North Sails M-16 Scow Sail Trim
Knowledge is power. We see this in every sport throughout the world. Racing sailboats is much different from the other sporting events. Sailing requires tuning for different wind and water conditions. Many of these tuning adjustments are very small, yet critical.We have outlined for your information tuning information for many different boats that we race on a regular basis. The measurements achieved have been tested through countless hours on the water in a variety of conditions. What is truly unique with this booklet is the fact that we have simplified the tuning process for all of these classes in order to make the process easy for our customers. You will be able to achieve newfound speed in your class. These measurements coupled with the fastest one-design sails in the world will give you the knowledge for speed. In sailboat racing this is a combination for power and speed!
0 - 5 Knots
The first objective here is to get plenty of heel on the boat so the windward rudder is just out of the water. This will account for less surface area in the water and will make the boat go faster. The skipper and crew must sit very still on the boat so there is no disruption of wind in the sails. The skipper must steer smoothly, not pushing the rudders across the boat. Adjustments in steering and trim must be smooth. Downwind the crew weight should be together and slightly forward. If your combined weight is over 290 pounds you should be sitting forward downwind in all conditions. Here the skipper must build up speed and then head the boat down, when the boat starts to slow again, the skipper should head up and gain speed again. This process must be continued the whole downwind leg.
5 - 15 Knots
These are optimum winds for the M-16 scow. The boat performs best with smooth steering and consistent crew work. The angle of heel should be flatter now. The windward rudder should be skimming the water. Once you have two on the high side hiking the rudder should be 3/4 of the way in the water. Crew weight should be together with crew hiking at an angle back towards the skipper. In choppy conditions both should shift back slightly. Downwind the crew weight should be placed together and on the windward side if there is enough wind. This however, will only be effective if you lean out and heel the boat. Weight again should be forward. With the leaning out of the crew the boat will not nose dive. Just lean the boat, steer down and increase your momentum for the next set of waves.
15 Knots and Up
The main thing in this amount of wind is keeping the boat on its lines and not letting it stall out in the waves. If this happens this increases your chance of getting a big puff and having it tip you over. This is because your speed is not up to where it should be for the wind velocity. The crew should have the jib sheet in hand so if this does happen a simple ease of the jib sheet will allow the boat to head up and stay on its lines. The skipper must constantly be working the mainsheet so the boat stays flat. Easing in the puffs and a trim back in with the lulls will give exceptional speed. Your boom vang should be very tight so the mainsail does not get fuller when you ease the sheet. With this process and hiking hard, you can be a very competitive boat regardless of your combined weight.
All these generalizations are norms and averages that have proven fast over many years. Some experimentation by your part may be necessary to fine tune your particular rig and sailing style.
Sailing Upwind in Heavy Air
By Tom Welsch LE-11
Sailing an M-Scow is pretty easy in heavy air. I think it is! Unfortunately, for most “M” sailors, sailing in heavy air is an exercise in hiking and fatigue. The consensus of most sailors is to drop the traveler, tighten the Cunningham, pull the jib car back, and hike, hike, hike. I have been pretty successful in the heavy stuff. Yet, most of my crews have said that I don’t hike. Am I lazy?
Maybe the answer to set up your boat a little bit differently. A stationary mast is not necessary (and it is illegal under EMSD rules). I can think of just a few boats that are ridiculously fast in a blow. Rich Moorhouse has a really fast ‘67 Tanzer. Dave Slavinski’s boat may be just as fast. The feature that both these boats share is an extra jib sheet block set 2-3” outboard of the jib sheet track. Some other boats; Rich Neff’s ’71 One Design, and my ’80 Johnson have an extra jib track set outboard between the board well and the jib-track. This may be a better set up. Some people will say that they make a bigger slot by using their barber haulers upwind. I have tried it, but it was not as effective. The barber hauler tends to close the slot in the upper section of the jib. The main reason you set the jib cars aft in heavy air is that it opens up the upper leach of the jib.
I sail with the jib tracks with the conventional set up until I see whitecaps on the water. This is point where I make the switch. You will immediately notice that there is less healing force and the boat squirts forward. I have been able to sail some heavy air races with the traveler at the centerline. With the traveler near the centerline, I can sail at least 5 degrees higher than my competitors with better speed. The Cunningham does not have to be too tight, but the outhaul should be pulled out to the black band. I flatten the bottom of the bottom of the mainsail with extreme vang tension. I have an 8 to 1 vang. I pull on it so hard that the boom develops a noticeable curve. (You may need to pop rivet your gooseneck track periodically) This also rams the mast forward for maximum mast-bend. The vang has to be loosened for tacking, or the mast will not rotate onto the new tack. After the tack, the crew should quickly pull in the jib sheet and cleat it. This is critical, or the boat might go into irons. The vanghas to be retightened after the tack. As the boat builds speed, the windward telltales on the jib will begin to stall. Then have your crew pull in the jib sheet two clicks on the Hexarachet through the cleat.
The motto for the crew should be: “cleat it and forget it.” If the crew lets out the jib sheet during a puff, the boat will stall and heel over. Not fast. The skipper should be the one easing the mainsheet in the puffs. The mainsail will keep its high-speed shape because of the tight vang. The traveler is only used as a baseline to balance the boat during the lulls. The mainsheet is your clutch to de-power in the puffs. Just ease out 6-12” in the puffs and then bring it back in to keep the boat on her lines. I do not recommend changing your mast rake for heavy air sailing. The boat will not point as well and it will screw up your rig tension. You may want to set the boards at a maximum down position setting, which shows the top 3-4” of the board horn.
The Ronstan 5/8” Jib track and cars are used on most M-Scows. As long as the track is not set in the deck, and there is an end cap on the back of your jib track, you can use the outside jib-track system. This system costs less than $15.00. You just need to buy a 12” length of the 5/8” Ronstan track (part # RF365 at Annapolis Sailing Products) and cut it in half. My father recommends getting two extra track end caps (part # RF366). These will be screwed into the back of the outside track to protect the crew. The existing end cap has to be removable, so the rivet or screw that holds it in needs to be removed. Each 6” length of track will be mounted parallel to the existing track 3-1/4” to the outside (screw hole to screw hole). You want the aft end of the outside track to be even with the aft end of the inside track. Drill the holes through the deck and mount the track using stainless steel through bolt hardware. When you see the whitecaps, just pull the jib car off the inside track and move it onto the outside track. Do this with the unloaded jibsheet car; then after the next tack you can change the new unloaded side.
If your jib tracks are set into the deck, you have to mount two extra turning blocks for the jibsheet. Many of the newer boats have this feature. You will need two more Harken jibsheet turning blocks, eyestraps (part# H137), Harken block springs (part# H071), and 4 stainless steel through-deck screws with nuts. This system will set you back less than $50.00. The heavy air turning blocks will be mounted parallel to the existing track 3-1/4” to the outside (screw hole to screw hole). You want the outside turning block to mimic the furthest aft setting of the inside track. Drill the holes through the deck and mount the track using stainless steel through bolt hardware. It will be pretty close to the leeboard wells. When you see the whitecaps, just pull the jibsheet out of the inside turning block and feed into the outside.
block. Do this with the unloaded jibsheet; then after the next tack you can change the new unloaded side.
You don’t have to make these changes to your boat. I have been using this system since 1985. We developed it sailing in heavy air at Little Egg Harbor. It works. When you first make the change, the difference is pretty dramatic. If you are not competitive in heavy air, you may want to give it a try.
Gain Downwind
By Scott & Joanne Callahan (August, 1993)When racing in a one design sailboat, such as an M-Scow, it's very important to have a competitive boat. Competitive is comprised of four basic elements: the boat, the crew, the conditions, and the competition.
In order to be fast on all points of sail, the boat must be sound and fair. What we mean by this is everything must be placed to make sail adjustment easy. Sound means that the boat will work properly, and stay together in all conditions. Fair means that the bottom of the hull, boards, rudders, rig, and sails are as smooth as they can be.
In order to have consistently good crew work, the skipper and crew need to be in good physical and mental shape. A good way to accomplish this is to practice. It is important to know the conditions before the race, as much in advance as possible. The fourth element is the competition. Know your competition.
In order to be fast on all points of sail, the boat must be sound and fair. What we mean by this is everything must be placed to make sail adjustment easy. Sound means that the boat will work properly, and stay together in all conditions. Fair means that the bottom of the hull, boards, rudders, rig, and sails are as smooth as they can be.
In order to have consistently good crew work, the skipper and crew need to be in good physical and mental shape. A good way to accomplish this is to practice. It is important to know the conditions before the race, as much in advance as possible. The fourth element is the competition. Know your competition.
Downwind sailing starts at the ten minute gun. Once the race committee posts the course to be sailed we sail that course in miniature. For example, if the course is an Olympic (triangle windward, leeward, finish to windward), we sail upwind tack a few times, sail our angle to the first reach mark, and determine whether we can fly the whisker pole. We then jibe, sail the second reach to check if we can fly the pole also. Finally, we sail a mini running leg to determine which jibe we will first set the pole, and which jibe we will spend the most time on. Keep in mind that we don't sail the entire course, we just sail the angles. This does two things: 1) It makes us aware of where the marks are, 2) It shows us how are sails will be set.
Approaching the windward mark, we position ourselves so we will have clear air, if at all strategically possible. If not, we have to look for an opportunity to maneuver into clear air shortly after the mark. When rounding the mark, ease the sails, keeping your speed. As soon as the boat comes off enough to fly the pole, the crew moves to set it. We prefer using a pole with ends that close. With the pole in one hand, grab the jibsheet within four inches of the clew with the other hand. Clip one end of the pole into the clew, push the sail and pole forward, and clip the other end onto the mast ring. Then grab the windward sheet forward of the trimming block with one hand, while with the other grab the jibsheet after the ratchet, pulling harder on the sheet before the block. Once the jib is set, jam it. The crew then lowers windward board 4-6 inches. Simultaneously, the skipper, sitting on the windward side, pulls the leeward board all the way up. This can be accomplished with a continuous board pennant. After the crew has the windward board in position, the outhaul lever is released and the jib cunningham is eased. Just before approaching the leeward mark, the crew should retighten the outhaul lever and jib cunningham. The leeboard must be dropped and the pole taken down, pulling the jibsheet so the jib isn't wrapped around the headstay. The skipper adjusts the cunningham and traveler for the upwind leg.
There are three angles of heel when sailing downwind: heeling to leeward, flat with a touch of leeward heel, and heeling to windward. These three positions are determined by the apparent angle fo the wind to the boat, the wind's velocity, and if you are trying to work up or off the wind. Heeling to leeward is done when reaching with no pole in light to heavy conditions. It's also done when running in light air. Flat with a touch of leeward heel is done on a beam to broad reach in medium light air. The reason is too much leeward heel in these conditions will cause excessive windward helm. Heeling to windward is done broad reach 140 degrees apparent to running winds over 10 miles per hour.
When sailing downwind in changing wind velocity, a basic rule is once in a puff, bear off (heel more to windward). At the end of the puff, start to work up (heel more to leeward). When lifted on a running leg, the wind is heading you on an angle away from the mark. Just jibe towards the wind that takes you closer to the mark.
In conclusion, downwind sailing is where more boat lengths can be gained or lost than any other point of sail. Positioning yourself to take advantage of the wind, precision crew-work, and a fast boat are fundamentals that will help you achieve your goals.
Rigging And Tuning the Johnson “M”
(this guide was given to owners to new Johnson M-Scows in the late ‘70’s)
Congratulations on you purchase of a Johnson Class “M”. As one of the most popular
scow classes, whether for one-design racing or enjoyable pleasure sailing, you have made
a wise sailing investment. This booklet will familiarize you with the basic steps in
rigging the “M”, how to tune it, and recommendations on maintenance and storage of the
boat.
A. Rigging The “M” Boat
1. To step the mast, lay the spar on the deck of the boat, sail tunnel
down. Attach the sidestay turnbuckles to the chain plates on each side
of the deck, using the upper-most hole in the chain plates. Be certain
there are no twists in the sidestays when connecting them to the chain
plates.
2. Have your crew hold the base of the spar on the mast step. The crew
should kneel in front of the mast step facing toward the stern and hold
the base of the spar with both hands pushing downward.
3. While your crew is holding the base of the spar on the mast step, stand
in the back of the cockpit, facing forward, and lift the spar over your
head; walk forward, pushing the spar to the upright position.
4. While you maintain forward pressure on the spar, your crew should
attach the forestay to the forward pin in the forestay plate. At this
point, the spar is now self-supporting; the adjustable forestay wire
coming through the deck can be attached to the wire fork end which is
on the forestay. This will permit tension to be maintained on the spar
and stays while the boat is at rest to prevent them from shaking in the
waves, as well as aid in hoisting the jib halyard.
5. Eye-ball the spar from a side view while tension is maintained by the
adjustable forestay. As a starting point, the sidestays should be
adjusted so the spar will be set in a vertical or slightly forward of
vertical position when under strong forward load; use the same setting
on each calibrated turnbuckle.
6. Attach the boom to the spar by sliding the adjustable gooseneck slide
into the top of the track on the spar.
7. Attach the boom vang pulley system (in drawer) to the triangle
aluminum wedge at the base of the spar and to the forward-most
adjustable slider on the bottom of the boom. Use the schackles on the
vang for attaching it to the spar and boom, with the cam portion of the
vang placed on the boom so that a downward pull of the vang rope will
cleat it.
8. Connect the mainsheet pulleys to the three sliders on the boom
(pulleys are in the drawer); the mainsheet should be threaded
according to the following diagram and the end of the mainsheet
should be tied off to the becket of the traveler pulley.
9. Lower the sideboards until the board arm protrudes above the deck
line by approximately 1” to 1-1/2”. Set the board check lines by tying
off each one to the plastic cleat located on the front inside edge on the
board box. Once set, these check lines will control the depth the boards
will drop. (Note: when trailering the boat, it is a good idea to re-set
the check lines in the “full-up” position as a double cleat on the
sideboards.)
Your new M-Scow is now rigged. When hoisting the sails, keep the following
thoughts in mind:
1. If the battens are wood, insert the thin end of the taper first—this
will give the sail more natural curve.
2. When hoisting the mainsail, be sure the boom-vang and gooseneck
boom slide are in the eased position. When the sail is up, the
halyard ball for the mainsail should be locked in the halyard catch
located on the top front of the spar. The rope portion of the main
halyard can be disconnected, with the shock chord loop being
hooked at the starboard side base of the mast to keep the wire
halyard out of the way while under sail.
3. To hoist the jib, put as much tension as possible on the adjustable
forestay; this will help pull the mast forward against the resistance
of the side stays, and make it easier to lock one of the jib halyard
balls in the halyard catch located at the front of the spar. The rope
portion of the jib halyard can be disconnected and stored in the
drawer.
4. Once the jib is up, the adjustable forestay should be eased. Under
sail, the jib itself should support the mast, with the forestay left to
dangle. This will prevent the jib from bouncing as the boat sails
through waves. With the jib up, if the spar is viewed from the side,
it should be set vertical or slightly forward of vertical. The side
stays should be tight as the boat stands at the dock with the sails
up. If there is a significant variance from this, the jib halyard
should be locked with a different ball setting and either more or
less turnbuckle tension should be applied to the side stays to
maintain a tight rig.
5. Upon returning to the dock, first raise the sideboards to prevent the
boat from sailing while tied up. Before lowering the mainsail, be
sure to loosen the boom-vang and gooseneck boom slide. This will
make it easier to unlock the main halyard ball from the catch;
before lowering the jib, put tension on the adjustable forestay.
This will make it easier to unlock the jib halyard as well as keep
the spar and stays from shaking in the waves once the sails are
down.
B. Mooring the Boat:
Some general tips to keep in mind when mooring the boat are:
1. If the boat is kept in the water, anchor the boat with both sideboards fully
up. This will permit the boat to swing readily into the wind in case of a
sudden wind shift in a storm.
2. The stays should be kept tight to minimize the spar from shaking as the
boat bounces in the waves. This can be done by keeping tension on the
adjustable forestay.
3. Snap the jib sheet shackle onto the forestay and tie off both the halyards to
the jib shackle. This will prevent the halyards from chafing against the
spar while the boat is anchored.
4. If the boat is kept on a lift or trailer, be sure to keep it tied down.
5. If the lifting bridle is to be used, connect the two equal length wires to the
aft hole in each chain plate and the longer length wire to the wire loop
holding the skipper’s hiking strap. Be certain the longer bridle wire passes
under the tiller crossbar. In this way, the tillers can pivot upward if the
bridle exerts pressure on them; also make certain the hook that lifts the
boat is through all three loops in the bridle.
C. Tuning the M-Scow:
Assuming knowledge in regard to proper angle of sail trim with each angle of
sailing in the wind, a key to optimum performance is the shape of the sail in
varying wind velocities. Three adjustments on your “M” will enable you to
control the shape of the sail:
1) downhaul
2) outhaul
3) boom vang
Light Wind (0-8 mph)
In these conditions, the sail should be set up to have a “full” pocket; if the boat is viewed
from the stern, the sail will have a great curve to its shape. This is accomplished by
setting the outhaul control on the boom so there is minimal tension on the foot of the
sail. Likewise, the gooseneck slide on the mast should be raised so that the bottom edge
of the sail is approximately even or above the top of the upper white band on the mast.
The boom vang can be left slack. This will allow the boom to ride up, helping to bag the
sail shape. As a guide, the tension on the bolt rope sewn in the sail should always be
approximately equal for both the foot and luff of the sail.
Medium Wind (8-14 mph)
At this wind velocity, at least one person will be on the windward side of the boat to
balance it. The sail shape should be flatter than it had been in light air in order to
maximize performance. The foot of the sail should be stretched further out on the boom
and the gooseneck should be lowered a notch or two. Tension on both the luff and foot
of the sail should be approximately equal to maintain the natural shape cut into the sail.
The boom vang can be tightened somewhat in order to prevent the boom from raising in a
puff—this will help to maintain a flatter sail shape and keep the entire rig more stable.
Heavy Wind (15 mph and up)
In these conditions, white capes will be forming on the lake; puffs will hit rapidly trying
to heel the boat. The sail shape should now be as flat as possible in order to minimize the
amount of sail area exposed to the wind. To accomplish this, the outhaul should be
stretched out as far as possible; likewise, the luff of the sail should be pulled tight. The
gooseneck would be in the maximum down position (bottom edge of sail is even with the
top of the black band). The boom vang should be as tight as possible. This will help
keep the sail flat and the entire mast/boom/sail rig more stable in the waves and sudden
puffs.
D. Maintenance for the “M”:
Very little maintenance is required on the “M”. However, to ensure that the boat
stays “like new”, we recommend the following:
1. If the boat is moored in the water, once or twice a month, tip the boat
on its side at a dock and scrub off the algae with a hard-bristle brush.
2. The gel coat colors can be maintained with a mild rubbing compound.
3. If any wear appears on the mahogany parts, a light sanding with fine
sandpaper, followed by a coat of spar varnish will return the mahogany
to original. If the boat has teak parts, teak oil should be applied to
preserve their appearance (do not varnish teak).
4. Periodically tighten the set screws on the four boom sliders (which
hold the boom vang and three mainsheet pulleys to the boom).
5. When storing sails, be sure they are folded (or rolled) and dry.
6. On the middle of the backbone of the boat, there is a black rubber
plug. This plug should be removed prior to winter storage, and after
tipping over to check for condensation or water. To re-insert the plug,
push a pointed object (screwdriver) in the plug hole and stretch the
plug into the backbone hole.
E. Storage for the “M”:
It is recommended that the “M” be stored for the winter with the following in
mind:
On the middle of the backbone of the boat, there is a black plug. This plug
should be removed prior to winter storage. Tip the boat over to get the
condensation or water out of the backbone or floatation tank. Reinsert the
plug.
The boat should be stored deck-up with the hull supported by two sawhorses or
4x4 planks; this will allow air to pass under the hull. Don’t store the boat on its
side or upside down.
As a guide, the boat should be supported with saw horses or 4x4’s placed under
the splashboard area and under the back of the cockpit. Using the mast with its
foam supports, or in its trailering cradle, cover the boat with heavy vinyl or
canvas. The raised mast will act as an "A" frame to allow air to circulate
through the covering.
