Hey guys I am working on getting my homemade freehand dialed in and some far am only having luck with the wind forward of the beam… works a charm but who wants to sail up wind all the time…
I am have trouble getting the tiller pilot to operate the trim tab well, problems calibrating the tiller pilot because of my off center out board (and the need to turn in a circle in the direction she doesn’t like to turn under power)… and possibly problems with the compass because my tiller and rudder head are stainless steel, as is my trim tab shaft and tiller arm…
I have experimented with moving the line clutch along the tiller arm but am still finding it frusturating…
my questions are as follows…
What is the length of the tiller arm on the trim tab?
How far forward of the trim tab axis is the neutral point for the line clutch?
Where with respect to the neutral point do I want the line clutch? how far forward or aft? is it different for the Airvane v.s. the tiller pilot? Does it want to change with the point of sail?
(I understand forward of N introduces negative feed back, Aft positive feed back, I assume I want it slightly aft of neutral?)
Appreciate any insight!
Benjamin
Crackertail - Allied seawind 30
West Palm Beach Florida
thank you captain obvious, I am well aware of that fact. I am trying to make sure I got my geometry correct. I have been pouring over lechter’s self steering for sailing craft and have run some numbers for a 10 degree wind shift… the tab angle depends on the location on the tab tiller of the line clutch, closer to the tab axis with result in a greater tab angle… my tab is very powerful, maybe too powerful, maybe too far aft of the rudder but as close as I can tell tab angle is roughly equal to rudder angle… so for a 10 degree wind shift, as mine is currently set up, with the clutch on neutral, would produce a tab angle of 15 degrees, and a corresponding rudder correction of 15 degrees.
is tab 100% power as designed on the free hand, i.e. does a 15 degree tab angle make a 15 degree rudder angle. or does a 15 degree tab angle make a 10 degree rudder angle?
I would appreciate if someone could take the time to give me the simple measurements I asked for in the original post. the most important being:
as designed, how far is the neutral point on the tab tiller from the tab axis? 4"? 5"? please be percise
how far fore or aft of the neutral point do you set the line clutch when sailing, does it change for different points of sail???
Wow indeed! I completely agree with you, Dioscouri. Courtesy, respect and collegiality are watchwords of this Forum in my experience. So perhaps Pressuredrop would like to apologize and rephrase his query?
im sorry for my attitude, which is a result of my impatience… and I forget not every forum is like sailing anarchy…
I am still looking for someone to forgive me and provide me with measurements asked for in previous posts, I know I am close on this thing, and I may just be using the line clutch too far forward on the tab tiller… I am going to mark the neutral point and do some more testing, but those basic measurements would help me check my geometry…
patiently awaiting a reply, gary on shanti you out there??
My current distance on tab tiller arm to N point is 5 inches…
I suspect I am a little short here? vane drum diameter is 15.5" so a 7.75" N point on the tiller would make the tab angle equal to the error angle… at a shorter N point a smaller wind shift would produce a greater tab angle…
looking forward to some hard numbers at some point