This is what I am guessing is roughly the situation you are describing. If it isn't, I cannot imagine the concept is much different.
The slack is a result of the chain's slight ability to stretch, and in this situation is fairly normal, Unless your chain is very loose, even with no loads at all, in which case you should shorten the chain. In the setup pictured that slack can hardly be helped and has likely little effect on the performance.
Another beautiful drawing courtesy of yours truly
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If molecular reactions are deterministic, are all universes identical?
RIP David Shafer: you will be missed
