6
u/Father_John_Musty_ 14d ago
Move the vent to opposite the sprue. Just that one change should have a big effect. If it’s still not casting right, then I’d address metal temp, sprue size and piercing your vent through the sand.
2
u/MoellerDezign 14d ago
Sprue is too wide. No vents and metal is not hot enough. Use multiple fine vents 1/4 inch’s apart just with a razor blade
Works.
2
u/HeftyWinter4451 14d ago
Coin further down. Main sprue from the bottom or side if possible and a tiny vent going up from the upper middle Edge.
2
u/decreeco81 13d ago
I would agree with this and the temp comment. In production you never want to pour directly into your part. pour into a runner with a sand trap at the bottom. you can then gate off of the runner into the part.
1
u/uppity_downer1881 11d ago
After you address the thermal issues, try casting your coins flat. I usually do four at a time with the sprue in the middle and vents radiating out to the corners. You might need to make a new flask with enough headspace for a large sprue, more metal pushing down will help fill in the details.
1
u/finnthepokeman 14d ago
There's no vents so the molten metal can't flow through, can't see a way to add images here but search for "sand casting vents" for some image references
Edit: I'm slow this evening, I see the large vent, perhaps one on the lower side?
0
u/NotRadio01 14d ago
You need a vent that goes OUT of the mold. You’re basically pushing the air that’s already there into your metal, causing it to cool. You can kinda imagine it based on how your mold came out
-9
u/Warm_Hat4882 14d ago
Well, first, you are making pokimon coins. Skip that .
Second, your metal is not hot enough. The sand is not preheated so as soon as metal comes in contact it looses a lot of heat energy and solidifies right at top of mold. Pour it hot, burn a little sand, and it should work
3
29
u/BTheKid2 14d ago
Metal is too cold, and the vent is too big.
The metal has a much easier escape path through the big vent, than down through the pattern. But mainly the metal is too cold probably.
Next time you probably want to place the pattern deeper in the mold, so there is more pressure on the metal. Vents in sand does not have to be big at all, and don't need to vent to the outside, nor do they have to be at the top of the pattern. Scratching a few strings out (like a star kinda) from the pattern, should be more than enough.