I know everything ... but have a rudder question.

[BOAT]

I do not know much about the X rudders and I have never had an issue with rounding up in wind even over 30 knots In my case the boat just seems to lay on it's side and continue forward - I can tell your that the proportion of rudder that is under the boat on the M makes a difference. The way I adjust the rudders is by turning the screw all the way IN on the rudder adjustment on the port side rudder and all the way OUT on the starboard rudder. Then i sail a port tack, then a starboard and get a feel for which rudder is getting the best performance based on the drag on the wheel and the speed of the turns. Every time I have done this I seem to get the best performance (speed) with the rudder that is as far under the boat as I can get it. But I seem to get the best helm response from the rudder that is more behind the boat than under it.

Go figure.

One time my rudder managed to slip past the adjusting screw altogether and was all the way under the boat against the bracket and I learned that day that if the rudders are TOO far under the boat they tend to make the helm a little bit squirrely.

I don't know if that helps but that's about all I have learned about the M rudders.

[sailboatmike]

I can tell your that the proportion of rudder that is under the boat on the M makes a difference.

Very true Boat, this shortens the distance between the keel and the rudder and in effect in car terms shortens the wheels base. The M Rudders are
considerably further forward than the X's which just hang with the leading edge a couple of inches behind the transom

The way I adjust the rudders is by turning the screw all the way IN on the rudder adjustment on the port side rudder and all the way OUT

You have adjustment screws on your rudder brackets??? Can you post a picture, very interesting

One time my rudder managed to slip past the adjusting screw altogether and was all the way under the boat against the bracket and I learned that day that if the rudders are TOO far under the boat they tend to make the helm a little bit squirrely.

This is exactly the syndrome cars and bikes suffer when the wheelbase is shortened too far, add to this the very direct nature of the Mac steering and it can become a hand full, I know on my X lock to lock is less than one turn of the wheel. Compare this to other boats with wheel steering and Its way more direct, I think this is a hang over from trying to make too much like a power boat.

[BOAT]

Yeah, all the M boats have a rudder adjustment for the rake on the rudders.

The idea of the rake is not really to "shorten the wheelbase" so to speak but the purpose is to get the rudder balanced in regards to how much of the rudder is in front of the pivot or how much is behind. It's not somthing I can explain well because I am not well educated in those things but a pilot like Hamin'X or an engineer like Tomfoolery would be able to explain it much better.

All I can say is that a balanced rudder was a very critical thing in most modern sailboats that had a big rudder that was under the boat. If the rudder was really big you needed a little bit of it to be in front of the rudder shaft to help you turn the rudder. I never thought a balance on the rudder would be important for such skinny ones like the ones on the MAC hybrids but for some reason when Roger did the rudders on the M boat he has about 10% (?) of the rudder in front of the rudder post. That's a balanced rudder.

He also added the screws to help adjust the balance. On a boat so cheap you gotta wonder why Roger would spend the extra money to put adjusters on the rudders - well, I sort of figured out why when one of my rudders slipped too far forward - I discovered that the balance makes a difference.

We really need Tom or HaminX to post here and explain it. I really can't describe it well like they can.

[NiceAft]

We have rudder adjustments Whoa

Right after I finish my icecream, I’m checking this out. I might have to change the boats name from Nice Aft to Nicer Aft.

Ray

[BOAT]

Yeah, here is a picture of it from the BWY website (I am too lazy to get off my butt and go to the side of the house to get you a picture from 'boat').



And there is the other part where a tab is welded on the rudder bracket where the bolt rests on the other side. I mean REALLY!?? can you imagine? The hardware might only be an extra 14 bucks for Roger to cost when he does this but THE LABOR?? The LABOR to weld on the extra tab, drill the holes, install the hardware, blah blah blah? on the factory line that's another 15 minutes and design costs so he needs to jack at least 100 bucks in the cost to cover that - ANY time a factory puts a hole in any part of a boat you gotta say WTF? (Why This Fitting?). No one drills a hole in the boat without a reason.

It was one of those little things that just seemed out of place on such a cheap boat to me when I saw it - "What was he thinking??"

Then one day I started playing with these little things and then I was said "Oh, so THAT'S what this thing does!"

I'm glad I have it after I have it.

[sailboatmike]

Yeah, all the M boats have a rudder adjustment for the rake on the rudders.

The idea of the rake is not really to "shorten the wheelbase" so to speak but the purpose is to get the rudder balanced in regards to how much of the rudder is in front of the pivot or how much is behind. It's not somthing I can explain well because I am not well educated in those things but a pilot like Hamin'X or an engineer like Tomfoolery would be able to explain it much better.

By bring the rudder further forward (having more under the boat) it is in effect shortening the wheelbase as the boat turns around keel. On a boat even small adjustments can make a marked difference, however as you noted if you take it to far the boat will become a bit squirrely eg. small rudder inputs have greater effect. This effect can be seen and felt if you ever drive a forklift (Most also steer from the rear like a boat) which has a short wheelbase.

Check page 17 on the M owner manual, it has pictures of the assembly but does not really describe what it does http://www.macgregorsailors.com/manuals ... l_2003.pdf

[BOAT]

Yeah Mike, that's all true but like I said, I don't think that's what the rake adjustment is all about. I'm pretty sure it's there to adjust the percentage of the rudder that is in front of the rudder post. I think the adjustment is just to balance the rudder so the helm is responsive but not too hard to hold course - like I said - we really need someone else to explain it - I did find the SOP on this thing in the original specs that came with the boat from Roger:




If the rudder
blades angle back, the rudder area moves aft of the pivot point,
and the loads on the steering system increase dramatically. It is
also possible to have the rudders too far forward. If the center of
pressure is ahead of the pivot point, the steering wheel will pull to
the right or left (much like a steering wheel on a car behaves when
you are backing up). Adjust the rudders to the position where
there are only small loads on the steering wheel.
There is a small adjustment screw on the leading edge of each rudder
fitting. Turn the screw to adjust the fore and aft angle of the
rudder blades.
If steering loads are heavy, first make sure that the rudder blades
are really pulled down tight against their stops. If the blades stick
out from the rear of the boat, steering will really be difficult.
After you are sure the blades are fully down, turn the screw clockwise
to cause the rudder to angle forward. Adjust it so that there
is very little load on the steering wheel. When underway, pull
hard on the rudder line to once again make sure that the blades are
down and against their stops.
If the rudders are angled too far to the rear, and there is too much
pressure on the rudders, you can damage the steering system.
If the steering cable system becomes inoperative, you can remove

[BOAT]

Hey Mike, I guess I was posting the owners manual at the same time you were.

Maybe Tom will chime in and explain this thing to us.

[Jimmyt]

I'm waiting for one of you to explain how turning the screw clockwise moves the rudder forward...

Is it a left hand thread? I'll go downstairs and check after Ray finishes his ice cream...

Anyway, the more blade you have ahead of the rudder post, the lighter the steering effort. Until, you get enough blade ahead of the post where it starts to "self-steer". Sort of analogous to the caster/camber adjustment on your road vehicle.

[BOAT]

I'm waiting for one of you to explain how turning the screw clockwise moves the rudder forward...

Is it a left hand thread? I'll go downstairs and check after Ray finishes his ice cream...

Anyway, the more blade you have ahead of the rudder post, the lighter the steering effort. Until, you get enough blade ahead of the post where it starts to "self-steer". Sort of analogous to the caster/camber adjustment on your road vehicle.

Yeah, I guess that's what happened when my rudder slipped past the adjustment stop - I noticed one rudder that seemed a little too far under the boat one day while i was underway and when i was tacking that side hard over the boat seemed a little bit squirrly - not bad, but just not as solid as usual. I raised the rudder and re set it so the bolt was hitting the stop and the squirellyness went away.

I am getting the best helm response with the bolt backed out as far as you can possibly go without losing the lock nut. I have never had a problem with rounding up - ever - so I must say the rudders on my boat work pretty good.

[Jimmyt]

Thanks for sharing that info. My adjusters are screwed all the way in, such that my rudders are as far angled aft as possible.

Next time I'm in the water I'd like to test a little bit of a forward lean. The photo in the manual shows the hardware arranged differently than mine (no surprise). In fact, even the two pics in the manual are different. One jam nut in one pic and two in the other. Based on the written instructions, the bolt head should be resting on the stop instead of the threaded end. It would be less likely to go past the stop or bugger the threads if it was reversed also.

Maybe I can back the trailer up to a ditch and do some rudder adjusting. We're having terrible weather right now. Heavy rain and thunderstorms every day. The bay will be too murky to see to adjust in the water, plus I'm prone to drop tools while working.

[dlandersson]

When I want to swap out or play with my prop, I have a cheapo inflatable dinghy that I tie off on the rear of my X and I just do the work in the marina.

Thanks for sharing that info. My adjusters are screwed all the way in, such that my rudders are as far angled aft as possible.

Next time I'm in the water I'd like to test a little bit of a forward lean. The photo in the manual shows the hardware arranged differently than mine (no surprise). In fact, even the two pics in the manual are different. One jam nut in one pic and two in the other. Based on the written instructions, the bolt head should be resting on the stop instead of the threaded end. It would be less likely to go past the stop or bugger the threads if it was reversed also.

Maybe I can back the trailer up to a ditch and do some rudder adjusting. We're having terrible weather right now. Heavy rain and thunderstorms every day. The bay will be too murky to see to adjust in the water, plus I'm prone to drop tools while working.

[Jimmyt]

Roger that.

What I'm thinking is, I need to get the rudders fully down so I can align them with the rudder posts to try and get the angle right. Not sure I can pull that off with it in the water. Could do trial and error repetition, but who has time for that if the wind is blowing? Sailing bad is still sailing...

[Highlander]

I believe Rudder craft also makes the Bigger Plastic IDA Sailor Racing Rudders out of fiberglass now resolving the breakage Issue !
I remember seeing that at one time need tocheck & see if they r still making them !

J

[sailboatmike]

After reading a few posts about breaking rudders and they always seem to break in the same place which I presume would be around the area that the rudder goes into the bracket (the point of greatest stress) I checked the rudders on my dinghies, they are all made from tin plywood, HOWEVER they all have a thing Aluminium or Stainless steel plate on each side (around 1/32" or 1mm) to help reinforce that area, it normally runs from the top to almost the waterline.