Created a blind crank handle to prevent from having to toss them. The rope that was used to draw up the window blind had broken. The knot tied in the string didn’t have tolerance for slippage. It would work a few times before finally ending up in front of the door; rendering the door difficult to open.
After taking measurements a drawing was produced in CAD. It took a few tries to get it just right, but the finished product works well. The knob is free spinning and uses a screw to fasten it to the handle. The crank and handle was printed out and installed into the side of the blind.
The advantage of the rope is gone. All that is left to do is build a gearbox and attach a quiet motor. The crank will do the job until that is complete.