Good Day,
I have commented in a number of places on this forum about my dissatisfaction with the fixed rudder on my boat. I believe it is mostly responsible for the extreme weather-helm I experience. As a result, I have researched on-line and looked through my library of boat books, and have reminded myself that mast rake and sail area proportion (fore and main) can impact on weather-helm too. I am already thinking hard about adding a leading edge to my rudder but before attempting this modification, I think I should experiment with my mast rake first.
In so doing, I will provide the following measure to share with the forum : I will measure, in mm, the distance from the where the mainsail halyard enters the top of the mast (I can attach a tape measure to this and pull it up) to the centre of the transom (under the traveller track - so tiller removed in my case). After each adjustment I will report on weather-helm.
I have a standard headsail and main (as per information found elsewhere on this forum). If forum members have a similar sails I would like to know the rake of their mast using the measure and method described above.
Regards,
Weather-helm
Weather-helm
Peter
Pip #127
Pip #127
Re: Weather-helm
Hi Peter
I to had same problem, I ran a plum bolt from the top of mast to deck set at 3 degree's which appears to be what is required, but i had weather helm! I then just changed the pins on back stays one hole (didnt check with plum bolt again) this has created negative angle on mast, although weather helm is better, I to think a re-think on rudder design would work better, I am currently in the process of making a wind vane system similar to the SCANMAR system with cables and trim tab, so i will be modding original rudder (like the idea of floating rudder for extra floatation) but want it a swing rudder, as i am sick of limitations at gippsland lakes for fixed rudder. let me know if your settings help.
I to had same problem, I ran a plum bolt from the top of mast to deck set at 3 degree's which appears to be what is required, but i had weather helm! I then just changed the pins on back stays one hole (didnt check with plum bolt again) this has created negative angle on mast, although weather helm is better, I to think a re-think on rudder design would work better, I am currently in the process of making a wind vane system similar to the SCANMAR system with cables and trim tab, so i will be modding original rudder (like the idea of floating rudder for extra floatation) but want it a swing rudder, as i am sick of limitations at gippsland lakes for fixed rudder. let me know if your settings help.
Re: Weather-helm
The Investigator 563 normally does not have a problem with weather helm, and essentially it is a problem of balancing the centre of effort of the sails and the underwater area centre of effort.
1. Mast Rake. Raking the mast back will cause weather helm. The mast should be vertical.
2. Sail Balance. Reef the main in a fresh breeze and you will reduce the weather helm.
3. Centre board- lifting it up (back) a bit reduces weather helm.
4. Rudder design- mmm, this one it complicated. see http://www.trailersailerplace.com.au/ph ... m&start=25 for copious discussion.
On rudder design, there have been a few posts on this site regarding a change to a lifting or swinging design. The original was not ideal from a convenience point of view. I believe that Yachtworks, if they are still operating, sell a liftable one for a Castle which works OK. A number of owners have made their own. http://www.investigator563.com/forum/vi ... lit=rudder
http://www.investigator563.com/forum/vi ... lit=rudder
Then there is the drop type, (my preference).
1. Mast Rake. Raking the mast back will cause weather helm. The mast should be vertical.
2. Sail Balance. Reef the main in a fresh breeze and you will reduce the weather helm.
3. Centre board- lifting it up (back) a bit reduces weather helm.
4. Rudder design- mmm, this one it complicated. see http://www.trailersailerplace.com.au/ph ... m&start=25 for copious discussion.
On rudder design, there have been a few posts on this site regarding a change to a lifting or swinging design. The original was not ideal from a convenience point of view. I believe that Yachtworks, if they are still operating, sell a liftable one for a Castle which works OK. A number of owners have made their own. http://www.investigator563.com/forum/vi ... lit=rudder
http://www.investigator563.com/forum/vi ... lit=rudder
Then there is the drop type, (my preference).
Ian B
Ex Investigator 563 #50 Yara
Ex Investigator 563 #50 Yara
Re: Weather-helm
On Sunday I sailed in 12 knots (+18 knot bullets) with a reef in the main and the centre-plate down to where the attachment point was just below the keel (I know this because I took a dip and this was the lowest point I could lever it out to (see other posts)). This would have been about half the plate but the centre of effort position would have been well behind the mast. Just so you know, we were racing; so pointing was important and we were trying to go fast.
The change in centre-plate resulted in a huge difference in feel. The weather-helm was apparent but not arm-wrenching. The boat pointed pretty well, didn't skid to leeward, and was much less susceptible to broaching. Looking out the back of the boat and it was apparent the rudder was providing some lift in its own right - there was a lovely creamy curl of water coming off it rather than the usual untidy froth. It was like thick custard!
Its time to reflect now whether I need to modify my rudder or not. At least for the reason of weather-helm which I appear to have addressed by having the plate set well back. It might be said that the reefing made a difference too, and I suspect it did, but I think the conditions indicated a reef was prudent sailing as we sailed to windward with powered-up mainsail, well heeled over, most of the time. Every so often I needed to let the main sheet off but not too often.
My advice to forum members, for what it might be worth is, to stand your mast up pretty straight, and reef appropriately (where being over powered is not a regular event), and - adjust your centre-plate to reduce excessive weather helm. It really does make all the difference.
The change in centre-plate resulted in a huge difference in feel. The weather-helm was apparent but not arm-wrenching. The boat pointed pretty well, didn't skid to leeward, and was much less susceptible to broaching. Looking out the back of the boat and it was apparent the rudder was providing some lift in its own right - there was a lovely creamy curl of water coming off it rather than the usual untidy froth. It was like thick custard!
Its time to reflect now whether I need to modify my rudder or not. At least for the reason of weather-helm which I appear to have addressed by having the plate set well back. It might be said that the reefing made a difference too, and I suspect it did, but I think the conditions indicated a reef was prudent sailing as we sailed to windward with powered-up mainsail, well heeled over, most of the time. Every so often I needed to let the main sheet off but not too often.
My advice to forum members, for what it might be worth is, to stand your mast up pretty straight, and reef appropriately (where being over powered is not a regular event), and - adjust your centre-plate to reduce excessive weather helm. It really does make all the difference.
Peter
Pip #127
Pip #127
Re: Weather-helm
Starting to reply to myself: Is that self-centered?
I have got the boat home and lined up my Hartley 18 swinging rudder on the pintles of Pip. About 60 minutes of work saw a precise fit and the rudder blade swinging forward of the pintle line. However, the tiller handle wanted to occupy the same place as the track across the back of the transom; so out with the hacksaw (I'll go with a rope horse now). I also ended up with a fixed tiller too. If it works better than the original then I will do something about it.
The Hartley rudder is gal steel about 3-4mm so it is much thinner than the fixed unit it replaced but it is much heavier (20kg). It goes deeper and is wider than the original especially at the top. I suspect it will less inclined to slip than the original - broaches were a very infrequent event in the Hartley (in fact I don't remember any). Perhaps I will be able to carry the full main in stronger winds than I have previously. The Hartley blade can be raised and lowered.
I'll do some measurements of the blade and edit this post accordingly.
I have posted some pictures and what I like is how the front of the rudder blade is slightly forward of the pintles unlike in the original fixed blade where there is a large gap with the pintles ahead of the front of the rudder.
If the experiment does not work any better then no real harm done. It will be easy to change back.
I have got the boat home and lined up my Hartley 18 swinging rudder on the pintles of Pip. About 60 minutes of work saw a precise fit and the rudder blade swinging forward of the pintle line. However, the tiller handle wanted to occupy the same place as the track across the back of the transom; so out with the hacksaw (I'll go with a rope horse now). I also ended up with a fixed tiller too. If it works better than the original then I will do something about it.
The Hartley rudder is gal steel about 3-4mm so it is much thinner than the fixed unit it replaced but it is much heavier (20kg). It goes deeper and is wider than the original especially at the top. I suspect it will less inclined to slip than the original - broaches were a very infrequent event in the Hartley (in fact I don't remember any). Perhaps I will be able to carry the full main in stronger winds than I have previously. The Hartley blade can be raised and lowered.
I'll do some measurements of the blade and edit this post accordingly.
I have posted some pictures and what I like is how the front of the rudder blade is slightly forward of the pintles unlike in the original fixed blade where there is a large gap with the pintles ahead of the front of the rudder.
If the experiment does not work any better then no real harm done. It will be easy to change back.
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Last edited by Dr. Peter on Fri Jan 04, 2013 3:36 pm, edited 2 times in total.
Peter
Pip #127
Pip #127
Re: Weather-helm
As an aside to this topic, I was out sailing on the weekend in Qumbu with a friend who owns an Ultimate 18.
As his boat is the same length as an Investigator and sails off the same handicap (0.59), I was keen for his appraisal of the Investigator's 'feel' compared with his boat.
When he took the helm for a while he was amazed at how 'light' the boat felt, with neither weather or lee helm evident -- something I guess I had gotten used to and just took for granted.
He was very pleasantly surprised at how well QUMBU sailed, especially when the wind picked up a bit to around 12 knots, and we were moving along nicely at about 4.5 knots.
Now we're preparing for a 'grudge race' to pit both boats together. I'll keep you informed.
Cheers,
As his boat is the same length as an Investigator and sails off the same handicap (0.59), I was keen for his appraisal of the Investigator's 'feel' compared with his boat.
When he took the helm for a while he was amazed at how 'light' the boat felt, with neither weather or lee helm evident -- something I guess I had gotten used to and just took for granted.
He was very pleasantly surprised at how well QUMBU sailed, especially when the wind picked up a bit to around 12 knots, and we were moving along nicely at about 4.5 knots.
Now we're preparing for a 'grudge race' to pit both boats together. I'll keep you informed.
Cheers,
Geoff
Investigator 563 'QUMBU'
Geelong, Victoria, Australia
Investigator 563 'QUMBU'
Geelong, Victoria, Australia
Re: Weather-helm
We just completed 9 days sailing in variety of conditions up to 15-20 knots. The try-out Hartley rudder was fitted during this time. Unfortunately, once again, my centre-plate remained firmly housed up in the keel. My great idea to get it moving downward failed on launching from the trailer; it didn't seem to matter.
What we observed:
1. Under the conditions experienced we were able to carry full mainsail. This was not possible before.
2. The boat never once broached. A frequent occurrence with the old rudder. We rarely had to dump much sail in a gust.
3. Weather-helm was very slight in low winds and firmer in stronger breezes.
4. The boat appeared to point and slippage to leeward was unnoticeable as long as the boat was moving well. Pointing was problematic before, to the point that I did not consider Pip to be an around-the-cans boat.
4. The boat appeared to go faster. It stopped less and getting going again after a tack was immediate as long as we did not sheet on too hard.
5. Pulling up the rudder allowed us to maneuver just on the outboard in tricky docking situations (fitting an 18.5 ft boat into a pen designed for a 40 footer).
The Hartley rudder is very non-technical. Basically it is a thin gal plate with a bit of grinding of the edges. It has more surface area (see images above). I was thinking that if this worked I would invest money in a proper rudder like one for a Castle but a friend said why change what you have if it works so well. I think he has a point. However, it is heavy and perhaps something similar in aluminum might be worthwhile thinking about.
Just one thing and I think it is important to note. We never experienced a following sea during our trip and this is a situation which puts the rudder under significant strain. This is a condition that does need testing.
In my opinion, our boat, Pip, has been transformed into a much better performing craft with the replacement of the original fixed rudder even without the benefit of the centre-plate. So much so I am even wondering whether to do anything about the centreplate at all!
What we observed:
1. Under the conditions experienced we were able to carry full mainsail. This was not possible before.
2. The boat never once broached. A frequent occurrence with the old rudder. We rarely had to dump much sail in a gust.
3. Weather-helm was very slight in low winds and firmer in stronger breezes.
4. The boat appeared to point and slippage to leeward was unnoticeable as long as the boat was moving well. Pointing was problematic before, to the point that I did not consider Pip to be an around-the-cans boat.
4. The boat appeared to go faster. It stopped less and getting going again after a tack was immediate as long as we did not sheet on too hard.
5. Pulling up the rudder allowed us to maneuver just on the outboard in tricky docking situations (fitting an 18.5 ft boat into a pen designed for a 40 footer).
The Hartley rudder is very non-technical. Basically it is a thin gal plate with a bit of grinding of the edges. It has more surface area (see images above). I was thinking that if this worked I would invest money in a proper rudder like one for a Castle but a friend said why change what you have if it works so well. I think he has a point. However, it is heavy and perhaps something similar in aluminum might be worthwhile thinking about.
Just one thing and I think it is important to note. We never experienced a following sea during our trip and this is a situation which puts the rudder under significant strain. This is a condition that does need testing.
In my opinion, our boat, Pip, has been transformed into a much better performing craft with the replacement of the original fixed rudder even without the benefit of the centre-plate. So much so I am even wondering whether to do anything about the centreplate at all!
Last edited by Dr. Peter on Fri Jan 25, 2013 11:03 pm, edited 2 times in total.
Peter
Pip #127
Pip #127
Re: Weather-helm
There were some interesting discussions on TSP about the role of the rudder in yacht balance. It is generally agreed that the rudder does contribute, and a larger rudder, even in midships position, does provide some underwater lift.
I am afraid that without the centreplate, even if the bow is pointing nicely into the wind, the course made good is fairly pathetic. Do you have a flat grass area you could launch your boat onto? This technique for centreplate replacement is described in the old Investigator literature, where the boat is rolled on its side on old car tyres. A sandblast and re- galvanising may be all it needs.
I am afraid that without the centreplate, even if the bow is pointing nicely into the wind, the course made good is fairly pathetic. Do you have a flat grass area you could launch your boat onto? This technique for centreplate replacement is described in the old Investigator literature, where the boat is rolled on its side on old car tyres. A sandblast and re- galvanising may be all it needs.
Ian B
Ex Investigator 563 #50 Yara
Ex Investigator 563 #50 Yara
Re: Weather-helm
My kick up rudder is same format as your Hartley unit except that the blade is a full foil, probably the same width as yours but from the pic I'd guess 250mm or so longer. The foil is about 45-50mm thick. It is slightly balanced as well, i.e. the leading edge is level with the transom which means it is forward of the pivot point of the pintles
Re: Weather-helm
We were out off Freo today when the seabreeze caught us fair way from home, we couldn't just run all the way back, we had to stay out there and really work to get back to Woodman point. The sea was getting quite lumpy too. Weather helm was really a non issue and only experiencing slight weather helm on excessive heal, most likely instigated by swell. Basically we followed Ian's advice:
Center plate slightly aft,
Traveler leeward,
Backstay tensioned tight along with the boom vang
Then main sail reefed down hard and tight
Also importantly we kept the jib driving hard with good power some times a bit of leehelm was present.
All the helmsman need to do was ease the mainsheet to reduce heal in gusts and the rudder stayed light and straight, speed stayed constant.
Wind was 24kts and gusting higher and we were in open waters. I had felt a litte anxious about sailing these conditions especially with the helm problems I first experienced in wind aprox 20kts .
The 563 handled the conditions beautifully and has given me allot more confidence and I really enjoyed being out there.
In conclusion , set up the known variables like center plate, mast and traveler, de power the main and keep the jib full and driving, Seemed to work for us
Steve
Center plate slightly aft,
Traveler leeward,
Backstay tensioned tight along with the boom vang
Then main sail reefed down hard and tight
Also importantly we kept the jib driving hard with good power some times a bit of leehelm was present.
All the helmsman need to do was ease the mainsheet to reduce heal in gusts and the rudder stayed light and straight, speed stayed constant.
Wind was 24kts and gusting higher and we were in open waters. I had felt a litte anxious about sailing these conditions especially with the helm problems I first experienced in wind aprox 20kts .
The 563 handled the conditions beautifully and has given me allot more confidence and I really enjoyed being out there.
In conclusion , set up the known variables like center plate, mast and traveler, de power the main and keep the jib full and driving, Seemed to work for us
Steve