Hopoper for O Scale Trains

I wanted to build a hopper so I could... cough, so my son could load his train cars. This is a large model with supports. It is all printed in place. My print is currently on the printer so I will get photos and update this when I have it completed the project and most of the bugs are worked out. This is the second version that I have sent to print so I am hoping that I have most of the issues resolved.

If you do print please attach photos.

Update:
It does work! It takes a while due to the supports. It also takes a while to get all the supports off. The slide works well. We tried it with some fine stone and it slid down the hopper well. My only complaint is I am about 2mm too short for one of his train cars. To be fair it is a high-end tanker car and it is really tall. Every other car and engine we have goes under it well.

In the pictures, I was trying to use up a couple of spools and ended up with two colors. We plan to paint it so it does not matter.