I have NE dory, taken it out sailing twice, I have some experience in sailing not anywhere near expert, have it in the ocean bay and the boat does great on a starboard tack, running great, rudder very responsive at close haul starboard, then tack to port close haul, rudder unresponsive, and seems to drift, adjust sails, move rudder nothing, drifting so I let out main still dead rudder, drift reduced. I try this run, or course, a few times the result is the same.
did some research the main cause, maybe an asymmetrical shaped dagger board?
if it is off a little there could be problems my leading edge is about 3mm, trailing edge about the same.
Have you tried the other direction? Establish a good port tack close hauled then go for the tack to starboard? If they are the same result I’d say board asymmetry isn’t the issue. Now the board shape may not be perfect but most of us don’t have templated NACA foils.
The NED rudder is pretty shallow and that affects technique. The Skerry has the pivoting rudder blade but the rudder posts are incline a lot so the rudder not only pivots but tilts so it’s not as efficient as a modern skiff with vertical rudder posts. I think the NED has some of that.
So I find with my skerry I need to be a bit loose, not hard on the wind, and drive thru the eye with as little rudder action as I can get away with. And still I mess it up sometimes. And these are very light boats without much inertia so in choppy water sometimes a wave kills the tack part way thru.
I’ve seen some folks here show a mod to their NED rudder to give it a retractable lower blade to get more effective rudder action.
i noticed in your comment you mentioned running on an ocean bay - is the wind directly aligned with the wave forms - or in other words, when you tack and passing through the eye of the wind, are you perpendicular to the surface wave?
for small boats, as mentioned, there is not a lot of inertia. i used to race dinghys (dyer dhows) in long island sound and the winds and wave forms were typically not aligned…making one tack signifcantly easier - or at least requiring significantly different technique - than the other tack.
i would look to verify that first before things like foils not being symmetrical. the low performance dinghys with flat boards are not so highly tuned, in my experience, that that’s going to make a difference unless the asymetry is manifestly visible.