I have in boxes several different older RC cars/trucks and other stuff taken apart. Most of the gears are white colored & seem to have the same teeth spacing. I also tinker with Lionel trains. I started a project by taking apart 2 modern Lionel 4-4-2 steam engines in order to make either an articulated 4-4-4-2 or a non articulated 4-8-2. The plastic gears spacing on them is the same as most of the RC & toy stuff but the gears are black in color. I think they are still plastic. If I use various sourced gears together is there a chance one gear can destroy another in short time?