Doesn't look like anyone here uses the Flex Track.... I'd be curious to know how the width between tracks is controlled as well. Must just be the gravity or force of the wheels on the dolly that spreads them to the proper width. Doesn't sound very reliable but Losmandy make really good stuff so it must work ok.
Here's what I found on the site.
COPY from site: [font=Arial,Helvetica][size=-1]"End Spacers: The End Spacers are primarily used when one has only a single piece of FlexTrak. When the track is looped backed to create the second rail, the looped end often balloons out making the track too wide for the dolly's wheels. The End-Spacer is used to clamp down on the loop to tighten the distance of the two rails to the proper spacing, and thereby create an extra foot or two of travel that would otherwise be lost. The same is true of the other end, where the track ends tend to curl. When using two pieces of FlexTrak, lying parallel to each other, the End Spacers are usually not needed. The 40 foot run is usually long enough that one does not need to worry about possibly losing a foot or two on each end."
maybe that answers our questions....
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