The first picture are the second set of castings for the engines The rest is the start of the first engine Castings are coming out softer by far Still have some issues with the sand sticking on cope side
This one of the reasons why I started to melt cast iron, to make steam engines. Please make a video of it running!
Lost some sand on the rim but usable Am I making my runs to big and they are washing it it There are 2 ,3/4 x7/8 cut back to 1/2 that I Just before entry
The step down to 1/2" will add pressure (increase velocity) to the ingate past that point. You can either reduce the runner and sprue size or increase the ingate size to help eliminate washing the ingates out....depressurizing the gating system. I would try to reduce sprue and runner and increase ingate area. Maybe just a little bit is needed to help so use small increments.