Almost rolling: The next logical step was wheels and tires - I like to have those set before I do the body mounts - measuring and calculating is fine but, in the end, I want to see
what it looks like!
I decided to take a shortcut and modify some BWA wheels I had on hand. Here's the before and after:
For those interested in the process: I mount a wheel on a piece of 3/32 drill blank and chuck it in a 3/32 collet then face off the front back to the edge of the rib. The depression for the tire is then machined - I used a 60 degree indexable carbide tool perpendicular to the work giving me a 30 degree angle on either side. The wheel front is then hogged out with a 5/16" end mill mounted in the tailstock (could go larger but that is all the chuck will handle. The recess is then finished with a boring bar to a 0.505" ID to suit cut-down Ninco wires as inserts. (I run the boring bar in until I hit the set screw - this messes up the screw and threaded hole but this is not a problem since I subsequently cross-drill the brake drum to take a 1-72 set screw. This allows me to glue the tire on and true it without worrying about access to the mounting screw) The wheel is removed and the axle pushed thru to allow it to be mounted backwards. The rear section was turned down to 0.44" - to make a 14" brake drum. there was a fair amount of back and forth on the dimesions of the wheel, mounting and unmounting various tires until I got the "look" that I wanted:
From left to right: two rear wheels with Ortman 1/32 tires mounted, one cndidate front with and EJ's #15 tire and at far right, the same wheel with a 3/16" cross section O-ring mounted and grond down to provide a flat tread ( More about the O-rings later)
The difference in width is apparent:
Again, left to right: Ortmann, EJ (rounded), O-ring
And finally -
AlFin drums, of course!
The O rings are an experiment - perhaps a bit too rounded for anything later than about 1950 but pretty good earlier than that and, I think, better than most choices for 30's and earlier. They are available in a vast range of cross sections and diameters in fractional inch, decimal inch and metric measurements. I have no idea if they offer any traction at all - not a concern for fronts - but I shall see if they can be coated with RTV silicone such as Permatex Form-A-Gasket to serve as rears as well. In addition to the size range, they offer another advantage - they are about $6.00 for a bag of 50!
Now that I have wheel dimensions, I can cut the axles and front bearing tube to length and get things rolling.
Time - about 2 hours to figure out the first wheel and tire set-up - 20 minutes each to do the rest
Costs: 2 pr BWA wheels @ $6.50/pr, set of Ninco wheels - about $5.00, Ortmann & EJs tires - $10 - axles $1.00 (I buy ground drill blanks in lots of 25 from an industrial supply house)
Looks like it's going to be about a $90-$100 slot car