USS MONITOR
ENGINE BUILD
Part 9 by Vince Cutajar
USS MONITOR
ENGINE BUILD
Part 9 by Vince Cutajar
The USS Monitor was an ‘ironclad’ steam ship which famously saw service in the Civil War in the early 1860s. The ship's engine was designed by John Ericsson as a "vibrating side-lever engine." He had created similar engines before and decided to use the design again because of its advantage for a small, low-riding warship.
Most steam engines of the time had vertical pistons, which occupied a lot of space and made them vulnerable to enemy fire because they were partially above the waterline. In contrast, the Monitor's 30-ton, 400 horsepower engine had pistons that moved horizontally, which reduced the height of the engine and allowed it to be mounted below the waterline.
Although a successful fighting ship the Monitor was not stable in rough seas due to its formidable rotating turret and sank in the early hours of January 1, 1863.
The engine was recovered from the Monitor's wreck site in 2001. It is now resting upside-down in an alkaline solution to inhibit corrosion. Over the coming years, conservators will continue to clean and separate the many different pieces of the engine to preserve them properly.
The first model Monitor was shown at Harrogate in 2014 by Brian Stephenson to the design of Bob Middleton. It was built without castings, like Bob’s other designs. Julius de Waal has produced these CAD drawings for both metric and imperial (see here) versions. Drawings can be downloaded for personal use only.
This one is built to Julius’ metric drawings.
To do the pistons and piston rods I had to go shopping for the material. I need some 5mm stainless rod and cast iron for the pistons. Never bought cast iron locally so was not sure if I would find any. Went to my usual supplier and was pleased to hear that he had cast iron. Only problem that for a 26mm diameter piston I had to buy 40mm diameter! The other problem was that he could not give me a piece of 5mm 316 stainless but a full 3m rod. I thought this was going to be expensive but still got them. And believe it or not it cost me 6 Euro including the cutting.
Took some time polishing the pistons to fit nicely in their respective cylinders. Now I can move the piston by blowing in the inlet port.
The Piston Rod End.
I was not happy with the first piston rod end that I made. This was the second attempt. Started off with a length of 12mm square brass stock. Centre drilled one end for the live centre.
Part one here Part two Part three Part four Part five Part six Part seven Part eight Part nine Part 10 Part 11 Part 12 Part 13 Part 14 Part 15 Part 16 Part 17
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