We'll be casting my first concrete countertops soon. We already talked thickness, reinforcement and sealing with manufacturer of concrete mix we will be using (great guys!) so on that part, we feel safe.
As you can see below, plywood has really smooth finish. I'll seal and round edges with silicone. My question is - do I need to spray form with anything? Or can I just clean it and pour concrete? It looks like it is designed to not need any separating agent, but I prefer to ask before I pour.
We'll be using extra smooth mix designed for countertops and small architectural details, if that matters, and designed thickness is 3cm /(1 3/16 inch).