@Green Amphibian - I just bought some of this http://www.amazon.com/Starrett-Polis...714&sr=8-3 polished drill bit stock tool steel. Do you think that would still need to be hardened?

@shambrick - don't worry about hijacking the thread, I appreciate your help!. When I first got the tank and tore it apart, I found that most of the fasteners where loose. My wheel screws came loose after I had already tightened them, which is why I think I need thread lock. When screwed into plastic they are very tight and loosening is not an issue. Thanks for the tip about the hex heads suspension arm screws in the plastic tank. Do you know if the thread is the same as in the metal tank?

I wish I had got the $399 sale price. I paid the $499 "sale" price. I will admit that the tank was pretty much an impulse buy. Really I was more interested in the metal hull/wheels set as I wanted to build a high-powered tank. Then I thought, what the heck, it's $200 more, and while $500 is more than I would want to spend on a tank, its still only half the cost of a Tamiya and less than a quarter the cost of an aero-mate http://www.aero-mate.com/Tiger1.htm (although the comparison is unfare I suppose.)

If I can get the gearbox problem squared-away I think I'll be happy, for the moment anyway.