I found this small gap does not matter. My cars and locomotives run fine over
the gaps. I actually enjoy the clicky clack sound that the metal wheels on
the Märklin cars make when going over these small gaps. The only problem I
have experience is if I have a larger gap due to not connecting the track
tight. I found that this larger gap, especially if it is on a curve, can
cause cars and even front trucks on locomotive to jump off the track.
Fortunately, readjusting the track in that spot fixes the problem.
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