient office partitions years ago I cut a triangular hole near one end to accommodate the rudder and its intended range of motion port and starboard. This replaces the U-channel prop strut holder previously installed.


I cut a two armed tiller from 1/8 inch aluminum sheet. This has a foil-shaped slot to control the turning of the rudder, and allow it to not impede the rudder from moving vertically.

The foil was cut to about 17 inches length, with a notch cut from the bottom so as to surround the tab supporting the prop strut bearing. A 1/4 inch hole was drilled just above the notch and two holes cut at 1 and two inches from the opposite end. The bottom hole had a heavy duty nylon tie wrap looped through it and the hole in the prop strut bearing tab, with a slight amount of slack enabling the rudder to twist port and starboard.

A 3/4 inch bolt was inserted through the top hole and a nylock nut used to secure it. This is used to prevent the rudder from dropping through the tiller slot.


A small hole was drilled about midway down the rudder. This is to be used when lifting and holding the propeller shaft in its upper position for shore-side transport by inserting a pin.

Another synthetic cord was tied from one tiller arm, threaded through the same dead eyes as are used for the dipping rudder shock cords, stretched to the left grab tube, and back to the other tiller arm through the other dead eye. Control of the strut rudder is by pulling the top of the cord for starboard and by pulling the bottom of the same cord for port.

Due to the width of the strut support the rudder is limited to +/- 20 degrees.


I hope to give it a try this holiday weekend.

If the rudder/strut works, I'll consider replacing it with a lighter wood/aluminum core or glass/foam/aluminum core foil. This would use the original (or equivalent) strut for the core. I might also replace the strut support with one that allows a wider range of motion, e.g., +/- 30 degrees.

If it works really well the dipping rudders will be history. This should reduce the windage steering encountered at the last two races.