Fw: Help requested with crank-pins for an Arbour Models 4-6-0

Richard White

Steam era freight car discussion group. The time period covered will be from 1900-1960.I bought an Arbour models Sylvania Central 4-6-0 locomotive kit on E-bay a few months ago. It's purpose is to haul my model freight cars (obligatory freight car content).
I am now assembling the kit, which is enjoyable, but have discovered that it has 5 short crank-pins and only one long one, when it should have two long (to accomodate both connecting rods and coupling rods) and four short (which accomodate coupling rods only).
The crankpins screw into a hex-head nut which fits into a moulded cavity in the back of the driving wheel. The outside diameter of the thread is 1.4 mm according to my vernier caliper. I am unfamiliar with US threads, so I don't know what thread has been used on the crankpins. There is a shoulder 2.2 mm in diameter, followed by the bearing area for connecting and coupling rods which is 1.5 mm in diameter. At the outer end, the crank pin steps down to 1.2 mm diameter and a brass cap makes a force fit on this to hold the whole assembly together. The short crank-pins are 6.8 mm long and the long ones are 7.7 mm long overall.
Can any one tell me what make these crankpins are and where I can get spares?
I thank you in advance and apologise for the bandwidth taken. Please respond off-group to rhwhite@botsnet.bw if you can help, otherwise Judge/Sherriff Mike will have something to say to me!
Richard White

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