what de best way to align rudders? (low tech and simple please) thanks

Tape Measure. Measure leading edge, measure trailing edge. Or are you looking for alignment on a different plane/axis?

tanx men, a little more detail on the exact procedure, remember i aint so smat...

Most folks will make a small mark on the leading edges of each rudder about an inch below the transom. Make a matching mark on the trailing edges at the same height. Measure the distance between the leading edge marks and the trailing edge marks. If they are the same, your rudders are square. If the leading edges are closer together than the trailing edges, you have toe-in. Most folks further confirm this by making additional marks on the leading and trailing edges of the rudders very near the bottom and repeating the measurement. Classes sometimes have slightly different tuning recommendations on rudder alignment.

BUT...first you have to elevate the back of the boat enough to put the rudders down into their normal sailing possition. Usually you can do this while the boat is on the trailer, but depending on how deep your rudders are, maybe not. If I lower my trailer hitch to the ground and use a slight slope, I can just barely get my rudders all the way down and not hit the ground.

If you don't have a slope available, try lifting up the back of your boat off the trailer by putting life jackets (or something else) under the hulls where they contact the rear trailer supports, or maybe you can roll your trailer tires up onto a board to get it up off the ground.

Anyway, you must put the rudders all the way down while the boat is on dry ground, so you can do the measurements described above, unless you want to do it underwater...

Stand behind the boat with both rudders up.

Eye through, from behind, and line one blade up with tip of bow - other one should point at other bow tip.

This is more accurate than you would think.

I wouldn't recommend the "eyeballing it" due to the fact that the rudder geometry changes when the blades are lowered and locked down.

Not if the rudder pintles are in-line with the hull axis...this is actually how I align the rudders on the 20 because it is practically impossible to determine "horizontal" to put a measurement line on them. Horizontal would be the line that the water flows when the boat is sailing...the bottom has rocker and the decks sloped...what horizontal line do you pick?

My a-cat however, has canted hulls but apparently the rudders are mounted on a slightly different axis - they toe WAY out when raised compared to down.

What if there are imperfections in the castings?

Hey Guys,

Do you check the rudder alignment again with the boat "loaded" up??? I recheck the alignment with the sails up and the mainsheet sheeted in as if on a windward beat. Some boats are not as torsional stiff as others ... a H16 for example, this is why I think the H16 sailors "tack" their rudders. I generally do not tack my rudders on my P19MX ... but sometimes I do tack my rudders on my TheMightyHobie18 (depends more on if the rudder cams are working correctly), but as there is no difference in the measurements of my TheMightyHobie18 as a "loaded" boat vs a "unloaded" boat and my rudders are prepped to 2500 wet/dry and polished, the resistance in the water is minimal, compared to me making poor decisions/judgements on which way to go.

If I saw a signifigant difference in the "unloaded" vs "loaded" measurements I would take a hard look at my boat's "stiffness" and make the required repairs to stiffen the boat up ...

Harry Murphey