Next shot with sand casted aluminum 
The surface of the result got very nice and hand “drawn” air exhaust works very well.
Nice tutorial:
Somebody in our lab could not resist and finished the parts while I was away. It was definitely a good idea to place them propperly. 
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It looks cool but give me more information about it and why did you do it please
Lost pla techniqu perhaps?
@Itzel_Ortuno Look into the linked tutorial obove. The casted part is for russian motorbike.
@lightshadown No, the model is not lost. It’s just sand casted. Check the linked tutorial.
I did an investment casting with PLA to fabricate an intake manifold and air box for my micro car project.
Hollow parts either need cores or need to be invested and burned out. I opted for the latter solution.
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