I finished the pattern making and cast the part last night, it was a bit tricky to make the pattern in a two part flask since the plug had details on both sides.
First I filled the inside of the plug with sand and rammed it in one of the flasks.
Here I have carved out the runner.
After that I filled the second flask entirely with sand and fit the two flasks together, you can see both the sprue and twin vents.
After some careful knocking I could lift the upper flask...
and after even more careful knocking I could remove the pattern from the lower flask.
When I fitted tha flasks back together I had me a completed pattern, now I could start heating up the electric furnace and start preparing for casting!
Since I didn´t have anyone that could take pictures while I was casting we skip forward an hour, here I have just finished pouring the aluminum. You can see that both vents have filled up with metal so it looked promising.
20 minutes later the casting had cooled down enough for me to check it out, very exciting!
The result was very good! Some minor casting beard (swenglish...) on the parting surfaces but it is easily removed. Sweet success!
Here the finished casting lies next to the 3D printed pattern, there are some similarities between the two.
The other side.
Here is a closeup on the cast surface, pretty fascinating that the 0.15mm high 3D printed layers can be so clearly seen in the finished casting.
Right now the part is in the kitchen oven being heat treated at 175°C for 8 hours. The improvement in the metal structure afterwards has proven to be major.
Cheers!
/Anders