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weather helm/lee helm

Posted: Thu Oct 04, 2012 10:06 am
by blee
I bought 2007 M a few month ago. Standard hank on jib, standard main. I updated the boat by installing head, holding tank, air condition ( a must in Georgia) full A/C and D/C, plumbing for running water, etc... Mac is the best comprimise. What a boat!! Now I feel like this boat has everthing.

I started to enjoy sailing a lot. I had a couple of good sailing this summer and start to find out the characteristics of the boat. I wonder that the characters I found so far are common to "M"

It seems the boat lacks the weather helm in beating. So I raked the master maximum aft as far as the stock forstay allows. I seems there a very slight or no weather helm on port tack and slight lee helm on star board tack at 10 -15 miles wind 10 degree heeling.

Even at stronger wind, the boat does not have increasing weather helm at either side tack. I understand safe sailboat suppose to show increasing weather helm when she heels at moderate wind but it seems My "M" does not have this tendency at all. Helm stay pretty much neutral or slight lee helm at more than 15 degree heeling. I know the hull shape is different than most of deep keel sailboat but Is this common tendency in "M" ??

Of course, I disconnected engine steering, checked jip and main shape, position, twist, telltale, full down daggerboard (to send CLR forward possible), fore aft weight (pretty much stock "M"), side to side weight distribution (one or two average person at Windward side for tacking) mast (raked maximum backward to send CE backward)

Otherwise, this is an excellent boat, I enjoyed 6.2 miles which is almost hull speed at close reach without any problem last week.

My guess is.. because :macm: has very strong roll yaw coupling. I noticed if i heel the boat portside by adding weight portside she heels and turn port well, add weight starboard, heel and turn starboard. But in a beating the turning ( yawing) force induced by heeling effectively compensate or overpower any weatherhelm tendency induced by CL and CLR.

Has anybody noticed this ??


Is weak weather helm a common character of :macm: ??

Re: weather helm/lee helm

Posted: Thu Oct 04, 2012 7:03 pm
by delevi
Blee,

What you describe is not common at all. These boats are prone to strong weather helm and I never experienced or heard of anyone else experience any lee helm. Make sure your daggerboard is all the way down. It might be getting stuck. Take a tape measure down the daggerboard trunk. It should be 57 inches from the top of the board to deck level. If that checks out, try sheeting your sails tighter and see what happens. At 15 knots of wind sailing close hauled, you should have plenty of weather helm.

Leon

Re: weather helm/lee helm

Posted: Thu Oct 04, 2012 8:44 pm
by blee
Thanks for the reply

First time i noticed this, I thought this is due to daggerboard not fully down so I checked that.
Then I thought the engine weight pulling the steering so I disconnected it.
Then I thought the main is not tight or not getting enough power so i checked halyard tension and outhaul then chamber. It seems ok to me.

so I start searching here and found :

http://www.macgregorsailors.com/forum/v ... =7&t=19401

as i could not find definite answer so I thought i may have slight leehelm in weak wind is common for :macm:

but it seems helm is about same at stronger wind.

I did not check the rudder in detail yet (in the slip) but I cannot reason rudder would cause leehelm.

any other probable cause??

Re: weather helm/lee helm

Posted: Thu Oct 04, 2012 9:46 pm
by seahouse
Very strange. Do I understand from your post that this is not happening at all points of sail, just when beating? Even stranger. For me, beating is the most fun point of sail, particularly in high winds.

The usual problem (with Macs and others) is too much weather helm, and most efforts are directed at minimizing, not reversing it. I assume the top shrouds have been properly retensioned to take up the slack from the increased rake of the mast?

Sheet in as Leon suggests, and move the traveler to windward.

More heel should result in more weather helm. The hull shape (along with other factors) reinforces this.

Check the alignment of the rudders, they should be parallel, and be at the same vertical angle and all the way down.

Maybe too much mast bend is making the mainsail too flat (?)

Is it possible that a previous owner might have moved the mounting brackets at the mast base (and thus the entire mast) forward?

Re: weather helm/lee helm

Posted: Thu Oct 04, 2012 9:53 pm
by seahouse
Sorry for the redundancies there, blee. We posted 2 minutes apart, while I was writing. :cry:

Re: weather helm/lee helm

Posted: Fri Oct 05, 2012 7:00 am
by blee
Thanks for the inputs

1) Yes top shrouds have been retensioned after raking the mast

2) Of course i tried travelers to windward to power the main

3) I have to check if the rudder is vertical instead of leaned to forward too much ( I cannot do it accurately for now as the boat is slipped,but i will try) and rudder alignment ( I too suspect these might be the cause)

4) No mast bend observed

5) I will check the distace between the mast raising hole to to tip of front edge of rubber rail (156") per manual to check the location of the mast bottom

6) I will move the jib sheet block back equally both side to check the jib is not blown out

7) I will have to double check daggerboard 57" as rudder and daggerboard are taken off for barrier paint this summer and reeinstalled by the painter
I checked the 57" at the daggerboard line previously but this time I will insert the ruler to confirm if it is all the way down

Again, currently the helm is almost too perfectly balanced and steer ok. I just do not have positive weatherhelm on starboard tack and on both upto 15-20 degree heel. I never tried beyond that prolonged time and I doubt I will stay long beyond that angle in future. But I want to make this almost perfect boat to me even greater.

Thanks

Re: weather helm/lee helm

Posted: Sun Oct 07, 2012 1:35 am
by delevi
15-20 degree heel is actually the sweet spot. Over 20 degrees you should feel the boat pull to weather. I don't quite understand your rig setup with forestay loose as possible and no mast pre-bend. Sounds like your shroud tension may be too low, particularly the upper shrouds. Take a picture of your rig if you have a chance. A well set up :macm: rig should have about 2 degrees mast rake aft and a bit of bend in the mast. Also make sure the board and/or lines for the board aren't stuck so you get the full 57" How is the jib halyard tension? Jib car placement and sheeting. Jib sheeting is just as important for upwind performance as main sheeting. One of these should get you plenty of helm to weather.

Leon

Re: weather helm/lee helm

Posted: Sun Oct 07, 2012 5:01 am
by Catigale
Leon..thanks for sticking around post :macm: .....appreciate all that SFO bay sailing experience you pass on!!!

Re: weather helm/lee helm

Posted: Sun Oct 07, 2012 11:21 am
by delevi
Stephen,
The experience I gained with the Mac along with some charters of larger boats made it all possible, i.e. gaining the confidence to go with a larger boat to single-hand. Drop me a line next time you're in my neck of the woods. I know we tried this a few times int he past and schedules didn't work out. Always room for you aboard Akula if you want to go sailing in SF. I'm now moored at Pier 39. 8) 8)

cheers,
Leon

Re: weather helm/lee helm

Posted: Sun Oct 07, 2012 11:56 am
by Crikey
Blee, I tend to agree with Seahouse in this regard: check the toe-alignment of your :macm: 's rudders. Mine (a 2011) were notoriously out of spec. Same too for vertical position! I doubt if biasing too far forward would be a noticeable disadvantage, in this regard, but if toed out - would show a light helm in average conditions but tend to be pushed into a weather helm state when driven too hard. I think the fore aft loading of the hull could be an influence as well.

Ross

Re: weather helm/lee helm

Posted: Tue Oct 09, 2012 7:20 am
by blee
At the beginning of this post, the main reason I wrote the post was that there is a slight leehelm on starboard tack and almost balanced on port tack.

I think I found the reason : Portside stop bolt at the rudder was loosend and lost and the rudder was slanted forward.
I installed new bolt/lock nut and adjusted both rudders vertically.

I also checked the length from the bow to mast raising hookup and found exactly 156" which meant the mast was leaned too far forward prior to I rake backward. Since the forstay length is maxed out, perhaps it is manufactured too short.

Double checked the Center Board. It was all the way down 57" or slightly more than 57".

Checked Shroud tensions. When mast is rotated maximum left or right, lower shround makes mast bend very slightly sideway and both upper shrouds are remain tight so I presume the tightness of upper shrounds are just about right.

Checked rudder toe in or toe out - it seems they are parellel to me.


Then yesterday I was fortunate to have just right wind, 10-15 miles/hr so went out to test sailing.

At about slight more than 10 degree heeling, the boat shows perfectly balanced helm, equally at port or starboard tack!!
I did not have to touch the helm and she beats straight about half mile by herself.

I did not have a chance more than 15 degree heel to try weather helm as my wife would not let me.


As I felt the helm is still too soft so I raked rudder to rearward slightly more but I did not test sailing aftward.

Now it seems the both helm is well balanced at this heel angle. Is it recommended to have the mast raked slightly more to backward so I have more weathehelm? Most book I read about sailing says that one have to have weather helm requiring 3 degree rudder angle toward leeward in beating to make boat most effective.

Thanks for many input.

Re: weather helm/lee helm

Posted: Tue Oct 09, 2012 7:25 am
by Catigale
Generalisations like the 3 degree citation almost always fail, especially when applied to hybrid power sailors like the :macx: or :macm:

Read less, sail more.... :D :D :D

Re: weather helm/lee helm

Posted: Mon May 13, 2013 8:02 am
by Baerkanu
Resurrecting this thread, since it seems appropriate -

We're finally getting some actual sailing time on our 26M - I've spent about 2 weeks on overnight trips, but the weather hasn't cooperated with our desire to sail, even with no set destination in mind. Chalk one up for the 26M's flexibility!

Over the weekend, I found out that I've got horrible lee helm as well - my symptoms matched Blee's problem that he described so well in this thread. Zero steering effort under sail, lee helm etc. The steering was so light that you could spin the wheel when heeled at 5 to 20 degrees, and it would just go to the steering stop. Beyond 20 degrees, if you need two hands to grab a sheet or whatever, the boat dove off the wind very quickly.

After finding this post, I checked the rudders and turned both stops in 2 turns each, so that the rudders trail a bit more (the boat was in the water, so haven't checked alignment as yet). This seemed to help, since the lee helm is much improved on the port tack now (though still there), and on a starboard tack, I've got an appropriate amount of weather helm.

The boat's a 2013, picked up last Sept at BWY, so my first assumption is that it's rigged correctly and that the shroud tension is fine, since I haven't changed anything. When raising the mast, the furler is a bit difficult to hook to it's pin with one person, but not overly so - but when pinned, it does seem to have a bit of slack, which could I suppose mean that the mast needs to be raked back - but I'm afraid that if I do that, it'll be a lot harder to connect. Are furlers normally a bit slack, given their weight?

The boat's on the trailer now at the lake, I'll check the rudder alignment next time we go out.

Thanks,

- Clay

Re: weather helm/lee helm

Posted: Tue May 14, 2013 1:26 pm
by Ixneigh
I guess I'm in the minority since I love the fact that the helm is light even in heavy airs. In fact I'm amazed when I go from full sail, to reefed main and full jib (hank on) to smaller jib to just a reefed main the the helm feel really doesn't change. Ditto with daggerboard adjustment. I consider that some of Rogers genius. All of my other boats had moderate to severe weather helm. I'll take the M any day.
I do disconnect the engine every time I sail. You can trim the rudders back. I think that's the most effective way to add weather helm if you want it.
I do not have a genoa either. Perhaps poorly rolled headsail could contribute to lee helm?
Ix

Re: weather helm/lee helm

Posted: Fri May 17, 2013 9:47 am
by Judy B
Baerkanu wrote:Resurrecting this thread, since it seems appropriate -

We're finally getting some actual sailing time on our 26M - I've spent about 2 weeks on overnight trips, but the weather hasn't cooperated with our desire to sail, even with no set destination in mind. Chalk one up for the 26M's flexibility!

Over the weekend, I found out that I've got horrible lee helm as well - my symptoms matched Blee's problem that he described so well in this thread. Zero steering effort under sail, lee helm etc. The steering was so light that you could spin the wheel when heeled at 5 to 20 degrees, and it would just go to the steering stop. Beyond 20 degrees, if you need two hands to grab a sheet or whatever, the boat dove off the wind very quickly.

After finding this post, I checked the rudders and turned both stops in 2 turns each, so that the rudders trail a bit more (the boat was in the water, so haven't checked alignment as yet). This seemed to help, since the lee helm is much improved on the port tack now (though still there), and on a starboard tack, I've got an appropriate amount of weather helm.

The boat's a 2013, picked up last Sept at BWY, so my first assumption is that it's rigged correctly and that the shroud tension is fine, since I haven't changed anything. When raising the mast, the furler is a bit difficult to hook to it's pin with one person, but not overly so - but when pinned, it does seem to have a bit of slack, which could I suppose mean that the mast needs to be raked back - but I'm afraid that if I do that, it'll be a lot harder to connect. Are furlers normally a bit slack, given their weight?

The boat's on the trailer now at the lake, I'll check the rudder alignment next time we go out.

Thanks,

- Clay
No, furlers are not normally a bit slack. Shrouds are supposed to be snug. If the rig is tuned properly, all the shrouds and stays will be snug. It's a sailboat, so the very first thing to confirm is the rig tuning. I'd really urge you to check your mast rake and then adjust the other shrouds to hold the mast in position. There are instruction in the manual about how to tune the rig. You can do it with the boat on the trailer (on level ground).

Here's what it says about mast rake, in brief.

It should measure 156" from the bow to the mast raising eye. There's a picture of how to measure. That will result in a considerable degree of mast rake.

Also, when you get on the water, make sure sure the boat is floating on her lines. If she's squatted down in the stern, that can increase lee helm/reduce weather helm because it moves the CLR aft.
Plus, if the bow is floating up high, the wind will blow her bow downwind. Move gear around on the boat to make sure her bow isn't sticking up in the air.

Fair winds,
Judy B
Sailmaker