Track gantry systems are notorious for having different
track spacing so that one brand of roller gantry head
does not fit another. Over the years many suppliers
(Mitek, Alpine, Teelok, Robbins, Spida Machinery) would
build a “Custom” roller gantry head that would fit their
competitors track spacing. That is why it is important
when buying used roller gantry heads, to be sure the
wheel spacing fits the track spacing on your existing
system.