Railway Ballast Cleaning Train - Part 5

Now it is beginning to look like something interesting albeit bizarre! 

The long sloping down arm is the excavator in its 'parked' position. There is another one on the other side. These were lowered and pulled out to the ballast shoulder. First though the ballast must be cleared manually (I assume) from between two sleepers down to the substrate because the two excavators are joined at their base by a removable section that goes under the rails. Contained in the arms is a continuous chain driven series of blades that collect and push the ballast to and up the furthest arm as the vehicle moves slowly along the track. I'll explain later how that was done as the machine is not self powered. At the apex of the arms the ballast falls onto a conveyor (the sloping up piece) that moves it to the sieve (not yet modelled).

I am pleased how well the 3D printer created the chain driven blades. I designed these as separate components with their blades attached to a thin wall (the chain), the flexibility of which allowed it to be bent around the curve at the base of the excavator arms.

The  excavator 'motor' is positioned high up and pokes above the girder frame. Understanding its shape and fixings was extremely difficult to glean from photographs as it is not clearly detailed but, eventually I got the drift and whilst not totally correct to prototype (there is a mass of girders etc. up there that are not modelled) it looks ok and gives the impression it could work. 

The conveyor belt came at well. The printer decided to give it a slight ripple in places that gives the impression of a floating, flexible belt. Colouring of this was done with black pastel scrapes.

This was an intense design period so, I'll return to the simpler Power Generator wagon next for a mental break.

In fact, there are another two more intense design periods for the ballast cleaning wagon before it is done. These being the sieve mechanics and spoil expulsion.

To Part 6

To Part 1.