David Nelson's Web Site
Steam Ferry Trillium
The Trillium is a very unique and historic ferry that was built in Toronto in 1910 by Polson Iron Works and used to carry passengers between the city of Toronto and the Toronto Islands. She was decommissioned in 1957 then restored to operating condition in 1974. Today she continues to operate as part of the Toronto ferry fleet and usually runs on weekends when passenger volumes are high.
The Trillium is 150 feet long, has a molded breadth of 30 feet, an extreme breadth of 47 feet and depth of 8 feet. She was designed to carry 1450 passengers. This was reduced to 955 later. She was powered by a double compound steam engine which had a stroke of 48", the high pressure cylinder had a 17.5" bore and the low pressure cylinder a bore of 34".
December 22, 2019
The model will be built at a scale of 1:48 which will give it dimensions of 37.25" long, 11.5" wide at it's extreme and 2" deep. The engine will have a stroke of 1.25", the bore of the high pressure cylinder will be 0.36" and the low pressure cylinder 0.71". My plan is the have the engine operate on compressed air using the same valves and links as is used on the full size vessel.
I considered the paddle wheels to be the most complex and demanding part of the model so decided to start there. This took three months to complete.
These paddle wheels are feathered which means the paddle boards do not follow the curvature of the wheel. They are near vertical when they enter the water then pivot so that they are vertical as they travel through the water. The round arms you see on the facing side of the wheel pictured above are what causes the boards to pivot back and forth.
To make all of this happen it required 98 pieces of metal, 8 paddle boards, 128 0.040" diameter bolts with nuts and 230 0.022" diameter rivets on each of the wheels.