Restoration’s Final Touches: 2-1/2 HP Ottawa Engine

Peter Rooke finishes restoring his 2-1/2 HP Ottawa engine, including making cart wheels, a drip tray and crank guard – Part 4 of 4


| February/March 2014



Completed 2 1 2 HP Ottawa

Peter Rooke’s completed 2-1/2 HP Ottawa.

Photo by Peter Rooke

Most stationary Ottawa engines were sold without carts. Generally just the engine was shipped to keep down transport costs, and then once received the engine was fitted to any available truck. This made it difficult to get a picture of an original cart to know how to start making one. This was the only time that Ottawa Caretaker Helen Myers, who has since passed away, could not fully help me with an original picture for this engine, although she provided a lot of detail for the next size up but, unfortunately, that was a different style of cart. A plea for help on Smokstak also drew a blank. Helen was able to provide dimensions for the timber for this engine and advised me that the cart would have been similar to the Warner catalog of carts, for which they had a rather indistinct picture. At least this catalog print gave some hard facts, including the specification of the wheel diameters and face sizes.

The cart itself was said to be similar to a Galloway cart, so after studying the catalog picture at some length I came up with the following design, which I believe is a true representation.

Cart wheels

The wheels of the cart had five spokes, the front being 7 inches in diameter and the rear 9 inches, both with 1.50-inch-wide faces. I then drew up plans for both wheels.

To make the hubs of the wheels without wasting a lot of solid bar, I cut four lengths 1.50 inches long from both 0.750-inch and 1-inch NPT pipe. I had to fractionally bore out the inside of the 1-inch pipe on the lathe so that the smaller pipe slid in before I could weld it in place to form a hub for a 0.750-inch axle.

Starting with the smaller wheel, I clamped and centered some 0.250-inch steel plate to the milling table. I would use this to form the basis of the five spokes and ridge under the rim. This provided an opportunity to try out the recently acquired DRO (digital position readout) tool fitted to my mill, so I didn’t mark any reference points on the metal. After centering and drilling a pilot hole in the middle, I used the DRO to drill a series of holes for the corners of the five triangles that would be cut out of the metal. Next, I used a milling cutter to plunge mill between the holes. I bored the central hole for the hub that would be welded in place. I sawed off the surplus metal around the outer edge before turning it to size on the lathe, an overall diameter of 6.5 inches.

To complete the five spokes and give them a cruciform cross section, I fixed tapered bars at 90 degrees on the core plate. Then I cut short lengths of 0.250-inch-thick bar and clamped them on the milling table with a spacer at one end, so it was an easy matter to mill one side to get a tapered profile. I welded these pieces on the core section to complete the spokes.