I believe that you can buy wheels from Witmers Coach Shop and some other places. I built mine and am relatively satisfied with the results despite the trouble and worrying that went in to it. Building the wheels was the most intimidating part of my howitzer project as I lack the knowledge, skills, tools, and brains of the old time wheelwrights. I took some pictures of the process and may post them someday when I learn how to add pictures to posts.
The equipment I used consisted of a lathe, a drill press, a hand drill motor, a belt sander, a jig, a wheel template, and a jig saw. The material I used for the hubs and felloes was laminated oak. The spokes I bought from Witmer's.
The first things that I did were to lathe out the hubs using the local high school's lathe. I made a template for the twelve felloes out of some 1/8" Masonite and carefully cut them on a band saw. A friend made an indexed jig to mount the hub for drilling the mortises for the spokes. I wanted the wheel to appear similar to an original, which was dished, without having to deal with boxing the axle. I did this by making the angle on the outside of the hub equal to what was required to dish the wheel which would allow the spoke to be mounted without alteration. The drill press table was set to this angle and the mortises drilled. I used a one inch bolt for the axle with flanged bronze bushings for bearings. I drilled the axle shaft hole with a Forstner bit and a hole saw.
To assemble the wheel, I first drew the wheel on a piece of 4'X4' plywood using a 1X2 as a compass. I then cut out the center of another 4'X4' piece to the outside diameter of the wheels in which I could set the felloes. I set these two pieces together and indexed them so I could take them apart and put them back together. These I placed on the floor on top of a couple of 2X4's. Then I cut the center out the center of the first piece to tightly accept the hub and adjusted the height of the hub to the proper angle. Then I mounted the spokes to the hub and individually trimmed them to fit the inside diameter of the felloes. That done, I used a lot of Gorilla Glue to set them and the felloes in place using the drawing on the bottom board and being careful to prevent adhesion to the template.
After drying, I removed the wheels from the template and drilled the felloes in order to pin the spokes to the felloes with 5/16" bolts that were glued in place. This obviated the necessity of mortising the felloes and making a tenon on an angle at the outer end of the spoke. After that, I took them to my neighborhood blacksmith where we mounted the tire and secured it with some 1/4" countersunk machine screws.
This might seem weird, but I have never made a wheel before or know anyone who has. Nevertheless, I now have a couple of more or less original looking sturdy wheels on which sits my mountain howitzer. Any questions?
