Sailing with a Dragonfly in bad weather

[Claude]

hello,

I am thinking about buying a Dragonfly but I wonder how this boat behaves in bad weather: strong wind and rough sea. Does any have such an experience sailing either downwind or upwind. What about using the motor in such conditions.

claude

[Ipe Piccardt Brouwer]

John Blaiklock wrote something about this on the old forum. I think he says it rather well so I'll copy it here:

Re: How does the DF920 perform in rough seas ?
[from: John Blaiklock, United Kingdom, 15 Sep 2004]
sail my 920 in the Irish Sea and the South West coast of Scotland. Although this is not water open to ocean weather and sea conditions, it is not sheltered water either. Our strong tides can make for lumpy waves. The East coast of the UK will be similar.

As far as safety and seaworthiness goes, the DF920 will perform just as well in rough seas that any modern similar sized mono-hull boat will from any of the current main manufacturers. A low F6 will be safe and without problem. A rough F7 or above will feel like time to find shelter. A DF920 will be no better or worse than say a Beneteau 31.7. It will not be as seaworthy as a boat like a Contessa 32. It is not designed to be, and few small boats now are. You need to remember, it is only a 9.2m boat. It is not designed for oceans.

As far as comfort goes, few small boats are comfortable in open-water waves from wind above F6, and the DF920 is no exception. There are advantages and disadvantages compared to a similar sized mono-hull. Rolling and heeling is much less, slamming is less, but low weight makes for jerky movements. Cooking a meal in a lumpy F6 will be tricky but not impossible.

High speed performance in rough weather cannot be expected from a small trimaran. As the waves increases the boat needs slowing down. 18 knots off the top of a 3m wave and into the back of the next one is not a good idea. You will still beat the monos, but speed needs to be limited, specially going into the waves. In an open-water F6 7 knots upwind and 11 knots reaching or downwind is a good compromise between speed and comfort.

I have found sailing upwind ability in strong conditions to be significantly better than a modern mono. The narrow hulls virtually never slam, which is what kills upwind speed and pointing on a mono.

The downside is the outboard engine performance into a sea. If the waves are steep it doesn't take much for the propeller to come out of the water. The solution is either to 'tack' upwind under power, or sail. I have never not been able to motor when I wanted to because of this, but you need to be prepared. This is less of a problem than it sounds, because the upwind sailing ability is so much better than modern fat mono-hulls.

[Double Horizon]

hello,

I am thinking about buying a Dragonfly but I wonder how this boat behaves in bad weather: strong wind and rough sea. Does any have such an experience sailing either downwind or upwind. What about using the motor in such conditions.

claude

Claude, what size Dragonfly are you interested in? I would not want to be on any boat in a hurricane or major storm offshore. When you ask about "strong wind and rough sea" how much wind and what size seas? The shape of the seas can also make a big difference, waves that are formed when the wind is against the current are much steeper, closer spaced and more difficult.

In general the smaller Dragonfly boats are well-suited for coastal sailing. The larger the boat, the better -- in bad weather. If waves become large and steep you will want to slow the boat down, and that is not fun sailing.

The Dragonflies will sail very well to weather (upwind). The smaller models (with outboard) must be sailed to weather in very big waves because the outboard engines will come out of the water at times, but the larger ones (with inboard engines) can be motored to weather. In very strong winds you would probably make better progress by sail in any direction (compared with motoring).

Downwind, the following goes for ANY multihull: Although the Dragonflies have plenty of buoyancy in the bows, you must not carry too much sail. The danger is if you bury the bows in the back of a wave and slow the boat it causes the apparent wind to rise suddenly. You have a risk of pitch-pole if it becomes enough to overpower the boat.

Reaching you have many options, but in general (in any multihull) you should reef for the gusts, not for the average wind speed.

[buckle.roger]

I am in my first season with a 920 touring number 55. great sailing after my hunter 43.
Problem yesterday was worrying,
In 18 kns of wind and a sloppy sea doing around 13 to 14 kns 50 deg on the wind the windward backstay jammer started to slip a few Cms at a time, then the same happened with the downwind ama jammer, any ideas. is it a good idea to fit a cleat for fresh condtions as back up?

The ama was moveing a little when hitting a wave, is this normal ?

How do you know when the ama outhaul line has been tightend enough ?

[Double Horizon]

I am in my first season with a 920 touring number 55. great sailing after my hunter 43.
Problem yesterday was worrying,
In 18 kns of wind and a sloppy sea doing around 13 to 14 kns 50 deg on the wind the windward backstay jammer started to slip a few Cms at a time, then the same happened with the downwind ama jammer, any ideas. is it a good idea to fit a cleat for fresh condtions as back up?

The ama was moveing a little when hitting a wave, is this normal ?

How do you know when the ama outhaul line has been tightend enough ?

The jammers should not slip to a noticeable degree. You might have a problem with them or perhaps you are not using the correct line for them (perhaps replaced by a prior owner?). You should consult a professional rigger or your Dragonfly dealer. The standard line in a 920 Touring is 10mm Polyester double-braid with Spectra core for folding lines, and ordinary 10mm Polyester double-braid for the back-stays. Over time the folding lines will loosen a bit, and you will know that by how tight the nets are tensioned. Just tighten them when needed.

One thought -- your backstay jammers (rope clutches) might slip if you over-tensioned them. You should NEVER tension the leeward backstay (if the leeward one is too loose then tension the windward one more) and never use more than one hand on the winch handle to tension the backstay.

As for the ama moving a little -- yes it is normal. You may hear creaking also, but don't worry. Check your pivot bolts are tight, but not so tight that they interfere with folding. Your water stays should also be checked for proper adjustment; they should have only slight tension when the boat is fully-opened and back-stays are eased. One more thing -- your water stays should be replaced every 5 years as preventive maintenance (required for safety and recommended by Quorning).

[buckle.roger]

I am in my first season with a 920 touring number 55. great sailing after my hunter 43.
Problem yesterday was worrying,
In 18 kns of wind and a sloppy sea doing around 13 to 14 kns 50 deg on the wind the windward backstay jammer started to slip a few Cms at a time, then the same happened with the downwind ama jammer, any ideas. is it a good idea to fit a cleat for fresh condtions as back up?

The ama was moveing a little when hitting a wave, is this normal ?

How do you know when the ama outhaul line has been tightend enough ?

The jammers should not slip to a noticeable degree. You might have a problem with them or perhaps you are not using the correct line for them (perhaps replaced by a prior owner?). You should consult a professional rigger or your Dragonfly dealer. The standard line in a 920 Touring is 10mm Polyester double-braid with Spectra core for folding lines, and ordinary 10mm Polyester double-braid for the back-stays. Over time the folding lines will loosen a bit, and you will know that by how tight the nets are tensioned. Just tighten them when needed.

One thought -- your backstay jammers (rope clutches) might slip if you over-tensioned them. You should NEVER tension the leeward backstay (if the leeward one is too loose then tension the windward one more) and never use more than one hand on the winch handle to tension the backstay.

As for the ama moving a little -- yes it is normal. You may hear creaking also, but don't worry. Check your pivot bolts are tight, but not so tight that they interfere with folding. Your water stays should also be checked for proper adjustment; they should have only slight tension when the boat is fully-opened and back-stays are eased. One more thing -- your water stays should be replaced every 5 years as preventive maintenance (required for safety and recommended by Quorning).

Hi thanks for that most helpfull I will check rope sizes and will take note of backstay tensions.However I still dont know how much effort to put into the outhaul lines for the amas. can you help on this one please

[Double Horizon]

Hi thanks for that most helpfull I will check rope sizes and will take note of backstay tensions.However I still dont know how much effort to put into the outhaul lines for the amas. can you help on this one please

[/quote]

Tight enough to hold the amas open, and tight enough so that the nets are under some tension and do not sag. If you are strong you should not need to use more than one hand on the winch handle at slow speed (high power). You must use judgment -- evaluate the strength of the fittings and know that it is OK if the nets move, but the beams must be fully locked open.

[buckle.roger]

Hi thanks for that most helpfull I will check rope sizes and will take note of backstay tensions.However I still dont know how much effort to put into the outhaul lines for the amas. can you help on this one please

Tight enough to hold the amas open, and tight enough so that the nets are under some tension and do not sag. If you are strong you should not need to use more than one hand on the winch handle at slow speed (high power). You must use judgment -- evaluate the strength of the fittings and know that it is OK if the nets move, but the beams must be fully locked open.[/quote]

Thanks Larry you are most helpful.
The thing is I am now a little worried, I am a practical guy with plenty of sailing experience but not in perfoprmance tris and am reasonable strong
.
Looking at the turning blocks uesd I can se your point about too mch heave ho on the winch however
On my 920 unless I heave VERY hard with two hands the ama move when sailing, the tramp is ok to walk on no problem BUT the diaganal tape running across the tramp is not tight, should it be, however tight the outhaul is the tape across the tramp does not tighten, the shackels are moveable by hand. I have cheched the bocks and all looks free

Thanks again

Roger

[Double Horizon]

Thanks Larry you are most helpful.
The thing is I am now a little worried, I am a practical guy with plenty of sailing experience but not in perfoprmance tris and am reasonable strong
.
Looking at the turning blocks uesd I can se your point about too mch heave ho on the winch however
On my 920 unless I heave VERY hard with two hands the ama move when sailing, the tramp is ok to walk on no problem BUT the diaganal tape running across the tramp is not tight, should it be, however tight the outhaul is the tape across the tramp does not tighten, the shackels are moveable by hand. I have cheched the bocks and all looks free

Thanks again

Roger

Roger if it takes too much force there is something wrong. You must examine each component (and any connected components that may impose restrictions) and make a diagnosis. Check waterstay adjustments. Look inside the aft beam to see if any components are twisted or kinked or wrapped around each other. The folding mechanism is nicely documented in the owners manual.

You don't need to be a gorilla to operate one of these boats.

If you can't diagnose it yourself get help from a rigger, your Dragonfly dealer or other Dragonfly owners in your area who can examine closely. Good luck.

[Steve B.]

Roger,

Take a look at the diagonal tape when you are unfolding the boat. It goes tight while the boat is first being unfolded. The purpose of it is to take up the initial rather extreme load when that load cannot be spread over the area of the mat. Once the mat is opened up, it takes the load over its entire area.

Steve B.

On my 920 unless I heave VERY hard with two hands the ama move when sailing, the tramp is ok to walk on no problem BUT the diaganal tape running across the tramp is not tight, should it be, however tight the outhaul is the tape across the tramp does not tighten, the shackels are moveable by hand. I have cheched the bocks and all looks free

Thanks again

Roger

[buckle.roger]

Thanks Larry you are most helpful.
The thing is I am now a little worried, I am a practical guy with plenty of sailing experience but not in perfoprmance tris and am reasonable strong
.
Looking at the turning blocks uesd I can se your point about too mch heave ho on the winch however
On my 920 unless I heave VERY hard with two hands the ama move when sailing, the tramp is ok to walk on no problem BUT the diaganal tape running across the tramp is not tight, should it be, however tight the outhaul is the tape across the tramp does not tighten, the shackels are moveable by hand. I have cheched the bocks and all looks free

Thanks again

Roger

Roger if it takes too much force there is something wrong. You must examine each component (and any connected components that may impose restrictions) and make a diagnosis. Check waterstay adjustments. Look inside the aft beam to see if any components are twisted or kinked or wrapped around each other. The folding mechanism is nicely documented in the owners manual.

You don't need to be a gorilla to operate one of these boats.

If you can't diagnose it yourself get help from a rigger, your Dragonfly dealer or other Dragonfly owners in your area who can examine closely. Good luck.

You are being very helpfull. I have checked all pullies but I think I will look further and lubricate them too.
My problem is there is no df agent is Spain and only one other owner that I know of who only speaks spannish and has no more experience than me.

I guess the issues is all around how tight is tihght, but one hand on a winch is a good guide, then how much movement is ok on the arms when punching into a sea.
twice now i have been sailng 12 to 15 kns, 50 to 60 deg into 20 to 24 kns aparent wind with a sloppy sea with full sail, lots of spray but no green water on the boat and the ama was banging against the saftey bar several times,

Also the boat is so dam stiff under sail it is difficult to know when she is over pressed, do you fancey trying to describe when that is

The hand book gives wind speeds to reef but does not say if they are true or apparent speeds
I do not know what is normal for this.

[buckle.roger]

Thanks Larry you are most helpful.
The thing is I am now a little worried, I am a practical guy with plenty of sailing experience but not in perfoprmance tris and am reasonable strong
.
Looking at the turning blocks uesd I can se your point about too mch heave ho on the winch however
On my 920 unless I heave VERY hard with two hands the ama move when sailing, the tramp is ok to walk on no problem BUT the diaganal tape running across the tramp is not tight, should it be, however tight the outhaul is the tape across the tramp does not tighten, the shackels are moveable by hand. I have cheched the bocks and all looks free

Thanks again

Roger

Roger if it takes too much force there is something wrong. You must examine each component (and any connected components that may impose restrictions) and make a diagnosis. Check waterstay adjustments. Look inside the aft beam to see if any components are twisted or kinked or wrapped around each other. The folding mechanism is nicely documented in the owners manual.

You don't need to be a gorilla to operate one of these boats.

If you can't diagnose it yourself get help from a rigger, your Dragonfly dealer or other Dragonfly owners in your area who can examine closely. Good luck.

To try and give you a fuller picture, this is in adition to a post 5 minutes ago.
My amas fold out freely to a point about 1 cm from fully closed, i found that a quick walk on the tramp pulls the aras full closed and I just take up the slack no problem here , as I have said in my other entry it is the amount of movement that is accepteble i guess is the issue, am i pushing to windward too hard ?
The outhaul lines are 8mm pale blue and quite hard and stiff, i assume they are orijinal and are spectra ? When winding in hard there is no freel of streching so i assume they are ok.

Once again thank you very much for your help, I am very excited about the df and the way she sails and would like to get the most out of her without haveing a raceing crew, just me and odd friends, so fast but safe is needed

The df is the first boat I have had that is tied together with string so to speak and learning trust of these systems is my issure after fully understanding them of course.

PS just a thought but IF you should fancey a holliday in eastern Spain we have the room and the boat to sailm swaqp a room for some df leasons ????? Season here is more or lest all year, great weather

[gminkovsky]

A few comments:

The reefing table is for TRUE wind. By my calculation, at 60 degrees of aparent wind, your true wind is well over 20 knots! you should reef!

In higher winds, the backstay line must be on the winch. The locks will not hold.

The amas move in high winds. The leeward backstay becomes loose. It does not need to be adjusted. The tramplone's diagonal tape is loose when the boat is open.

[David Hyland]

Thought this clip would give you an idea of 920 under full sail in 25 kt winds....

http://uk.youtube.com/watch?v=L3aoJLai5F8

Obviously, we were over-powered but were in relatively sheltered, flat water. We buried the lee hull a few minutes after this clip and had to let go of the main...... we put a single reef in the main and a few rolls in the genoa for the rest of the trip and stayed in control even though winds were gusting to 32 kts at times.

I would agree with previous remarks that backstays ought to be on the winches for added security and set tight.

Hope this helps.

Dave Hyland

[buckle.roger]

Thought this clip would give you an idea of 920 under full sail in 25 kt winds....

http://uk.youtube.com/watch?v=L3aoJLai5F8

Obviously, we were over-powered but were in relatively sheltered, flat water. We buried the lee hull a few minutes after this clip and had to let go of the main...... we put a single reef in the main and a few rolls in the genoa for the rest of the trip and stayed in control even though winds were gusting to 32 kts at times.

I would agree with previous remarks that backstays ought to be on the winches for added security and set tight.

Hope this helps.


OK gents thank you for the comments, I am getting the feel for what to look out for. I think my one remaining concern is the jammers on the folding mechanism, if it is normal for the backstay jammers to slip under big load what about the folding jammers, I understand the structure will flex and the leeward back stay will then ease but I am concernd about the amouit of movment for and aft of the amsa that may be normal. When I bought the boat the saftey struts had very oval holes which indicates that the amas were moveing and useing the struts as a limit, should the struts be takeing any load when beating to windward in particular
Dave Hyland

[David Hyland]

I've never had a problem with the folding mechanism jammers - I suspect because the load in this area is less - the support struts and the water-stays combining to counter any movement.

One thing I do have as additional security are extra lines from the ends of the forward armas to the bow cleats (essentially copying the extra lines provided as standard on the Extreme model).

Hope this helps.

Dave Hyland

[David Hyland]

I forgot to mention, my 2001 model has the same 'features' - there is some flexing of the armas (and hull for that matter) which I believe is normal from what I've heard from other owners and as a result I also have the oval holes in the struts.

[tpaliwoda]

I fixed that oval hole problem this past spring on my 1000. If anyone really wants to know how to do it, we should most likely start a new thread.
Not a hard fix, just hard to find the parts!
Ted

[gminkovsky]

To David Hyland:

can you describe in detail and possibly post pictures of your setup of additional lines from amas to bow cleat. I've been thinking of adding them too.

Thanks.

[buckle.roger]

I fixed that oval hole problem this past spring on my 1000. If anyone really wants to know how to do it, we should most likely start a new thread.
Not a hard fix, just hard to find the parts!
Ted

OK it is good to know the oval holes or not uncommon. so the amas DO need the struts for support, i thought they were just a saftey device, should one open out and fit the pin and then pull the inhaul tight against the pin to limit movment ?

More info on your fix please

[Double Horizon]

OK it is good to know the oval holes or not uncommon. so the amas DO need the struts for support, i thought they were just a safety device, should one open out and fit the pin and then pull the inhaul tight against the pin to limit movment ?

More info on your fix please

[/quote]

The struts are safety backup. You should not pull the inhaul tight after opening. The primary holding mechanism is the folding lines and nets, but do not sail without the struts (or bow stays to the forward crossbeams). Also for the 1000 owners -- you should install your own bow stays if you don't already have them. The struts on the 1000 may not be adequate.

[buckle.roger]

OK it is good to know the oval holes or not uncommon. so the amas DO need the struts for support, i thought they were just a safety device, should one open out and fit the pin and then pull the inhaul tight against the pin to limit movment ?

More info on your fix please

The struts are safety backup. You should not pull the inhaul tight after opening. The primary holding mechanism is the folding lines and nets, but do not sail without the struts (or bow stays to the forward crossbeams). Also for the 1000 owners -- you should install your own bow stays if you don't already have them. The struts on the 1000 may not be adequate.[/quote]

Thanks again Larry, I sail in the Mediteranian and get a short nasy sea often with little wind so this issue of the for and aft movment of the amas is important to me. Can you give more details on the forward stay modification and again how much tension to put into it,
My fix to the oval holes in the struts was to turn them 90 degs and re drill the holes, wont stop it happening again but is better than nothing

[buckle.roger]

I fixed that oval hole problem this past spring on my 1000. If anyone really wants to know how to do it, we should most likely start a new thread.
Not a hard fix, just hard to find the parts!
Ted

Ted can you give full details for your mod.my tempary fix was to turn the struts 90 degs and re drill them

[David Hyland]

somebody asked for pictures of how the safety lines set up.....hopefully you can see in this video clip:

http://www.youtube.com/watch?v=kBwC6UMoI_c

[Double Horizon]

Thanks again Larry, I sail in the Mediteranian and get a short nasy sea often with little wind so this issue of the for and aft movment of the amas is important to me. Can you give more details on the forward stay modification and again how much tension to put into it,
My fix to the oval holes in the struts was to turn them 90 degs and re drill the holes, wont stop it happening again but is better than nothing

Roger if you have the 1000 with bowsprit the forward attachment point is easy: You should remove a 10mm bolt on each side of the sprit (the one that bolts the sprit to the hull) and replace it with a 10mm eye-bolt (3/8" is also a suitable replacement for 10mm, they are almost exactly the same size). I used the aft-most bolt for Symmetri, but I recommend to use the bolt ahead of that so the wire safety stay doesn't interfere with an anchor or mooring line to the bow cleat. If you don't have a factory-installed sprit you will have a bigger job, because you cannot simply drill the fiberglass there (it won't be strong enough) -- you will need to reinforce the areas on each side of the bow with solid fiberglass and a backing plate to spread the load, then drill for the eye-bolt.

The boat should be fitted to a heavy U-bolt on the forward facing side of the outer end each front cross-beam. Newer boats were provided with those U-bolts from the factory, but if you need to install them they should be placed in the vicinity of the plastic access ports for the ama attachment bolts, or just slightly inboard of those ports. The fiberglass in that beam-end attachment area is solid and thick (strong), so the backing bar that usually comes with U-bolts should be positioned inside the beam, between the U-bolt-heads, and that should be adequate to spread the bolt load.

I used 6mm 1x19 stainless wire, with conventional rigging fittings. The US equivalent is 1/4" wire. I used a conventional fork fitting at the bow with clevis and cotter pins. At the beam end I used a turnbuckle (to allow fine adjustment) and snap-shackle. The type of pelican hooks used in lifelines would be better, and an alternative material to wire rope would be Dyneema or Spectra line. Of course, you should do your own research and evaluation of materials to be sure they will be strong enough, and make sure it is very low-stretch and you have a way to make fine adjustments. Tension should be low enough to enable you to detach the safety stay easily when you need it out of the way for folding or to pick up a mooring, but tight enough so the amas cannot move aft more than a ~centimeter in the event the folding cable mechanism fails.

My disclaimer is that all of the above advice is "home-grown" engineering. I think it was strong enough but it was never tested because I never had a folding system failure. My "standard" was to use materials and fittings that are at least as strong as Quorning used in the primary folding mechanism.

[buckle.roger]

Thanks again Larry, I sail in the Mediteranian and get a short nasy sea often with little wind so this issue of the for and aft movment of the amas is important to me. Can you give more details on the forward stay modification and again how much tension to put into it,
My fix to the oval holes in the struts was to turn them 90 degs and re drill the holes, wont stop it happening again but is better than nothing

Roger if you have the 1000 with bowsprit the forward attachment point is easy: You should remove a 10mm bolt on each side of the sprit (the one that bolts the sprit to the hull) and replace it with a 10mm eye-bolt (3/8" is also a suitable replacement for 10mm, they are almost exactly the same size). I used the aft-most bolt for Symmetri, but I recommend to use the bolt ahead of that so the wire safety stay doesn't interfere with an anchor or mooring line to the bow cleat. If you don't have a factory-installed sprit you will have a bigger job, because you cannot simply drill the fiberglass there (it won't be strong enough) -- you will need to reinforce the areas on each side of the bow with solid fiberglass and a backing plate to spread the load, then drill for the eye-bolt.

The boat should be fitted to a heavy U-bolt on the forward facing side of the outer end each front cross-beam. Newer boats were provided with those U-bolts from the factory, but if you need to install them they should be placed in the vicinity of the plastic access ports for the ama attachment bolts, or just slightly inboard of those ports. The fiberglass in that beam-end attachment area is solid and thick (strong), so the backing bar that usually comes with U-bolts should be positioned inside the beam, between the U-bolt-heads, and that should be adequate to spread the bolt load.

I used 6mm 1x19 stainless wire, with conventional rigging fittings. The US equivalent is 1/4" wire. I used a conventional fork fitting at the bow with clevis and cotter pins. At the beam end I used a turnbuckle (to allow fine adjustment) and snap-shackle. The type of pelican hooks used in lifelines would be better, and an alternative material to wire rope would be Dyneema or Spectra line. Of course, you should do your own research and evaluation of materials to be sure they will be strong enough, and make sure it is very low-stretch and you have a way to make fine adjustments. Tension should be low enough to enable you to detach the safety stay easily when you need it out of the way for folding or to pick up a mooring, but tight enough so the amas cannot move aft more than a ~centimeter in the event the folding cable mechanism fails.

My disclaimer is that all of the above advice is "home-grown" engineering. I think it was strong enough but it was never tested because I never had a folding system failure. My "standard" was to use materials and fittings that are at least as strong as Quorning used in the primary folding mechanism.

Larry
Great stuf again most helpful. I have a 920 with factory fitted bowsprit fitting so the same apllies for the strength of the fitting I would think.

Have you or anyone ( Factory?) considered a stronger strut that could be tensioned against the rear ama to hold the rear arm fully in place?

I would like to hear what the factory ideas of this thread are, do you have any contacts there ?

[buckle.roger]

Thanks again Larry, I sail in the Mediteranian and get a short nasy sea often with little wind so this issue of the for and aft movment of the amas is important to me. Can you give more details on the forward stay modification and again how much tension to put into it,
My fix to the oval holes in the struts was to turn them 90 degs and re drill the holes, wont stop it happening again but is better than nothing

Roger if you have the 1000 with bowsprit the forward attachment point is easy: You should remove a 10mm bolt on each side of the sprit (the one that bolts the sprit to the hull) and replace it with a 10mm eye-bolt (3/8" is also a suitable replacement for 10mm, they are almost exactly the same size). I used the aft-most bolt for Symmetri, but I recommend to use the bolt ahead of that so the wire safety stay doesn't interfere with an anchor or mooring line to the bow cleat. If you don't have a factory-installed sprit you will have a bigger job, because you cannot simply drill the fiberglass there (it won't be strong enough) -- you will need to reinforce the areas on each side of the bow with solid fiberglass and a backing plate to spread the load, then drill for the eye-bolt.

The boat should be fitted to a heavy U-bolt on the forward facing side of the outer end each front cross-beam. Newer boats were provided with those U-bolts from the factory, but if you need to install them they should be placed in the vicinity of the plastic access ports for the ama attachment bolts, or just slightly inboard of those ports. The fiberglass in that beam-end attachment area is solid and thick (strong), so the backing bar that usually comes with U-bolts should be positioned inside the beam, between the U-bolt-heads, and that should be adequate to spread the bolt load.

I used 6mm 1x19 stainless wire, with conventional rigging fittings. The US equivalent is 1/4" wire. I used a conventional fork fitting at the bow with clevis and cotter pins. At the beam end I used a turnbuckle (to allow fine adjustment) and snap-shackle. The type of pelican hooks used in lifelines would be better, and an alternative material to wire rope would be Dyneema or Spectra line. Of course, you should do your own research and evaluation of materials to be sure they will be strong enough, and make sure it is very low-stretch and you have a way to make fine adjustments. Tension should be low enough to enable you to detach the safety stay easily when you need it out of the way for folding or to pick up a mooring, but tight enough so the amas cannot move aft more than a ~centimeter in the event the folding cable mechanism fails.

My disclaimer is that all of the above advice is "home-grown" engineering. I think it was strong enough but it was never tested because I never had a folding system failure. My "standard" was to use materials and fittings that are at least as strong as Quorning used in the primary folding mechanism.

Larry
Great stuf again most helpful. I have a 920 with factory fitted bowsprit fitting so the same apllies for the strength of the fitting I would think.

Have you or anyone ( Factory?) considered a stronger strut that could be tensioned against the rear ama to hold the rear arm fully in place?

I would like to hear what the factory ideas of this thread are, do you have any contacts there ?

Can I sugest that this line of thought be followed in the Gerneral heading under HULL as it is generic to all DF,s

I have to fold mt DF 920 every trip so a line to both bows and tensioned is a bit of a pain, Can anyone see any reason not to use a similar arrangement but from the outer end of the aft arm to the inner end of the forard arm, this could be rigged at sea easily if and when the sea/wind required it ?

Secondly no one has answered the issuse on for and aft movment of the arms, they bang back on the saftey struts even when sailing in light winds and hitting a wake, no wonder the aloy saftey tubes get oval holes, Surely the saftey tubes should be stronger, reinforeced holes or stainless,
Even a screw arrangement to put tension on the rear of the aft arm to hold it firmly, anyone see any problems with this ?

[Double Horizon]

I have to fold mt DF 920 every trip so a line to both bows and tensioned is a bit of a pain, Can anyone see any reason not to use a similar arrangement but from the outer end of the aft arm to the inner end of the forard arm, this could be rigged at sea easily if and when the sea/wind required it ?

Secondly no one has answered the issuse on for and aft movment of the arms, they bang back on the saftey struts even when sailing in light winds and hitting a wake, no wonder the aloy saftey tubes get oval holes, Surely the saftey tubes should be stronger, reinforeced holes or stainless,
Even a screw arrangement to put tension on the rear of the aft arm to hold it firmly, anyone see any problems with this ?

If your nets are tight the amas should not have any aft movement.

As for using a safety stay attached between the forward beam base and outer aft beam -- it would surely work but an issue would be that it would become a trip-wire for any crew walking on the nets.

[Ipe Piccardt Brouwer]

I agree with Larry: in normal use, the beam should not hit back on the strut. It might happen in a heavy seaway (though I never noticed). No oval strutholes on my 10 years old DF920.

Might it be that your swingwingline is of the stretching type? Manual suggests using Spectra.

[buckle.roger]

I agree with Larry: in normal use, the beam should not hit back on the strut. It might happen in a heavy seaway (though I never noticed). No oval strutholes on my 10 years old DF920.

Might it be that your swingwingline is of the stretching type? Manual suggests using Spectra.

THanks gents. I would like to think that the arms will not hit the struts but several people seem to have this problem, I have 8mm pale blue lines which are very hard and stiff so i assume them to be spectra?????
I wonder if the jammers are slipping ? i will try marking the line at the jammer to see and also keep it on a winch to see if this makes any difference ?

[Jacob Blom]

I agree with Larry: in normal use, the beam should not hit back on the strut. It might happen in a heavy seaway (though I never noticed). No oval strutholes on my 10 years old DF920.

Might it be that your swingwingline is of the stretching type? Manual suggests using Spectra.

We sail a 2006 DF 920 touring and noticed that in a choppy sea, the leeward hull moved a little backwards when she hits a wave. The aluminium strut is only a safety device and also gives the exact position for fixing the swing-wing system. In my opinion the movement is possible because the curved side of the trampoline will stretch a little bit when the stealcable in the trampoline is tensioned when the speed decreases in a wave. Although this movement is normal, we didn’t like it and mounted the same stealcable from bow to forward beamend, that is standard on the Extreme. We are very statified; now there is no movement at all!

Jacob Blom

[buckle.roger]

I have to fold mt DF 920 every trip so a line to both bows and tensioned is a bit of a pain, Can anyone see any reason not to use a similar arrangement but from the outer end of the aft arm to the inner end of the forard arm, this could be rigged at sea easily if and when the sea/wind required it ?

Secondly no one has answered the issuse on for and aft movment of the arms, they bang back on the saftey struts even when sailing in light winds and hitting a wake, no wonder the aloy saftey tubes get oval holes, Surely the saftey tubes should be stronger, reinforeced holes or stainless,
Even a screw arrangement to put tension on the rear of the aft arm to hold it firmly, anyone see any problems with this ?

If your nets are tight the amas should not have any aft movement.

As for using a safety stay attached between the forward beam base and outer aft beam -- it would surely work but an issue would be that it would become a trip-wire for any crew walking on the nets.

I realise your point re it being a trip wire but it is the only way I can see of being able to add stiffness when at sea if it get rough as the bow line would not be much fun to fit at sea,

[Double Horizon]

I realise your point re it being a trip wire but it is the only way I can see of being able to add stiffness when at sea if it get rough as the bow line would not be much fun to fit at sea,

You would not fit the bow safety stay at sea. It should be fitted every time you unfold the boat, so you would do it in sheltered water before you leave the harbor. When the boat is open the stays are always attached. These stays are back-up in case of a failure of the folding lines/cables and clutches, and are not needed to add "stiffness" if your primary folding lines are functioning properly. (Think of it like using a safety belt in your car -- if you don't have it on in-advance of a problem, you won't have time to put it on when you need it.) The only time you might remove them (when open) would be when you want to anchor or pick up a mooring, if the placement interferes with line handling from the bow. Those situations would also be in protected or calm water.

Also, you should make the bow attachment "fixed" with clevis pin and cotter pin/ring, and make the removable shackle end at the beam-end, so you are walking on the front of the nets when you need to attach/remove the stays. When the stays are removed they can be attached to the forward end of the cabin-top rails, to keep them out of the water.

[buckle.roger]

I realise your point re it being a trip wire but it is the only way I can see of being able to add stiffness when at sea if it get rough as the bow line would not be much fun to fit at sea,

You would not fit the bow safety stay at sea. It should be fitted every time you unfold the boat, so you would do it in sheltered water before you leave the harbor. When the boat is open the stays are always attached. These stays are back-up in case of a failure of the folding lines/cables and clutches, and are not needed to add "stiffness" if your primary folding lines are functioning properly. (Think of it like using a safety belt in your car -- if you don't have it on in-advance of a problem, you won't have time to put it on when you need it.) The only time you might remove them (when open) would be when you want to anchor or pick up a mooring, if the placement interferes with line handling from the bow. Those situations would also be in protected or calm water.

Also, you should make the bow attachment "fixed" with clevis pin and cotter pin/ring, and make the removable shackle end at the beam-end, so you are walking on the front of the nets when you need to attach/remove the stays. When the stays are removed they can be attached to the forward end of the cabin-top rails, to keep them out of the water.[/quote


Thanks again for your input, all good points. But if bo is momitoring this link it would be greatr to here what the factory say on this important subgect of for and aft movment of the amas!!!! I know this has been said before but so far no responce.

Thanks for the web site and people who input toi it

[Bo Wetzel]

Well Roger, I'm 'monitoring' this subject as well as all others.

Unfortunately, I've no direct contact to the factory. However, I've sent some 2 weeks ago an email to Jens to ask for his advice on this matter but have not seen a response. He is probably too busy building DF35s

I will send another email to Jens to ask for his comments. I will also contact Arne Reher again to get his comments on the 'correct' setup of the swingwing system.

[buckle.roger]

I have just had a very unexpected phone call from Arnie, he has picked up on this thread re movment of the amas when sailing hard into a sea at speed, he is up at the factory latter this month and will try and sort out the answers from them whilst there, he will post the result here.
I thank Arnie for picking up on this

[Bo Wetzel]

Hello Roger

Just a small point, his name is Arne and not Arnie.

I'm pleased that my prodding has helped.