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ask about band

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
pullDistance / (1 - pre-stretchFactor) / pulleyFactor / (desiredStretchFactor - 1)

So for for example my 82cm invert, which has an effective pull of 82cm in it's current setting, with a 300% stretch and 15% pre-stretch it would be:
pullDistance / (1 - pre-stretchFactor) / pulleyFactor / (desiredStretchFactor - 1) =
82cm / (1 - 0.15) / 2 / (3 - 1) = ~24 cm

Then of course mount the rubbers so that they are pre-stretched at your desired percentage.

Now I don't think precision will matter. After a few uses the rubbers become stretched anyway, messing up your hard work and precise calculation. The most important is the factor-2 of the pulley and that contrary to classic guns you have to take the whole pullDistance in account, not 2/3 of it.

* The above is for a single strand of rubber. For MVD you'd need 6 strands for the factory setup. If you have a gun where one or more of the bands loop around an anchor (Alemanni?), then of course it would be half the bands and twice the lenght for the looping bands.
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