Animation!

I suspect just about every model railroader, one time or another, has contemplated including some animation on his dream layout.  I did.  Right from the start.

There was to be a copper mine, which would have its ore, go to the stamp mill.  From the stamp mill to the smelter and rolling mills.  And so it went!

Loading the ore.

The mine tipple was the very first structure I built, from an early AHM plastic kit (1967).  I kitbashed two kits together and raised the bin walls to increase the storage capacity.  A removable roof allowed for loading the ore by hand.  Unloading was the challenge.  I tried movable gates made from brass sheets, operated with twin coil switch machines and, later, with 1RPM geared motors. The first action was too fast, the second too slow.  I was ready to give up on animation. 

Work on the layout progressed.  More track and buildings were placed in front of the mine tipple until the tipple was moved out of reach.  But not out of mind.

One day, while walking through the isles of a surplus store, I found a bin full of small sized roller bearings, at 15 Cents apiece.  Can you imagine, a dozen roller bearings for $1.80 ?  I was wondering why each bearing has a groove around the outer race.  But at 15 Cents it was a bargain, groove or no groove!

Standing with a hand full of roller bearing and starring at the tipple, a light went on in my  head.  I remembered the sliding mechanisms the metal working industry uses to shift gears and speeds on their machinery.  A cam action came to mind, not rotary but linear. I doodled up a sketch, and built the thing.  Because of space constraints the installation does not look as neat as my sketch, but it is working  “Slicker than snot”.

Recently I redrew the sketch with AutoCAD and this is how the ideal installation should look!

Brass strips  number 1 and  2, 1/16”x 1”x 6” with two roller bearings each, and strip number 3, 1/16”x 1”x 10”, make up the first assembly.  Strips 1 and 2 have slots for mounting to wood support and fine adjustment.  Strip number 3 has one end bent up at 90 degree and a hole drilled for the push pull rod “B”.  The other end of strip 3 has a slot cut through at an angle with a short length of straight at each end.  The large opening at the end of the slot allows the grooved roller bearing, mounted to rod “A”, to be inserted.

Stops are set on rod “B” to keep the roller bearing from jamming against the end of the slot and bending the rod.

Strip number 4, 1/16” x 1” x  4” with four roller bearings and mounting holes, guides rod  “A”.  The gate at the tipple is a .015” thick strip of brass with a rectangular opening cut through it and soldered to rod “A”.  Pulling or pushing on a knob attached to rod “B” moves the gate with minimum effort.  Control is extremely fine.

The bins hold about 14 ore cars worth of ore (crushed walnut shells).  The walnut shells came from my work place, where they are used for ‘sand blasting’ metal patterns.

That brings us to, unloading the ore at the stamp mill.

Unloading the ore.

HO scale ore cars do not have working drop doors for unloading its load. The only way to unload, is to turn over the car by hand, or vacuum out the load. Eider method is difficult when things are out of reach. On my layout, the mine and the stamp mill are on the branch line.  Both are out of reach.  This forced me to make up an attachment to a vacuum cleaner, which I installed at the delivery track and inside a structure. The roof of the structure lays loosely on top of every thing for easy access to things.

We slowly back the loaded ore train through and under the home made hood, and turn on the little shopvac.  The effect of seeing the pile of ore dropping down looks very realistic.  The illusion of the ore falling down through the gates, is because the eye does not see the fast moving ore being sucked up.

Frequently during open house, we demonstrate this operation  and we earn applause and approval.  But, during a NMRA meet open house, things went terribly wrong!  I have been using the little shopvac for cleanup before the open house, and when I was done cleaning up, I re attached the vacuum hose to the exhaust, instead to the intake port!!!

You guessed it, the instant we flipped the switch one the vacuum, the roof blew off the Structure and ore blew all over the landscape. Not something you want happened at an open house!  Way to frequently  people tell me, how much they enjoyed seeing the disaster.
 

copyright February 21, 2005
by Rolf Plachter all rights reserved.