banjoflyer posted:mike g. posted:Hi Mark, how did you figure out the amount of counter weight?
Hi Mike, I just noticed I had not seen this question. Since your bridge is tethered at one end by means of a hinge (I'm guessing) I would start with 1/2 of the bridges weight as a beginning point for a counterweight. A small pulley on either side of the hinged end of the bridge would allow weighted cables attached to the mid-point of the bridge to slow the bridges descent.
Kinda like this:
Mark
Shouldn't the cables need to pass through a pulley that would be above where you have it shown on your sketch ?