Well, this was interesting. As I prepare my foam for the compound wash I needed to get a couple styrofoam cups. No-one carried them. I went to , Wal-mart, Giant Tiger, Canadian Tire, Zhers, Dollarama and not one of them carried it. My last try was an independent dollar store and found these crafters cones. They came in different sizes and gabbed these. I will cut the small end to match the spout and hollow them out somewhat. Necessity is the mother of invention, Eh?! LOL Crazy crazy.
Here's an idea that I don't think I've ever seen on this forum. I've see youtube videos made by companies that make hollow paper runner systems for lost foam casting and that made me think, would hollow paper mache pouring cups work?
A soup can with both ends cut off and stuck into the sand around the sprue is probably about as good of a pouring cup as a foam cup would be... Jeff
Using a solid foam form for the cup does not work very well. You need to use a self-supporting cup because the sand will not stay in place once the foam cup is evaporated. The reason for this is because the sand near the surface of the mold is not well packed and has no weight of sand of above it to help hold it in place, and you can't keep the cup completely full so the metal pressure (which is almost nothing at that depth) can't keep the sand in place like it does deeper in the mold. So the cup typically collapses while you are pouring. Also when you pour the metal on that big blob of foam, it will melt in a very disorganized fashion, creating a lot of fuel that floats, ignites, and creates a lot of flame, black smoke, and turbulence in what's left of the pouring cup......which is very bad. Thus, use of a tin can is much better. I actually recommend using a square/rectangle can as the cup, leave the bottom in it, and cut a hole at one end the size of the sprue. You then fill the mold to the top of the sprue (as shown below), place the cup over the sprue, and fill the mold the rest of the way to bury the sides of the cup. Round cups tend to aspirate air due to Coriolis affect. Square cups do not. Leaving the bottom in the cup prevents sand erosion on the floor from the pouring stream, especially around the sprue, but an open bottom can or bent form work too. Immediately after the pour, just remove and empty the cup with a pair of pliers while the metal is still molten so it can be reused. Best, Kelly
Thank you so much for the added information, so much new education. I hope to pour later today. I see you've added a small damn to control flow as well. I'll post my progress. Thanks again Kelly.
