Step 1: Cut all the parts to size according to the list of materials — except for the cab sides (F), which will be cut out in Step 3, below. Use a 1-3/8-inch hole saw to cut out the large, 1-1/4-inch wheels (B); a 1-1/8-inch hole saw to cut out the smaller 1-inch wheels (C) plus an extra for the cab pivot pin lock (T); and a 1-5/8-inch hole saw to cut out the 1-1/2-inch crank wheels (P).
NOTE: If you can’t locate these exact size hole saws, you can use a larger diameter saw to cut them out, then mount them on your drill press and file or sand them down to the smaller sizes you need. The 7/8-inch diameter cab pivot pin lock (T) is made by sanding or filing-down an extra disc that’s been cut out with your 1-1/8-inch diameter hole saw.
Step 2: Make the chassis(A) by first laying out and drilling the 5/16-inch diameter axle holes. Then, use a bandsaw to cut the 30-degree bevels on the ends. Drill the 1-inch diameter by 1-inch deep hole for the cab pivot pin lock (T).