Re: What thickness flax packing to use?
I presume you are talking about a prop shaft stuffing box & not a rudder post stuffing box (not that it matters, both are the same). Measure the dimension between the shaft and the male threads on the stuffing box that the packing nut screws onto. The packing just needs to fit logically up inside the packing nut (between the shaft and the nut). No rocket science here. If the packing came out in powder, the nut may have been overtightened. Remember, on a traditional prop shaft stuffing box you absolutely need have moisture, & maybe a drop of water every 30 seconds or so coming from the stuffing box to lubricate and cool the packing. Rudders aren't so critical as they aren't spinning & heating up.
