Lionel Coal Car Dump Sled

thingiverse

My father bought a Lionel coal dump car off eBay, but it arrived broken. Instead of buying another or returning it, he asked me to fix it using my 3D printer. The coal car dumps its contents when triggered by the engineer due to its spring-loaded mechanism. A plunger holds the hopper in place and is pulled out by an electromagnet on the track. Once the plunger moves down, the spring pushes the hopper up, which pivots on a hinge. However, one of the pins holding this hinge was damaged, causing the hopper to move off-center when released. I used my calipers to replicate the broken piece in Fusion 360. After making adjustments to get the pin sizes, hole diameters, and plunger distance right, I created a functional replacement part. The original broken piece is on the right, while the new one is on the left. I've included the raw STL file from Fusion 360 as well as one that's scaled to 100% of the real part and rotated for optimal printing results.