Wheel steering

LouisSenior (27K)
Luis steering off A Guarda
One of the things we liked about Razzmatazz was her tiller steering, which was, of course, superbly sensitive. However, the steering position was extremely uncomfortable for any extended period. There was no comfortable seat, and no way we could see of fitting one and still leaving it possible to steer. And the helmsman had to sit facing sideways, with his neck twisted to look forward. In rough weather, steering was too much like hard work. And the position was very exposed, so that the helmsman got drenched by any spray coming over.

We decided that the only solution was to change to wheel steering, with 2 wheels either side mounted on the bulkhead.

Steering (99K)
The design

My design was like this. Large (0.75m dia) wheels are mounted in front of the cockpit seats either side. They spin on mounts bolted directly to the aft cabin windows. Concentric with each wheel is an inner pulley to drive the steering cable. The cable makes a 400º turn round one steering wheel pulley, rises over an idler pulley above the cabin door, to another the other side of the door, to the other steering wheel pulley, makes a 400º turn, goes down through holes in the cockpit seat and cockpit floor to an idler pulley, runs aft along the hull to an idler pulley just aft of the rear cross-beam, up to an idler pulley on the cross-beam, and thence to a car on a rack mounted centrally on the cross-beam. Tie rods run from the car to stub tillers on each rudder.

The steering wheels and all pulleys are mounted on ball bearings.

I couldn't find any wheels for sale anything like what I wanted, and those I could find around this size were very, very expensive. So, I decided to make my own! Given that this required buying a lathe and making suitable tube bending equipment, this approach certainly didn't save any money. But it gave me a lot of fun!

WheelHub3 (15K)
Wheel hub drawing
Wheel (38K)
A finished wheel
SteeringCar2 (29K)
Steering car on its track

The wheel hubs are made up as a double-decker aluminium sandwich, with fillings of plastic balls. The wheel rims are 19mm tube, bent progressively through rollers. The cables are 4mm Dyneema. The final steering rack was made from a stainless strip, 25mm x 3mm, and the car has PTFE sliders above and below, with push rods linking to the tiller.