In-Mast Furling Mainsail+ Topping Lift+ Rigid Boom Vang?

[Bob 04 H260]

Newer Hunters with a "rigid" vang usually have the Selden Rodkickers installed. Selden says they should never be adjusted so they bottom out, they seem to be well damped and with the vang, topping lift, and short mainsheet from the end of the boom to the arch so the boom seems contained pretty well.

As far as the boom touching the arch, if the sail is all the way up the mast and the boom touches the arch or the bimini then the sail is either stretched or not properly cut. Company's like Hunter, UK and Doyle do not put boats and sails together that are not designed to be adjusted properly.

I know there was a problem with sail cut on early 356's so that there was leach flutter on the mainsail, UK fixed the problem quickly.

It seems to me if you can't flatten the mainsail then the sail needs to be fixed, the boat does not need to be redesigned.
Bob

 

[Nodak7]

Newer Hunters with a "rigid" vang usually have the Selden Rodkickers installed. Selden says they should never be adjusted so they bottom out, they seem to be well damped and with the vang, topping lift, and short mainsheet from the end of the boom to the arch so the boom seems contained pretty well.

As far as the boom touching the arch, if the sail is all the way up the mast and the boom touches the arch or the bimini then the sail is either stretched or not properly cut. Company's like Hunter, UK and Doyle do not put boats and sails together that are not designed to be adjusted properly.

Bob

Bob, If what you say is correct when I have my sail completely deployed, the main halyard up completely, the traveler centered and the mainsheet completely retracted my main would be flat and tight. I have found that not to be the case in either of my boats. This is my second Hunter the first being brand new and the second with a nearly new (lightly used) main. There is always some draft in the sail when rigged as such. Note the draft in the mainsail on the picture attached. As you can see if I could adjust the vang (collapse it further) I could flatten and tighten the main but as you see that would create interference with the arch and bimini. Are you saying that both these "new" sails are cut improperly? Anyway when I need my sail flattened further I just retract some sail into the mast. Much easier than messing with the vang. :dance: True?

One further note. If you look at the vang position on these long booms and large sails I am not certain that I have enough mechanical advantage to even pull the boom down to flatten the sail when there is any kind of wind blowing. It is set so far foward. I believe it should be lengthened but that is another story.

Additionally, I need to go back into my documentation to find the Selden reference you mention regarding the rodkicker. I do not recall it. The first one I purchased came set up with the rodkicker completely collapsed from the dealer. Unfortunately there are only two boats (one of which being mine) on our lake that have furling mains so I cannot survey how others have theirs adjusted but I as soon as I get where there are more boats I will make a note of how they have theirs adjusted.

 

[Bob 04 H260]

Nodak, I am no expert on sail controls or inmast furlng. You are probably right. These are just my experiences and observations on the subject.

The Selden manuals are all available on line, I got this from the RodKicker manual,

B. Fitting the Rodkicker
1. Fit the boom-slider so that it is moveable along the
boom. If the boom has a fitting that cannot be moved,
great care must be taken to avoid damaging the Rodkicker
when executing point B3 below. The length of
the Rodkicker in its compressed state can be altered by
shortening or replacing the larger tube. Contact your
dealer.
2. Fit the Rodkicker to the boom and the mast fittings. Ensure
that the boom slider can slide so that the Rodkicker
is not subjected to any compression forces during point
B3 below.
3. Keep the boom in the position achieved in B3, compress
the Rodkicker with it´s tackle until the upper fitting just
contacts the upper bushing. If a gas cylinder is fitted, a
force of between 600–5000 N (60–500 kg) is required
depending upon which cylinder is fitted.
4. Hoist the mainsail, and sheet home hard whilst ensuring
that the Rodkicker does not ”bottom”.

Any of the boats I have owned did not have enough advantage to pull the boom down with the vang in the situation you picture. I would normally use the vang to keep the boom down only when well off the traveller, i.e. when on a run. Otherwise I would use the mainsheet and the outhaul to flatten the sail. In other words I do not use the vang to flatten the sail as I usually don't want to flatten the mainsail when sailing down wind. (If I'm doing something wrong I'm very open to learning how to do it right.)

I have been on other Hunters and Beneteaus with inmast furling and not seen an issue with being able to flatten the sail with the mainsheet and outhaul. Rolling in a bit of sail on the furler is a smart trick and would work as well....certainly easier than redesigning the boat.

I notice that most of the boats I see with inmast furling have the boom aft end sitting quite high, surprised some have a problems with it contacting the bimini or arch.

If I could not flatten a new sail using the mainsheet and outhaul I would ask the builder to look at how the sail was cut and I would expect it to be fixed. I think Selden specifies a new mainsail be cut at an 85* angle between the luff and the foot, I would check that first myself.

Thanks for the information, perhaps we should be asking this in the Hunterowners forum to see how other Hunter owners with inmast trim their mainsail ?

regards, Bob

 

[Nodak7]

4. Hoist the mainsail, and sheet home hard whilst ensuring
that the Rodkicker does not ”bottom”.

Any of the boats I have owned did not have enough advantage to pull the boom down with the vang in the situation you picture. I would normally use the vang to keep the boom down only when well off the traveller, i.e. when on a run. Otherwise I would use the mainsheet and the outhaul to flatten the sail. In other words I do not use the vang to flatten the sail as I usually don't want to flatten the mainsail when sailing down wind. (If I'm doing something wrong I'm very open to learning how to do it right.)

I have been on other Hunters and Beneteaus with inmast furling and not seen an issue with being able to flatten the sail with the mainsheet and outhaul. Rolling in a bit of sail on the furler is a smart trick and would work as well....certainly easier than redesigning the boat.

I notice that most of the boats I see with inmast furling have the boom aft end sitting quite high, surprised some have a problems with it contacting the bimini or arch.

If I could not flatten a new sail using the mainsheet and outhaul I would ask the builder to look at how the sail was cut and I would expect it to be fixed. I think Selden specifies a new mainsail be cut at an 85* angle between the luff and the foot, I would check that first myself.

Thanks for the information, perhaps we should be asking this in the Hunterowners forum to see how other Hunter owners with inmast trim their mainsail ?

regards, Bob

Bob, I am by far no expert on this and all I can do is speak from experience. Much of which could be worthless to anyone else but me.

Thanks for looking that up in the manuals and I understand exactly what they are saying. If the rodkicker is allowed to bottom out and you continue to pull down on the sheet you could do what I was suggesting in my first not and end up leveraging and potentially damaging the boom. However, this is a "lose/lose" situation for a furling main system. If you leave the rodkicker with some play you can "mess" with the angle of the boom and interfer with the furling of main. If you leave no play in the rodkicker you can potentially hurt the boom. I guess I have chosen the second since I do not want to mess with the furling of my mainsail in any way. Again as I stated earlier I have my vang adjusted so it is collapsed when the traveler is centered and the mainsheet is pulled in all the way to the pulleys. This insures that I cannot over leverage the boom. Point in fact I doubt I mess with the vang more than once or twice per season. As I said when I want to flatten my mainsail I just furl it in until it is as flat as I want it to be.

My boom does sit high as well. I always attributed that to the cut of the sail. It definitely does not run parallel to the boat.

Nodak7

 

[Nodak7]

Nodak7

Don,

After my conversation with Bob, above, it got me thinking about sail trim with a furling mainsail (in-mast specifically). By the end of our conversation I began to wonder if a Vang really is necessary on a furling main sail.

So Don here is my question to you.... regarding sail trim

Here is my hypothesis
After thinking about how the vang works, or does not work, on a furling mainsail I began to wonder whether it was really necessary and could be replaced with a solid piece. I came to the conclusion that it can be and my conclusion is based on the fact that they are really only needed to hold the boom up and away from the bimini (and in the case of the Hunter the arch). Here is why.... if I want more draft in my mainsail I only need to loosen the outhaul and can get as much draft as I desire. Likewise if I want my mainsail flat I need only to furl in the main until I have attained the flatness I desire. Does that not do what the Vang is supposed to do in regards to sail trim? I would like you to please tell me if I am correct or misguided.

Waiting with baited breath on your reply....

 

[capta]

sheet to arch

I cannot imagine the forces at work when you take a main sheet on a 35 to 40+ foot boat to a fiberglass arch. Add a boat manufacturer that has a reputation for less than stellar quality, gale force winds (or more) and a need to claw your boat off a lee shore to save her and yourself. Isn't there a lot of flex in the arch when under load? Can the arch possibly have sufficient strength where it attaches to the deck/hull for sailing in life threatening conditions?
I have been forced to sail in 100+ knots of wind and even though that boat was 65 years old, she did as asked and got us home safely. The gear was a tad stressed, I might add.
And lastly, why not have the main recut to fit the configuration the arch requires, rather than sail with a poorly set sail? Then you'd never have to worry about the boom hitting the arch!

 

[Barnacle Bill]

I said "if" the arch gets in the way of mainsail trim, then it is a bad idea. I don't know if it does, but made that comment because an earlier comment that suggested it might. If it doesn't, so be it. Lighten up a bit. I'm only trying to make useful suggestions.

 

[Nodak7]

I cannot imagine the forces at work when you take a main sheet on a 35 to 40+ foot boat to a fiberglass arch. Add a boat manufacturer that has a reputation for less than stellar quality, gale force winds (or more) and a need to claw your boat off a lee shore to save her and yourself. Isn't there a lot of flex in the arch when under load? Can the arch possibly have sufficient strength where it attaches to the deck/hull for sailing in life threatening conditions?
I have been forced to sail in 100+ knots of wind and even though that boat was 65 years old, she did as asked and got us home safely. The gear was a tad stressed, I might add.
And lastly, why not have the main recut to fit the configuration the arch requires, rather than sail with a poorly set sail? Then you'd never have to worry about the boom hitting the arch!

Capta, actually Hunter has not put a fiberglass arch on their boat for quite some time. They are all ss tubing now and very sturdy. I have never felt concern about it struturally and have had it out in very high winds (40+ kts) with lots of force on it. I would not want to be out in 100 kts winds and I definitely would not want to have sails up in those conditions. BTW we attended the Annapolis boat show and toured 30+ boats and I would have no hesitation to compare the build on Hunte boats to any that we saw there in the mid range boats. For the money I do not believe you can beat a Hunter. IMHO :dance: I know that I for one would never be able to afford the price of a comparable sized boat. There is no doubt it is a Chevy and not a Rolls!

However to answer your question regarding the sail cut. I guess that I could have it recut regarding the potential for hitting the arch and that probably would be the ultimate solution for that issue. But, I believe, I can set the sail properly using the tools that I have. I really do not have an issue with getting it set right it is just a different methodology using a furling main.

Just curious... how the heck were you ever out in 100kts winds? :wow: I shudder to think about it. The worst that I have been in is 60 kts and that was way more than enough for me!

 

[Nodak7]

I said "if" the arch gets in the way of mainsail trim, then it is a bad idea. I don't know if it does, but made that comment because an earlier comment that suggested it might. If it doesn't, so be it. Lighten up a bit. I'm only trying to make useful suggestions.

It can if the Vang is not adjusted properly Barnacle. Mine is adjusted so it will not. I really was teasing you so I apologize if I wrote it the wrong way.

 

[Bowedtoothdoc]

Not to start a war here, but the arches on the larger Hunter boats are plenty strong and most of these are made of extremely thick stainless steel tubing. They only made fiberglass arches for a short time. Also the attachment point is on the rear of the boom...I would bet you that the forces on the cabin top traveler on my old 34 ft boat were much greater than my Hunter 450. Also anyone going off shore should know their boat enough to know when and how to reef their sails...Thus not over powering the boat or any of the rigging.
On the larger Hunters like mine and Nodak's the vang is useful for shaping the sail for reaching and running. Because of the B&R rig she will not sail DDW with out a true spinnaker, but the vang can be helpful for shaping the main on a close reach to a broad reach. When beating the main sheet is tightened down so that the vang is almost bottomed out and I use the traveler to control the angle of the main. At no time does the arch get in the way.

 

[Bob 04 H260]

I agree that the mainsheet loads are not that big. No need to imagine them, easy enough to calculate or look at the ratings on the blocks used on the mainsheet.

I think everyone would agree the Hunter boats are not designed to be sailed in 100+kts winds. If they were they would not be much fun to sail in the 15 to 20 kts that most of us like to sail in.

Hunter say they have never had an arch failure. The stainless steel arch is through bolted with 3/8" aluminum plates glassed into the deck.

I see other makes of sailboats that have had an arch fabricated and put on them so Hunter must be doing something other sailors like.

Even some of Hunters competitors are adding arches on the newer higher end models. I guess that will cause even more confusion for the experts.

Bob