I'm planning to do a machine with similar design, but with concrete instead of epoxy. For the machine bed, a pre-milled plate will be layed on top of the concrete and bolts will hold it inside the concrete. I'm choosing pre-milled because I don't have any spare cnc to mill it afterwards and also not interested in scraping it. My question is what "therminal expansion" is reffered to here? Is it possible for the plate to be distorted AFTER it is layed in on top of the concrete? And i'm not asking about any distortion due to use, or environmental factors, i'm asking just about the process of laying it on top. I know concrete heats up while stiffening, but is that going to distort a 2cm thick steel plate? And if yes, i also don't care it distorts it it 1 measly micrometer or something like that. So what thermal expansion is reffered to here?