Hello Poetry Pals! I bought a Rocky and Bullwinkle machine a couple of months ago and the Nell motor unit was not working so I tried fixing my motor but a previous owner had already already attempted this to no avail. I then bought a replacement motor from Marco for $64. Unfortunately this motor didn’t have enough torque to drive Nell with the original return spring so sometimes Nell moved towards the saw blade and sometimes Nell moved away from it.
In the original design the Data East designers chose to use an AC asynchronous motor that was geared down to 4RPM to drive the log and saw blade. Asynchronous motors (like the kind in your microwave turntable) will run either clockwise or counterclockwise depending on the starting position. This means that about half the time the motor will run the wrong way and put stress on the reduction gears which eventually fail.
I was frustrated with this because the Nell toy is one of the coolest parts of the machine so I decided to design a direct drop in replacement to fix this. My requirements were that the Nell toy unit that would:
1) always run the correct direction
2) reverse at the end of travel (save Nell or “It’s Curtains!”)
3) not run past the end of travel so that no undue stress is put onto the mechanism.
4) not require any rewiring or other complex electronic work, just plug and play!
To use this new system, the old Nell motor is removed and a new one is put in its place using the holes that mounted the old motor. The original gear and pulley are replaced with a new 3D printed version that can be mounted on the shorter shaft of the new motor. A new driver board with all of the onboard electronics is screwed to the bottom of the playfield in place of the original board and plugged into the native driver board plug (no rewiring). Nell needs to be slid to the far end away from the saw blade and you are ready to go!
Design, testing and manufacturing (Eagle design, custom etching, CNC drill pattern etc) has taken a lot of time so I made three boards since I was set up for production. One is in my machine and has been working great for a few weeks and the other two I’m offering up for sale to the first two Pinsiders who reach out to me via a message on Pinside. The cost for the board and 3D printed parts is $80 and I’ll ship via USPS Priority mail which is $8 for the small flat rate box for the continental US, I'm not sure about Hawaii or Alaska (Total of $88).
I've included photos down below of:
-The driver board mounted under the playfield.
-The motor with mount and printed gear/pulley unit.
-The two units that are for sale and ready to ship.
Here is a youtube video of the unit in action! First I show what happens when Nell is not rescued, note that the log moves at exactly the right speed to just reach the saw blade when "It's Curtains!" Second I show a Nell save. In each case the log moves quickly and smoothly back to it's starting point.
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