I think I read when pouring flat flask with long pattern it helps some if the flask is tilted a bit length ways. Should it be up from sprue or down ? If so how much ? Flask is 3 1/2 x 12 1/2, pattern is 9 1/2. It will have a vent opposite end from sprue. Thanks, John
Here is a recent thread on this. http://forums.thehomefoundry.org/index.php?threads/changing-gating-for-a-more-organized-fill.2161/ You want to tilt with the sprue down. Otherwise you'd have blobs of molten metal running away from the gate, they would each have low mass and high surface area=cool rapidly. They would hit the other end of the mold randomly and then once accumulated try to coalesce. Because of the cooling they might or might not do so. Sprue down results in a rising cohesive pool of molten metal=good. It does not take a lot of incline. Try pouring a little molten metal on the flat top of a mold. Like quicksilver it will find the slope and flow downhill rapidly even with slight incline. This tilt method is especially important when metal could choose a variety of paths to take. Consider a trivet poured flat. There would be a bunch of paths equally accessible. The one(s) with the least resistance fill for a while until some others are momentarily of lower resistance and so on. The problem is that once the metal pauses for even a few seconds it has a chance to cool and thicken and then block further filling of that path. The end result is incomplete filling. But poured inclined the metal is "forced" to advance steadily and uniformly along all the paths since gravity quickly overcomes channel size as a determinant of resistance. Denis
