I was looking for different molding sand recipes and I found one that I wanted to try out. The molding sand consists from cement and synthetic engine oil (other oils might work to). For 10 kg cement I used 1.3l oil.
The surface finish on the casting from the cement was smoother and it didn't have pitting on the surface.
What I didn't like was the molding process was trickier and it produced nasty smoke. I don’t see using it that often, not until I have a fume hood.

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By The Croft by Joakim Karud   / joakimkarud  
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