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October 19 My SP Snowplow

I've been working on my rotary snowplow.  The front truck was held in place with a 2.5 mm shaft without a keeper and every time I picked it up the trucks were left on my bench top.  After a couple of days of that it upset me to no end. This morning I decided to put an end to that problem.  I drilled a 1/16" hole through the chassis/shaft and tapped it for a 2 mm screw.  It came out exactly in the center of the shaft and it's like it came from Athearn that way.

Next I decided to try to power the blade just for kicks.  I dug through my motor collection and found a gearmotor that Motorman sent me to experiment with.  It fits like a glove!  I put an NWSL U-joint cap on the shaft from the blade and one on the gearmotor shaft and the alignment is better than it could have been designed by an engineer at the Athearn factory.  I used my old standby "Goop" to glue the gearmotor in place.  The gearmotor turns the blade about 100 RPM at 2 volts.  I used a 180Ω resistor in series with the gearmotor and at 12 volts it's about 150 RPM.  The current draw is only 40 ma at 2 volts so I can use an accessory output from a DCC decoder in the Snail to turn it on and off.  I'll play around with the resistor value when I get it hooked up to a DCC decoder to turn the blade somewhere between 150 to 200 RPM.  I used three pin Dean's connectors for the interconnect between the Plow & the Snail.

This has turned out to be a real fun project.  I decided to add a crew to pilot my snow machine. By not painting the back of the LED headlight the it should illuminate the crew just enough so they can be seen through the windows.  I'm going to use a crew from a Proto E-9, they are in exact alignment for the windows on the snowplow.  The double A unit of E-9s only needs one crew in the front engine anyway.

I ended up using the 180Ω two watt resistor in series with motor and a 100µf capacitor paralleling the resistor to help the 12 volt motor start reliably at 2 volts. 

It's hard to tell but the snow blade is turning about 150 RPM, the flash stopped it.  Everything is working great.  The LED headlight is so bright even with the current reduced to 3 ma that it's hard to see the engineers in the cab.

The Snail is a Athearn F Series B unit.

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