Improving the Hunter 216

Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
I just purchased a 2008 Hunter 216. It was only sailed ten times in ten years but it needs a good deal of upgrades. First major upgrade should be sails as the original equipment main looks weak fifteen years out from the launch of the boat.

I would like to first start a good, wide-ranging discussion on the best attributes of the rig/hull combination of the Hunter 216 and what sails might work the best for our boats. I have a racing/performance interest however most ideas should be transferable to the day-sailors among us. If we establish basic upgrades I am sure we can contact hardware manufactures and sail lofts and receive reasonable bids on purchasing multiple sails, and hardware with written directions to upgrade our boats..

I will start the conversation rolling, if I may, with what might be beneficial for enhancing the most amount of "fun" out of our boats:

Because our designer dispensed with the fixed backstay we are in the enviable position to add Roach to the sail and run square head, or square top mains. In their book, The Art and Science of Sails, Authors Tom Whidden and Michael Levitt point out that the most inefficient profile for a sail is a triangle! Guess what most pin-head mainsails resemble? Yes, triangles! The authors conclude that a U-shape is much more efficient, that is why square-top mainsails are used in America's Cup beause they produce more lift! We have that great opportunity to design, build, and deploy the best ideas of the day into our new suite of sails.

A few Mainsail ideas to improve performance:

1.) Square-top or Fat-head
2.) Extended Leech
3.) Laminate or fabric that allows the designer to build panels that radiate from the head, luff, tack and clew.
4.) Multiple battens, with two full-length battens high and standard battens low, to help flow.
5.) Moderate foot depth (that give us more ability to manipulate sail shape) that should produce more power.

6.) Possibly designing a new rolling jib to match the higher preforming main.

Sail fast,

John
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
John

I’m hoping this thread can become a collection of Best Practices for improving performance of the 216. Thanks for starting it!

I would point out that the “redesigned” 216 which Hunter named the Hunter 22-2 or H22 or Hunter 22 which quite frankly causes a lot of confusion as they already have a pocket cruiser with the same name has as one of the improvements a larger main so I think your jumping off point is appropriate as imho the big roachy main is where a large percentage of the power comes from on this model.

This is a photo I snagged off the Marlow-Hunter 22 advertising page.

08556FC7-80B2-4D88-9713-93112A2165E5.jpeg
 
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Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
Hunter216,
Best Practices for improving performance of the 216 it is!!

BTW, that is what we should be looking at for a modern mainsail!

Sail fast,

John
 
Sep 22, 2018
1,869
Hunter 216 Kingston
Hunter216,
Best Practices for improving performance of the 216 it is!!

BTW, that is what we should be looking at for a modern mainsail!

Sail fast,

John
Here is another screen grab of the same H22-2 boat showing the main in full action. Also note the traveller and retractable bowsprit for the spin.

Traveller plus bowsprit and spin.jpg
 
Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
Hunter216,
Take a good look at the end of the retractable bowsprit for the spinnaker. Is that a roller?

I know because of our fractional rig with no backstay that we will have to develop a bowspirt system and incorporate an asymmetrical spinnaker. But I never thought about utilizing a roller!
Sail fast,
John
 
Sep 22, 2018
1,869
Hunter 216 Kingston
Interesting article comparing square and pin headed mainsails

Source

Page doesn't exist


Head Affair: Squaretop vs. Pinhead Mainsail
28 Feb 16:16
The German magazine "YACHT" published an article in collaboration with SAPHIRE about the different types of mainsails. I like to follow up on this topic in English language, knowing that English is not my native language. The article is based on my own experience since we use both sails on our Saphire 27 and could gain some good impressions about the potential and differences.
The facts:
Squaretop mainsail, 29m2 on a Carbon mast, Pinhead mainsail 22m2 on an Aluminium mast. Same rig dimensions. Weight of the SPORT version 1341kg with electric engine. Weight of the CRUISE version 1540kg with outboard engine, both versions equipped with the performance keel:
FM27 Sport

But first some theory
  • Aerodynamic propulsive force
    Is being created due to different static pressures as a consequence of the different flow rates (wing profile)
  • Parasitic resistance
    Form drag and frictional resistance are given facts due to the objects in our living environment (mast; sails, hull etc.)

  • Induced resistance
    Loss of kinetic energy as a result of the curling of an edge vortex at the trailing edge. Is caused by the pressure compensation in lee and windward (lateral forces)
    • The kinetic energy - also called velocity energy - is the energy that an object receives due to its velocity
    • The induced resistance is reducible in magnitude and can theoretically be brought to zero
    • The simplest way to reduce the induced resistance is to extend the wing span
  • Laminar flow
    Adherence of the flow, i.g. if the individual fluid particles move in an orderly manner, one recognizes the tell tails in the headsail and the leech on parallel paths

  • Turbulent flow
    The fluid particles whirl around without order and cohesion

  • To sail fast means:
    A maximum of propulsive force (surface), a minium of resistance (parasitic and induced) and a laminar flow of the wind on the sail.
Experiences on the A-Class catamaran





The A-Catamaran is a open design class, founded in 1956 by the then YRU and has continued to evolve. Many famous sailors such as Dean Barker, Glen Ashby, Bill Slingsby and many others had been using the A-Class catamarans for many years as a training tool.
Before the year 2000, no Squaretop sails were used but the masts were built ever higher with classical sails. At that time over 10.5m high with Pinhead sails while the sails shown here use all masts around the 9.0m. However, the shape has evolved from a slightly flared to a more flared (top > 50% of the foot) and back again. The reason being the higher speed of the foiling boats, which is why the sails are cut down to the trampoline and a surf boom is being used to lower the centre of gravity.

Practice - how does a Squaretop mainsail work?
Trim of the mainsail at the A-Catamaran
A lot of cunningham is being applied, boom close to the centreline, sheet tension just as strong that the desired effect in the upper part of the sail arises, e.g. inverted or with open leech.
Result
In strong winds the upper part of the sail inverts and creates a righting moment!
The A-Catamaran sails 12.5 - 13kn upwinds and as soon as the sail inverts in the upper part, an enormous acceleration effect is created and the boat reaches 13.5 to 14kn upwind (without foililng).

The parasitic resistance remains the same, the induced resistance decreases because the flow is laminar and creates a righting moment from leewards. The entire sail area is used and the edge vortex arises only along the horizontal edge of the sail. If the upper part of the sail is only "emptied", more induced resistance arises, i.g. the edge vortex rolls up and pulls down the leech, the current becomes turbulent. In the following picture you can clearly see that the entire upper part of the sail is inverted and the tell tails are perfectly aligned (laminar flow).

With proper trim you can do without a reef. With the A-Catamaran, there is no reefing function. The helmsman stands already in trapeze at force 1.5 and can still manage to keep the boat with the same righting moment even at force 6 at much higher speed, even though he sails with the same body weight. This can only be achieved by trimming and precise control of the sail. If the sail had full pressure, the A-Catamaran would capsize immediately.


Upwind trim possibilities with a Squartop mainsail
In the picture on the right, there is more wind, the boom is slightly windward, the vang relatively loose and the sail twists enormously, means it opens up completely. There is not enough wind to invert it yet. However, with a small crew, very tight upwind angles can be sailed because the lift is produced by the centred boom position while the middle part of the sail generates propulsion. All tell tails along the leech point to the rear and the boat sails very fast.
In the picture on the left there is less wind, the boom is tighter and on the centreline, while the pressure point of the sail is shifted upwards. This allows you to produce as much pressure in less wind as in the picture on the right. In this case, the boat is not only fast, but reaches very tight upwind angles.

Inverted mainsail
Here, just after the tack, the profile is inverted from the top to the bottom, depending on how much sheet tension you give.

Advantage: the sail never flaps, is always still, the flow is not interrupted, no vibrations and a good righting moment in the top of the mast/sail

• In strong winds, the sail can be used in this way, instead of using a reef
• The induced resistance decreases with increased propulsion

Disadvantage: less sheet tension and thus less tension on the forestay - a drag can arise, because the forestay has too little tension. This could be corrected with backstays, but that makes the boat too complicated and the loss of performance is in the lowest percentage range.

Uwpind wind trim of different mainsails
Clear differences in trim can be seen in the following picture:
Squartop
The squaretop has a so-called straight open leech and can never be closed.
Trim: boom on the centreline, vang prety open, cunningham tight, mainsail open at the top
Pinhead
The Pinhead mainsail has a so-called round, closed leech and the biggest danger is to overlap or close it. In this case, the upper part of the sail closes and produces significant turbulence.

Trim: boom more leewards, vang tight, more sheet tension, leech closed
Comparison
The Squaretop mainsail allows you to sail closer upwind angles in these conditions, while from about 12 to 13kn of wind, the boats sail the same speed and angles. From about 16-18kn wind the Pinhead sails closer upwind angles and the Squartop a little faster. Reason: SQTOP generates less tension on the forestay and the jib starts producing some drag.

Both sails can be set on the carbon as on the aluminum rig. The weight difference of the masts is 12kg, the stiffness is similar. Of course you can tune the carbon masts a bit better in view of the characteristics of the square-top sail, but the differences are not significant and are only perceived in hard racing.

Vortex drag
(Graphic design from YACHT Germany, edition Nr. 21, 2016)

Downwind comparison
The Squartop mainsail is always faster - in all conditions - except in tight reaching angles and strong winds
The vang always remains prety lose and open so that the sail can twist a maximum.
The boom is to be kept not too far leewards. The sail twists in the upper part. The acceleration comes from the middle part of the sail and in the upper part you control the Vortex drag with the tell tails what can be seen on the picture.
Very important is to lose the vang when jibing otherwise you risk to broach.

Helming the boat with a squaretop mainsail
Wrong is the general statement that a Squaretop sail creates more rudder pressure: Due to the straight, open cut and the overall much flatter profile the Squaretop produces no more rudder pressure than the classic mainsail - there is one exception, however: At force 2 the sheet can be so close hauled and the pressure point of the sail so far moved up that in fact pressure on the tiller arises - wanted! Because with these conditions you can then put five people windward and the wind pressure drives the boat at a very tight upwind angle - much tighter than any classic mainsail. As soon as the wind rises, the mainsheet is realeased centimeter by centimeter and at the same time the rudder pressure is reduced and the propulsion increases - exactly what these sails like most!

Square Top sails require more attention of a helmsman. It has been shown that the maximum size of the top should be less than 50% of the foot, so that it can a) be cut well and b) have a good profile. In addition, the use of modern laminates or membran sails present a significant advantage, especially for larger areas.

The helmsman must always helm exactly at the edge of the wind, take advantage of every gust and work with the mainsheet and the traveler continuously. These sails offers a variety of options in all wind conditions, while the classic mainsail is easier to handle and can also be used without a mainshee traveler rail.

Of course, a square top sail brings more fun, but it is aimed at an ambitious sailor who always wants to get the maximum out in all wind conditions, while the classic mainsail forgives much - even steering errors - and thus clearly cruising is the right choice for this sail.
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
Hunter216,
Take a good look at the end of the retractable bowsprit for the spinnaker. Is that a roller?

I know because of our fractional rig with no backstay that we will have to develop a bowspirt system and incorporate an asymmetrical spinnaker. But I never thought about utilizing a roller!
Sail fast,
John
Certainly looks like a roller furler for the spin. The stock retractable sprit on the 216 is mounted on the top of the foredeck while the one on the H22-2 exits the bow from inside. I don’t know what effect adding the roller to the end of the tube would have on the 216?
 
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Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
Certainly looks like a roller furler for the spin. The stock retractable sprit on the 216 is mounted on the top of the foredeck while the one on the H22-2 exits the bow from inside. I don’t know what effect adding the roller to the end of the tube would have on the 216?
Group,
Who has experience sailing an asymmetrical spinnaker with a roller at the end of the sprit?
Sail fast,
John
 
Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
Interesting article comparing square and pin headed mainsails

Source

Page doesn't exist


Head Affair: Squaretop vs. Pinhead Mainsail
28 Feb 16:16
The German magazine "YACHT" published an article in collaboration with SAPHIRE about the different types of mainsails. I like to follow up on this topic in English language, knowing that English is not my native language. The article is based on my own experience since we use both sails on our Saphire 27 and could gain some good impressions about the potential and differences.

Great article Hunter216!
John
 
Sep 22, 2018
1,869
Hunter 216 Kingston
This is a photo of my stock 216 main hoisted. I was trying to think of a way to determine this exact location (can’t climb the mast) and mark it so that anyone hoisting the sail can determine its all the way up.

4CA73558-FC69-45D7-A427-B51B3D22AF36.jpeg
 
Apr 16, 2017
841
Federation NCC-1701 Riverside
Nice thread! Square top mains allow more twist and that reduces stalls since at least some section of the wing is lifting. The problem is the twist also means the boom needs more 3 dimensional control that entry level boats dont have. First checklist item is a traveler. Without having a traveler and the will to figure out what it does to the boom, square tops are almost useless.

My entry level boat doesnt have a traveler and is midboom sheeted so its very hard to have twist on my triangular sail. I saw a need for this twist while out and was saddened that the only way for my boat to have twist under pressure was to use the topping lift to slop off the leach tension. I could tben have equalized the vang and adjusted AOA with the mainsheet.

Traveler would have been nice.
 
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Sep 22, 2018
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Nice thread! Square top mains allow more twist and that reduces stalls since at least some section of the wing is lifting. The problem is the twist also means the boom needs more 3 dimensional control that entry level boats dont have. First checklist item is a traveler. Without having a traveler and the will to figure out what it does to the boom, square tops are almost useless.

My entry level boat doesnt have a traveler and is midboom sheeted so its very hard to have twist on my triangular sail. I saw a need for this twist while out and was saddened that the only way for my boat to have twist under pressure was to use the topping lift to slop off the leach tension. I could tben have equalized the vang and adjusted AOA with the mainsheet.

Traveler would have been nice.
I’ve been wishing I had a traveller on the 216 but don’t want to give up the more important value (to me anyway) of the open cockpit and open transom, the main reasons I chose this boat in the first place.

I really appreciated the performance and safety gains a traveller added to other boats I have owned but for some reason I found myself or more often my passengers getting tangled up or banging shins etc. so wouldn’t mount a traditional bar across the seats. I’m not sure the structure of the 216 would handle that very well anyway. I know the H22-2 has a traditional traveller bar as an option but I’m pretty sure that when they switched to FRP from Luran they added a bulkhead under the seats to beef things up.

What would be ideal for me would be a system that could utilize the current main sheet system, quickly attach and detach, have the ability to revert to the current floor mount mainsheet location if desired and somehow not interfere with handling the outboard. The existing stern cleats would be a good hull connection point as they already exist and should be solid enough to not tear out. I can’t visualize a bridle system that would not get tangled up in the Vara rudder - tiller handle???
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
Since we started out talking mainsails I thought I would post my high wind solution.

As you likely know the 216 likes to be sailed flat but as wind strength increases and/or crew weight to aid in hiking is minimal there is a point where the stock main even reefed isn’t enough to sail the boat at optimal angles or even safely.

I was fortunate enough to buy the boat from someone who had invested in a main from a Hunter 146 that he used to learn how to sail the boat safely before he moved up to the stock main.

I always carry this sail on the boat as my “get home” rig but have tried it once in steady 20 gusting 30 conditions and even singlehanded found the boat much more comfortable to handle.

The photo below shows the boat with the sail up. I didn’t have the slug for the foot of the sail inserted in the boom so it looks weird but it gives you the idea. BTW the 146 has a reef so I could make it even smaller if I had to.

86B75398-BAD1-4169-9F5E-1C141D523925.jpeg
 
Apr 16, 2017
841
Federation NCC-1701 Riverside
Since we started out talking mainsails I thought I would post my high wind solution.

As you likely know the 216 likes to be sailed flat but as wind strength increases and/or crew weight to aid in hiking is minimal there is a point where the stock main even reefed isn’t enough to sail the boat at optimal angles or even safely.

I was fortunate enough to buy the boat from someone who had invested in a main from a Hunter 146 that he used to learn how to sail the boat safely before he moved up to the stock main.

I always carry this sail on the boat as my “get home” rig but have tried it once in steady 20 gusting 30 conditions and even singlehanded found the boat much more comfortable to handle.

The photo below shows the boat with the sail up. I didn’t have the slug for the foot of the sail inserted in the boom so it looks weird but it gives you the idea. BTW the 146 has a reef so I could make it even smaller if I had to.

View attachment 168726
Thats fantastic! I was thinking the same thing wirh my 170. Since I singlehand more often and reef most of the time i thought about trying out a 146 mainsail and even a 420 mainsail. I figured a 420 would be cheaper to since there us more volume, but nope, same price.
Great idea.
 
Sep 22, 2018
1,869
Hunter 216 Kingston
Thats fantastic! I was thinking the same thing wirh my 170. Since I singlehand more often and reef most of the time i thought about trying out a 146 mainsail and even a 420 mainsail. I figured a 420 would be cheaper to since there us more volume, but nope, same price.
Great idea.
When I was buying the boat I wondered what I would do with the 146 sail and considered selling it but then the lightbulb came on. I don’t tend to intentionally go out when I would need this sail but it was fun to experiment with. Biggest value to me is the get home insurance it provides. I would also consider using it if I was taking some young kids out for their first time sail, no “scary” stuff happening to turn them off.

I can relate to the modern vs older tech sails discussion from my windsurfing background. I started windsurfing on the original rig with teak booms, baggy sail etc (yes I’m that old ;) where the COE of the sail would change drastically and just SLAM you into the water, even worse as things evolved to harness lines causing you to tether ball before it slammed you!

First big evolution was a quiver of fully battened cambered sails that let you pick the sail size appropriate to the conditions you were heading out in. All good unless you over or under estimated the size of sail and had to come ashore (if you weren’t totally overpowered and needed rescuing!) Crashes were much less frequent as the sails held their shape and acted predictably.

The real improvement came when the sail designers were able to design in the ability for the sail to dynamically change shape without affecting the rider. Modern windsurfing sails have square tops and a head that twists off during a gust or increase in wind strength and the rider only feels an increase in speed - no extra effort to hold course etc. This allows the rider to select a sail size for the lulls they might encounter and if the wind builds have confidence that they won’t have to change rigs as the sails have a huge wind range compared to their predecessors

Here is the latest innovation and yes I have one. Note the 3.5m sail size difference with better planing performance!
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
This is a photo of my stock 216 main hoisted. I was trying to think of a way to determine this exact location (can’t climb the mast) and mark it so that anyone hoisting the sail can determine its all the way up.

View attachment 168700
I dropped my mast and was able to measure and mark both the reefed position and the fully all the up point.

Reefed is 39” and all the way up is 7 1/2” from the top of the mast extrusion to the top of the headboard.

35566A57-A7F6-41F9-B059-7771866BB759.jpeg




D2A4D583-CF0D-46DF-88C9-4EE396D39388.jpeg
 
Sep 22, 2018
1,869
Hunter 216 Kingston
I’m going to try to re-post @H216sailor post from another thread as it is applicable to this discussion:

Congratulations on your new boat! I personally like the muted, 100% balanced feel of the rudder on the 216, you just have to be careful because it won't give you the same feedback as an unbalanced dinghy rudder. I also plan on sailing the boat with a symmetrical spinnaker. It will be almost to the masthead (2' short of the top, 4' above the forestay tang). I will also be using running backstays to keep the rig up with that spinnaker up. I have done a few races in non-spinnaker class in moderate breeze and I've found that the boat does not like any heel upwind. None at all. The first race (picture below) I was sailing with two people and it was not enough weight on the rail. The second race had the same conditions and I sailed with three people and it felt a lot better.

Unfortunately by jib ripped apart in a storm a few weeks ago so I haven't had time to test the new spinnaker. I have the stock Dacron sails as well. I got a quite from a Loong Sails rep who is located in CT for a new laminate mainsail. I've attached the quotes below. I got two quotes: one for ZZ Black Polyester cloth and one for ZZ Black Aramid (Mylar) both from Contender sailcloth. The Polyester is cheaper as it has more stretch then the Mylar, but will probably last longer and would be fine for my purposes.

H10.jpg
 

Attachments

Nov 19, 2018
28
Hunter 216 Silver Lake, Wisconsin
Great research on mainsail.
I will also get quotes.
Below is the first simple modification I accomplished. The Hunter 216 mast bumper is key for upwind close hulled pointing as the side stay tension is relatively low (another tubing discussion). The 216 mast really moves around, so the rubber bumper helps position and also provides a fulcrum point for mast rake.
Because in rough water the pin could “walkout” of its eyes, drilling a through-hole at the end of the locating and installing a Wingding is cheap insurance!
Sail fast,
John
9386A08C-D66F-4277-A787-E55BE380D05A.jpeg