January 7
Spiking continues - I'll finish the Lower Clear Creek Siding sometime next week and start the transition to the Randolph Mill and Chamberlain Works. Planning on adding the bench work augmentation that Lower Blackhawk Yard requires and finish the roadbed work there next week as well.
Over the holidays, I ran across a small "relaxation fountain" that sells for $5 at a local drugstore - this is a 3V motorized pump that circulates water through a rock sculpture to create soothing sounds. The pump can run on both battery or 3V from a DC converter, so I've picked one up because I see it as the driving guts for the operational diorama for the Randolph Mill - pump the water through a trough that both powers a waterwheel that drives the stamps and run the water under the stamps and over the amalgam table. ll have more as I work out the details, but I now can see how to actually make the Randolph cutaway "do" something prototypical.
OTOH, engine building is pretty much back to square one. My original design can be assembled (I have a quartered pair of drivers with side rods added) but it lacks the operational stability I'm looking for. The central problem is that the wheel bosses don't have enough surface area to form a strong bond between them and either the axle or the Delrin spoked wheels. So, as you rotate the drivers, the bosses give at pretty much the first binding point. Obviously a better solution is a single cast driver and this leads me to my PSC questions. I've found some 36" cast drivers in brass or plastic, but before I order, I'm wondering if folks can help with the following questions:
- Are the plastic drivers stable enough for an operational engine? - I've ordered plastic from PSC before and "flimsy" doesn't begin to describe the quality of what I got. If the plastic is stable enough, what have folks used as crank pins to avoid reaming out the mounting hole?
- If I go with brass, am I better off isolating the center from the tire or isolating the center from the brass axle? And what do folks use for this?
I'm also looking at gearing all the axles and having the side rods just be for "show", but I figure I can first replace the driver centers and try that before I completely trash my original design.
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