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Old 07-21-2025 | 12:49 PM
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Artbyrobot
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I finally finished making the tensioner mechanism for the winch in place pulley and I taped it off up the string descending from the ceiling and taped the far end of it onto the ceiling. I noticed I have to keep it as straight as possible since when curling with too much turning the elastic bracelet cord grips the sides of the PTFE tubing which could interfere with the amount of tension it brings to my winch in place pulley. So this will mean on the robot itself it will have to go from the shoulder all the way down the torso in a straight line and then down the leg to about the knee as well. It's 44" long in total. I ended up bumping up the elastic bracelet cord to 30" long to reduce the amount of tension it puts on the winch in place pulley more. The longer it is the less tension it brings and the shorter it is the more tension it brings. If it really can't fit into the leg I can cut the elastic bracelet cord in half and place braided PE fishing line in between the two halves and have that make a 180 degree turn around a pulley and thereby have the same length of elastic bracelet cord but separated into two halves mounted parallel to eachother that create a in series matching tension but taking up half the overall length. This way I could keep it out of the leg area if needed. However I think it might fit into the leg area fine perhaps. Not sure (once we get all the other motors and their tension strings that amount of 2.2mm OD PTFE tubing will start to add up.







Note: I'm also considering taking the elastic bracelet cord out of the tubing and lubing it then putting it back in since lube on the grippy elastic bracelet cord would take away it gripping the sides of the PTFE tubing some I think. Silicone lube is best for this according to chat gpt.



Note: to secure the far end of the elastic bracelet cord I used 401 glue to glue on PE fishing line onto its end the same way as we discussed before and then took the far end of this PE fishing line and came out the end of the PTFE tube with it and taped it off onto the outside of the tube. We'll see how that holds up it might need to be glued down if it gradually is pulled through the tape over time which would be no good.
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