ianabc
Well-Known Member
Easier helming
reefing ideas for a Colin Archer design please.....
reefing ideas for a Colin Archer design please.....
Last edited:
37 foot steel Colin Archer ( long keel) much effort needed on tiller
- Thread starter ianabc
- Start date
alahol2
Well-Known Member
I'm sure I have seen a self steering design where a miniature 'tab' rudder is fixed to the rear edge of the main rudder blade. The water pressure on the mini-rudder is used to turn the main rudder. An interesting design exercise for someone?
William_H
Well-Known Member
Trim tab
The trim tab idea is common on aircraft control surfaces. However they do make things complicated.
I think more rudder balance is needed. I understand that this is not easy with a rudder hung on the back of the keel. Perhaps you might consider another transom mounted rudder very deep with balance. try about 15% area forward of pintle.
Or you might consider extending the existing rudder deeper ie deeper than the keel such that some area can be fitted forward of the shaft line. This added area you could make is fibreglass on foam such that it could easily be torn off if it catches on something or is grounded.
Meantime a piece of bungee cord could provide some extra help assuming she is pulling always to overcome weather helm. The weather helm is almost certainly comes from too much heel. You may find that you go faster with less heel by reducing jib area. Faster with less rudder drag. good luck olewill
The trim tab idea is common on aircraft control surfaces. However they do make things complicated.
I think more rudder balance is needed. I understand that this is not easy with a rudder hung on the back of the keel. Perhaps you might consider another transom mounted rudder very deep with balance. try about 15% area forward of pintle.
Or you might consider extending the existing rudder deeper ie deeper than the keel such that some area can be fitted forward of the shaft line. This added area you could make is fibreglass on foam such that it could easily be torn off if it catches on something or is grounded.
Meantime a piece of bungee cord could provide some extra help assuming she is pulling always to overcome weather helm. The weather helm is almost certainly comes from too much heel. You may find that you go faster with less heel by reducing jib area. Faster with less rudder drag. good luck olewill
LittleSister
Well-Known Member
As a previou post suggests, reefing deeper is going to be your most effective response. However, I seem to recall that Colin Archer style vessels were fairly notorious for being heavy on the helm.
You could also try adjusting the trim of the boat by shifting ballast (and other weight) aft, or reducing that in the bow, which might help.
You could also try adjusting the trim of the boat by shifting ballast (and other weight) aft, or reducing that in the bow, which might help.
owen-cox
Well-Known Member
My boat is very similar a 30ft steel long keel sloop www.steelyacht.co.uk and she suffers the same I find it very important to reef the main first and try to maintain the genoa size to exert a larger force at the bow. this decreases weather helm and makes life much easier. you have to be careful though as the boat tends not to luff as usual so you have to be a bit wary about knockdowns in gusts.
Bosun Higgs
N/A
Its some time since I last steered a dinghy under sails alone but I seem to remember that the cure for rounding up was to sheet in the main and free off the jib. Might be the other way round. So I would try altering the sail areas ( more main less jib) and altering the sheeting first
That may not be the whole answer because some hulls are so badly designed they round up just because they are heeling, but if your tiller is normally reasonably light then the problem you describe shows that the boat is being over pressed in heavy winds. The problem with steel as a boat building material is that in smaller loa's there can be so much weight in the hull that the ballast ratio is poor and the boat does not stand up to its sail very well.
That may not be the whole answer because some hulls are so badly designed they round up just because they are heeling, but if your tiller is normally reasonably light then the problem you describe shows that the boat is being over pressed in heavy winds. The problem with steel as a boat building material is that in smaller loa's there can be so much weight in the hull that the ballast ratio is poor and the boat does not stand up to its sail very well.
Kelpie
Well-Known Member
I'm pretty sure it's the other way around! The headsail is trying to blow the bows off downwind which acts against weather helm, whilst the main is behind the centre of effort and is what makes the boat want to round up.
But of course the heeling itself has an effect so it's a combination of things.
In Wayfarers, it is very tempting to reduce mainsail and leave the whole genoa up to keep the boat balanced- but those who know what they're doing advise against this and say you should reduce headsail as well. Something to do with 'choking the slot' apparently?
But of course the heeling itself has an effect so it's a combination of things.
In Wayfarers, it is very tempting to reduce mainsail and leave the whole genoa up to keep the boat balanced- but those who know what they're doing advise against this and say you should reduce headsail as well. Something to do with 'choking the slot' apparently?
prv
Well-Known Member
I don't have any specialised knowledge of the effects of heel, but since my rig is long and low (35 foot sailplan on a 24 foot hull, using both a bowsprit and a bumkin) and has a shallow draught without much of a well-defined keel, I have to keep on top of sail balance at all times. Going to windward, when weather helm can be a problem, I have to reef from the stern forward. I'll have both reefs down in the main (and the mizzen completely down and stowed) before I touch the jib.
If she'll stand it, perhaps you need to hang onto the bigger headsail for longer?
Pete
If she'll stand it, perhaps you need to hang onto the bigger headsail for longer?
Pete
Tranona
Well-Known Member
Think i would agree that increasing headsail area (relatively) so moving the C of E forward is one way of relieving weather helm. However, think one has to accept that heavy long keel boats with rudders that are on the small side and no balance area tend to have heavy helms. Remember all those old pictures of two people on the helm and relieving tackles set up. They weren't just for dramatic effect!
lw395
Well-Known Member
Does the rudder have to move far to steer the boat? It could be that a smaller rudder would work better. Less chord would improve your leverage against the rudder as well as reducing the area nad hence force. Obviously having too small a rudder will be disastrous.
Alternatively some power assistance from either an autopilot or vane steering gear might help.
I suspect balance of the rig is not the issue, so much as the way the balance changes as the boat heels?
It's a big old boat for tiller steering, you are asking quite a lot for a smallish lady to be able to handle it in what is quite a lot of wind by any reasonable standards.
Is wheel steering an option?
If the issue is the balance changing as the boat heels, would raising the jib up the forestay help, as the jib would depower less when heeled, due to being in clearer air etc.?
Maybe a higher clew jib?
prv
Well-Known Member
Looking at living with the weather helm rather than preventing it, I've seen Essex smacks fitted with tackles either side of the tiller which they routinely steer with instead of the tiller itself, in stronger winds. Smaller ones have a line made fast at the bulwark which they pass round the end of the tiller and back to the helmsman, to make a simple purchase without blocks.
Pete
D
Deleted member 36384
Guest
Ease the main. The drag caused by the rudder is slowing you anyway, so reduce power slightly. Perhaps you need to fit a traveller or add one of those powerful pulleys to make easy adjustments to the main which would allow your wife to ease the main.
William_H
Well-Known Member
Weather helm and steering
A few months back I did an exercise on a fairly sporty 8 metre boat. It was part of an instructor update. I was supposed to be teaching the steering of the boat through figure 8 without touching the rudder.
The different forces of steering are used to steer the boat on different points of wind.
So Head to wind you back the jib to get the boat to steer out of irons and this backing can be useful to nearly 90 degrees from wind.
When on a reach the relative pressures of the jib versus main sail will in the classic manner turn the boat down wind or up wind. However once you get close to the wind the effect seemed much less.
Heeling the boat gave a very useful turning action the low side being on the outside of the turn so you can turn the boat into the wind then use the backing jib to continue the turn.
We got it working so well that a lifejacket was thrown in for the classic MOB recovery without rudder. And we got it back on board. The tiller was tied off central all the time.
My point is that balance of sail pressure was most apparent on a reach not so much when beating into the wind. The turning motion of heeling is very powerful although it depends on shape of the hull. olewill
A few months back I did an exercise on a fairly sporty 8 metre boat. It was part of an instructor update. I was supposed to be teaching the steering of the boat through figure 8 without touching the rudder.
The different forces of steering are used to steer the boat on different points of wind.
So Head to wind you back the jib to get the boat to steer out of irons and this backing can be useful to nearly 90 degrees from wind.
When on a reach the relative pressures of the jib versus main sail will in the classic manner turn the boat down wind or up wind. However once you get close to the wind the effect seemed much less.
Heeling the boat gave a very useful turning action the low side being on the outside of the turn so you can turn the boat into the wind then use the backing jib to continue the turn.
We got it working so well that a lifejacket was thrown in for the classic MOB recovery without rudder. And we got it back on board. The tiller was tied off central all the time.
My point is that balance of sail pressure was most apparent on a reach not so much when beating into the wind. The turning motion of heeling is very powerful although it depends on shape of the hull. olewill
westernman
Well-Known Member
Not really.
This is a big old boat for tiller steering:-
http://www.flickr.com/photos/33847785@N00/3955861922/
Brent Swain
N/A
Steering problems
I had the same problem with my first boat. Rudder too far forward. Pulled the rudder off the keel and put in a skeg hung rudder, six feet further aft. Worked like a charm.
I'm on the green boat on the mud flats, behind the condos in Comox. Row over some time and we can discuss the problem.
Brent
I had the same problem with my first boat. Rudder too far forward. Pulled the rudder off the keel and put in a skeg hung rudder, six feet further aft. Worked like a charm.
I'm on the green boat on the mud flats, behind the condos in Comox. Row over some time and we can discuss the problem.
Brent
Bajansailor
Well-Known Member
I sailed with some friends once on their 39' 17 tonne ferro-cement Colin Archer gaff ketch from Southampton to Portugal, and she was VERY heavy on the helm all of the time, even when motoring.
The reason was probably because she had a very large rudder with no balance at all on her double ended stern. When sailing she was lovely - she was very directionally stable, and would tromp along happily with the sails balanced, and she had an Aries vane gear as well - it was easier to keep the Aries connected and use it's control lines to move the rudder than to try and heave the tiller across.
Chuck Paine has designed Expannie, a lovely larger version of his 30' Annie, with the problems of a heavy helm in mind, and has managed to introduce a bit of balance to the rudder by cutting away some of the 'deadwood' forward of it - have a look at these excellent 3-D drawings in the pdf on his website (altho' be warned, it is almost 7 MB in size to download).
http://www.chuckpaine.com/pdf/36EXPANNIE36.pdf
He also suggests building the rudder out of carbon fibre to reduce its weight, and hence the force required to overcome its inertia when altering course.....
The reason was probably because she had a very large rudder with no balance at all on her double ended stern. When sailing she was lovely - she was very directionally stable, and would tromp along happily with the sails balanced, and she had an Aries vane gear as well - it was easier to keep the Aries connected and use it's control lines to move the rudder than to try and heave the tiller across.
Chuck Paine has designed Expannie, a lovely larger version of his 30' Annie, with the problems of a heavy helm in mind, and has managed to introduce a bit of balance to the rudder by cutting away some of the 'deadwood' forward of it - have a look at these excellent 3-D drawings in the pdf on his website (altho' be warned, it is almost 7 MB in size to download).
http://www.chuckpaine.com/pdf/36EXPANNIE36.pdf
He also suggests building the rudder out of carbon fibre to reduce its weight, and hence the force required to overcome its inertia when altering course.....