A date in this context is a time when you meet up with a potential romantic or sexual partner with the intention of having fun together doing some sort of activity.
So first or second time you meet them you should tell them of your intentions as far as commitment is concerned, some might even say before you meet up at all. And definitely before any kind of sex.
As for conflicts between what you say and how you act, that can be tricky for some people, but I would say that you should address that specifically by saying something like “I do tend to act in a way that a lot of people would interpret as long term commitment energy, but I need to be clear that this is just how I behave in relationships, and it doesn’t mean that I plan to stick around. I still am only interested in short term commitments at this time and only if I explicitly tell you otherwise should you think anything else”.
Just say what you think and feel and do so upfront and multiple times. Be open and honest and allow them to make their own decisions without guilting or pressuring them.
I think you could do this with a pull cut plane after you cut to close to the correct thickness with a hand saw. A pull cut plane will prevent the thin sheet from buckling as you try to thickness it, just have to get clever about anchoring it. You could glue a board to the back and then hook it on a table using that board, plane it until you’re satisfied, then cut the board off.