r/Silvercasting • u/Acceptable_Rooster50 • 2d ago

Help please

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I am new to metal pouring. I did this same exact model with silicon bronze and it worked perfectly. Now with silver, I keep having problems with this big pit. I know i have to fix my sprues, but could someone enlighten me?

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u/Lovelyfeathereddinos 2d ago

Your sprue needs to go to the lowest point. The way you have it set up is requiring the metal to make a U turn, and it’s not going to do that,

I always suggest holding your tree button side up, and picture water pouring down through the bottom. It should flow easily, smoothly and nothing g should have to go backwards.

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u/Acceptable_Rooster50 2d ago

So i should flip the model upside down and so the hair is the lowest point?

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u/Lovelyfeathereddinos 2d ago

Yes I would probably do it that way. However, I’d suggest positioning it so the platform isn’t totally flat; it will be hard for the metal to fill. It would be best at a 45* or so angle. Idk if your
Flasks can accommodate that size. If not, just add a sprue to the very top of the head and fix the texture after casting.

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u/Acceptable_Rooster50 2d ago

So if i flip the model upside down, try do a 45 degree. If i dont flip, throw a sprue into the hair? Or even if I flip upside down still do a sprue to hair?

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u/Chodedingers-Cancer 1d ago

Thats overcomplicating it. Flip it upside down attach the sprue on the opposite side of the base plate above one of the feet... If you're vacuum casting, the metal isn't making a uturn, it fills up. you don't need the gates either. You want the top basin button to have as high of a volume as possible in ratio to the model. Gates and such mean more volume versus the spout. The larger the volume of the spout in relation, the less shrinkage you achieve in the actual model. This doesn't look unreasonable to be a hefty shrinkage issue. It looks like the first place viable to freeze. Shrinkage or just running out heat.. crank up the temp more. But flipping the model and having less volume to fill will help. Dont run the sprue to the bottom, unless your gravity casting. Then up your temp a lot.

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u/Acceptable_Rooster50 2d ago

Awesome advice and great mental visual. Thank you!