Day 19 (104hrs): Installing BH4 and Starboard Cockpit Side

Aug 27 Update:

We’ve got some momentum now. It feels good to glue in parts. We spent a good part of Sat. and Sun. working on the boat. Earlier in the week Taylor filleted and taped the aft side of BH5 into place and on Sat we installed the port side of BH4 and got all of the seams between BH1 and BH2 taped.


Below, BH4 is split into 3 pieces in the updated version of the CS-20 Mk3. This allows the center panel to be installed after the ballast tank is glassed like a bathtub which will hopefully eliminate the possibility of any leaks. To the left, the BH is cutout and the space behind it is storage at the end of the port bunk. To the right the panel is solid because it will be the front side of the Cooler box. We’re planning to copy Graham’s Cooler design. The right side panel is normally also cutout but I cut a new one out of scrap. The hole could have been filled in with scrap but i had a big enough piece so i just remade it. Here I am dryfitting the 3 together while gluing in the port side part to keep everything square and lined up. A clamp was needed at the top to pull in the gunwale just slightly. Had about 1/8″ gap between the hull side and frame in the middle of the panel which is normal. We always leave gaps like that alone so as not to “dimple” the hull.



Below: a view from the stern. BH5, BH4, BH3 (with companionway cutout). Note the gap for the CB trunk on the port side and a thin 1/4″ gap on the stbd side of BH4 for the starboard cockpit side.



Below: A view of the keel between BH1 and BH2. All the glassing and taping is done in this area. Next up will be installing the cleats to support the forward locker top and final epoxy coats inside the locker. I’ll also be installing an inspection port in the bottom of the BH1 to gain access to the space underneath the anchor locker well.



On Sunday we installed the pre-coated and sanded starboard cockpit side panel. The tabs and wedges worked excellent to pull the part down tight to the hull. Taylor got straight to work filleting and taping the outside joint.



Below: At the same time, we installed the starboard piece of BH4 and glassed it in. This box completes the sides of what will be our cooler space. Next in here will be blocking in blue insulation foam. The center panel of BH4 was again used to maintain the space and keep the frames square and true. It is not glued in yet and won’t be until after the ballast tank is glassed.



Meanwhile, I’ve got the centerboard trunk (also the port cockpit side) coated and almost ready to install. I still need to drill the CB pivot hole out. I plan to make a 90 jig for the drill and drill it by hand rather than try to line it up on the drill press.


Day 16 (78hrs): Glassing the Chines

Aug. 20 2018:

Back to work! Taylor and I took a hiatus from building last month and left on vacation. We spent a long week on Mount Desert Island camping in the Acadia national park and did all the things up there. Very relaxing and no cell service so even better. Then we flew down to Mexico and spent a week with 3 work friends of Taylors and made use of my Uncle’s condo on Isla Mujeres. If anyone is interested in a great Mexico family vacation I can recommend an excellent condo rental :)


Below is a shot of the CB trunk just before closing it up. Even more pictures are on my album…




Note in the top left i decided to cut off the corner of the trunk just to avoid having a little empty space there. Probably another small change we’ll make to the kit. The trunk and lid is glassed of course and sanded and got a final coat of epoxy before bonding the two halves together.  Below you can see three aluminum rails I used to ensure the trunk was straight and flat. These I salvaged out of our closets in the house when we changed them out to have closet rods. They make handy I-beam type straight edges.


The trunk has been sitting out for a while now unfinished and had warped a bit so it was important to dry fit the setup all together to make sure it would be flat and straight and free of twist during the glue up since once the lid goes down it becomes very rigid. I also added a temporary piece of wood inside the trunk the same thickness as the framing near the bottom edge with plastic tape on either side to keep it from sticking to the trunk. The purpose to maintain the width of the trunk when installed until the bottom gets cut open.




The trunk all glued up….



Meanwhile, Taylor expertly filleted and taped the aft edges of  BH2 in place. The two fwd bulkhead are fully tack welded into place and the fwd bulkhead is fully glassed in on the front side already but BH2 has no glass until now. The space between BH1 and 2 also needs glass which will be one of the next jobs.



Finally, we filleted and taped the chines making sure the transom was in place and we checked the width of the boat at BH5 to ensure the side flare was very close to the finished shape which it was.  Below you can see BH5 is sitting in place while the chines cure. Later that evening I went back to brush on a fill coat of epoxy on the chines but being out of practice I used too much epoxy and when i checked it about an hour later i had many runs of epoxy down the inside of the bottom. Oops. Fortunately not too late to clean up.


I think going forward we will try to use more peel ply for the glass taping where it’s just straight easy runs. The peel ply creates a surface tension to hold the epoxy on top of the glass tape resulting in a smooth surface that does not sanding or epoxy fill coats later.


Day13 (66hrs): Glassing the Keel

July 9th:

Finally got back to working on our boat this weekend. Well, I did anyway while Taylor was out of town for the weekend.

I got the keel filleted and glassed after those tack welds had been curing for a couple months just for good measure :).  The large fillet went down without much trouble. I used about a 4″ wide bondo plastic scraper up forward and an 8″ metal drywall knife aft. I was going for about 1/4″ thick fillet over the keel.  Starting at the bow by the time i got the fillet to the transom the front had stiffened up quite a bit in the heat (i had the garage doors open) and i was able to put down my fiberglass right away. I had some peel ply scraps left over almost enough to do the whole keel. The last 3′ or so I just put construction plastic over it to push out the air bubbles and make it smooth. I put 2x4s down to span the cradles and was able to walk on them while I worked. Have to have some ok balance to do that but I could have put down more. I also got some more bulkheads epoxy coated. A bit at a time. Trying to coat things before installing them to make the coating a smaller easier job later.

The next day I mocked up the bunks so we could sit in the cabin for the first time. I also was looking at how 3 ports would look in the side panel. Since we raised the headroom in the cabin of the Mk3 I felt that we had plenty of headroom even with the bunk cushions so our current plan is to raise the bunks a bit to gain some additional storage space under them. We’ll see how it goes. Next we need to finish our centerboard trunk and get the rest of the bulkheads coated so we can install the rest of the superstructure. According to the logbook we’ve spent about 75 hrs working on the boat so far.











Day 9 (30hrs): Unfolding the hull

March, 30 2018: Last night we unfolded our CS20 Mk3 hull. More photos here.

SInce it was just the two of us I made good use of some very nice 5×10″ beams that run across the ceiling of the garage. Some lines down to the side panels acted the part of extra people to help let the sides down slowly. A line around the stern end kept everything in later.

I was a little concerned that the hull bottom panels would be too brittle to take the bend since they’ve been artificially drying in my air conditioned garage for a few months now. The ply feels very very dry and Graham has had issues folding boats indoors for that reason before. I was prepared to pour some boiling water from a tea pot on the outside bottom panels as soon as I got too scared to continue but it was not necessary. No issues whatsoever, the bends were not too severe at all. In fact I used a spreader to push the sides out and intended to do it little by little but I grabbed the fwd bulkhead to try and I had already spread the hull TOO FAR. So she reached her final shape without issue after all. 




Day 2: Finger Joints

The cradle makes an excellent work surface for beginning to glue up the finger joints of the main hull panels. Our work area is large enough that we can go ahead and get the finger joints glued up and also work on other parts at the same time but there are a lot of smaller sub-assemblies that can be completed before you start working on the hull panels which take up a lot of space.

Day 1: Cradle

Kit cut out and ready to start, first we need a cradle!


Welcome to B&B Yacht Designs

We pride ourselves on offering innovative designs with sophisticated shapes, unparalleled performance, and a focus on design details which make the best of boating available to both professional and amateur builders. Around the world, the B&B logo is a symbol of quality and service in yacht design.

Over many years B&B has developed a diverse offering of efficient and beautiful boats. Our designs are born of necessity with an unwavering focus on function, performance, and ease of construction. Our plans are equally professional and comprehensive and all of our work is backed by our commitment to customer service.

test post amanda donate

B&B Donates Amanda Kit to

We’re pleased to announce a recent partnership with B&B has recently donated a complete Amanda Kit to this great organization to help them in their fundraising and awareness efforts for their new Apprentice Program– teenage sailors refurbishing donated boats. Sea-Legs recently acquired a completed Amanda and has had it on display at the boat shows in Providence, RI and Hartford, CT. This new kit will be sold to raise money for their programs and also spotlight the Amanda as a great boat kit for all levels of boat builder and sailor. Thanks to Richard Lathrop and the Sea-Legs team for giving us the opportunity to help. Check them out on facebook.

Above: Amanda on display at the Sea-Legs booth at the Hartford boat shown in CT.

test post NCUM 2017

B&B Boats take First and Second in the North Carolina Ultra Marathon 2017

Congratulations to Taylor and Alan Stewart (Ginger and SOS) aboard Core Sound 17 “Southbound” and Matt Pinkley and Chris Elwell (PinkDog and ChangBiZi) aboard Core Sound 17 “Half Fast”. Both teams sailed their Core Sound 17 in extremely trying conditions and became the only two finishers this year. For race info check out Watertribe NCC. 
For more pictures and video of the start join the watertribe facebook page. . There is also some discussion on the forum.

“Half Fast” finishing the NCC at Cedar Island. Extreme low water in Clubfoot creek forced them to take Adams Creek to CP1 in Beaufort before completing the circuit back to Cedar Island.

Taylor and Alan finish with mizzen only (no we didn’t break a mast). High winds and low water made this year a very challenging sail.

B&B at the 2016 Oriental Boat Show

B&B had a great showing at the Oriental Boat show this year. We demonstrated the assembly of our Moccasin 14 Canoe and sold raffle tickets for a completed canoe to raise money for the Pamlico Community College scholarship program. Below is a video of the demo and the finished canoe.

More pictures from the event.

How to attach a block to an s-hook

We use small blocks on our downhaul and medium becket blocks on our snotters for many of our Cat Ketch rigged designs. The block pictured is a Ronstan 20mm single block (RF-20101). The small end of the s-hook must be opened up to accept the block and then reclosed. The strap of the block must be squeezed slightly in order to rotate smothly in the closed hook.

What you will need:

-Bench vise or C-clamp and scrap wood (pictured)

-Pair of vice grips or the corner of a bench vise.

-A medium to large size adjustable wrench

Clamp the S hook with the long side down in the vise or between two blocks of scrap wood as show.

Use an adjustable wrench to twist the top of the round part of the S-hook to the side which will open the hook.

Use a pair of vise grips or the corner of a bench vise to squeeze the top strap of the block as shown. This will narrow the straps inner radius. The radius of the strap should be smaller than the radius of the inside of the s-hook for it to rotate smoothly.

The block on the left is unmodified while the strap of the block on the right has been squeezed.

Test fit the block on the s-hook.

The plastic body of the block may rub on the s-hook. If this is the case, squeeze the strap the other way to increase the height of the strap a tiny bit.

Once the block rotates freely on the s-hook, clamp the hook back into the vise. Almost finished.

Use a wrench to twist the s-hook back into a closed position.

All finished. The block should rotate smoothly on the s-hook.

Why a Cat Ketch?

You may have noticed that B&B Yacht Designs has several models that are cat-ketch rigged.


Perhaps you are not familiar with this rig, and think that it looks “old-timey.”

And, perhaps you think that this rig is not as “efficient” as a “modern” sloop rig.

First let us dispel some common myths about the cat ketch rig.

The rig type is, indeed, one that has been around for many years, and one which was greatly favored by the watermen of the East Coast before the age of power. The rig fell out of favor not because it was inefficient, but because working sailboats became obsolete, and the recreational sailboats which have been built since, are influenced not by the need for efficiency and speed, but by an artificial rating rule. Such rules, made to “equalize” boats on a race course, often penalized the very things which made a boat fast. So designers’ of “modern” boats designed boats that could get the greatest benefit from the lowest rating – and not necessarily the best and fastest boat they could have designed. When ratings were not an issue, the cat ketch has been a rig favored for it’s gentle ways. Several designers in recent decades have utilized this rig to great advantage on some contemporary, even avant-garde designs. In head to head competition, cat ketches have performed well. Our boats have an admirable racing record, although they were never designed as racers.

What are the unique advantages of the cat ketch rig and why have we chosen it for some of our designs?

Before going on, let us say: We are not missionaries for this rig. It is not a trademark of our designs in that it in no way represents the rig on the majority of our plans. It is however, a rig, which we have found to be extremely suitable for certain types of boats. So, it fits with our philosophy of making each design work as well as it can for it’s type, while retaining a cost effective approach without compromising quality or performance.

The well-designed cat ketch rig is a simple, inexpensive and balanced rig.

The sail plan spreads the sails along the length of the boat on two masts. The low center of effort afforded by the fore and aft, rather than upward, spread of sail, produces less heeling force.

Free standing masts require no rigging; making them quick to rig and unrig, easy to reef and inexpensive. They also offer an innate degree of safety: the masts bend during gusts, flattening the sail and de-powering the rig.

Each spar is lighter, smaller and easier to handle. This is really important with beach boats, day boats and other dry-sailed craft. It only takes a few minutes to rig. In our designs, up to about 20′, stepping the masts can be accomplished by one person. Being able to get in and out of the water quickly and easily makes sailing so much more accessible. If you have to contemplate an hour of preparation just to go sailing; it isn’t likely that you will go sailing for an hour! In today’s busy world you may have only a few days when you are free to take the whole day for sailing. On the other hand, we all have the odd hour or two of free time, and when the boat can be launched and retrieved in minutes, you can spend that hour sailing. Our larger or cabin boats utilize hinging masts in tabernacles that can also be setup quickly with one person

Docile. That is probably the best word for the behavior of this rig. Your days of yelling, “prepare to tack”, “tacking” – “let it go”, and “pull it in” are over. When you want to tack, you simply put the helm over and off you go on your new course. The sails will tack themselves. This may be a little un-nerving at first. If you have been sailing only sloops or ketches with headsails up until now, you will feel like you ought to be doing something. We’ve noticed however, that it takes the average sailor only about 3 tacks to get used to this laid back approach. By the 5th tack they are enamored and begin to aimlessly tack back and forth with a great big grin on their faces. The crew is equally happy, because they haven’t moved a muscle or been yelled at during the whole procedure. As delirious as the tack may make the laid back crew, they will really get excited by the jibe. Jibing has traditionally been a recipe for disaster, with such fanciful names as the Chinese jibe, invented to describe just one of the multiple possibilities for complications. In the cat ketch rig, jibing requires exactly the same degree of panic as the tack we just discussed…you just put the helm over, pull in some excess sheet if you wish and let her slide out the other side.

Upwind. The cat ketch rig is handy and comfortably close-winded. Provided you have a good hull under you (never blame a good rig for a poor hull design), she will go to weather nicely.

Reaching & Running: Since the sprit bisects the sail load, the area above and below the sprit are balanced. So when the sheets are eased, the sails go out and stay out with none of the collapsing and filling that is the bane of the normal jib behind main. Nor is there the twisting off of the typical mainsail, when the boom lifts and causes a “death roll” in strong winds. Somewhere between a very broad reach and a run, the main sail will begin to shake and lose power. This is not a problem, just turn off the wind a bit further, jibe the main across and return to your desired course.

As you have already learned, jibing, the bane of most downwind sail-handlers is a snap. With a cat ketch rig you can also sail directly down wind, wing and wing. The boat feels stable and whisks along nicely. If the wind gets up and things get hairy, on an unstayed rig (which includes most smaller cat ketches) you can just let those sails go forward of the beam. This will immediately stabilize the boat. Also, the sails when they are allowed to go forward (about 20° ), will keep the boat tracking downwind, so it makes a very easy time of what would be the most delicate conditions for a sloop or cat rigged boat.

Taken to it’s extreme, you can make delicate and gentle downwind landings in any weather by just letting the sheets go and allowing your sails fly forward completely, at the same time lifting your centerboard and letting go of the rudder pennant to lift the rudder…you glide into your (shallow) landing under complete control. This is a far cry from the usual tension and chaos of a downwind landing on a blustery day.

The anatomy of the cat ketch rig:

There are two masts, one set close to the bow which is the mainsail and a mizzen which is usually near or just aft of the center of the boat. The mainsail is larger than the mizzen – although the sails are much more evenly divided size-wise than in a jib-headed ketch. (And to answer the question many ask: yes if the forward sail is smaller it is a cat schooner – not a cat ketch rig).

The sails may be of any shape – some have gaffs; others, like our designs are marconi and have sprits not booms.

We chose sprits rather than booms because they are quick to rig and cheap to build and easy to stow (smaller models use simple and available fir closet rod)…

The sprit is a diagonal spar which holds the sail between the clew and the mast – it serves the same purpose as a boom. We like it in small boats particularly – because it eliminates the boom moving across the cockpit of a small boat and eliminates the need for a boom vang. If you are in the way during the tack, the sail just slides over you harmlessly (the one exception: do not sit directly in front of the mizzen mast on the middle seat, or you could get hit with the main sheets or the clew end of the sprit).

The sprit is attached to the clew with the end poked through a loop of webbing or rope. The forward end fits into a rope which is lashed to the mast (a snotter). This controls the height of the sprit and the relative leech and foot tension. Because these are all “soft” fittings, they are easily adjustable. There is a line to a cleat so that you can adjust sail draft while underway.

Sprits may be either straight or curved. We have done some informal tests and have not found that the curved sprits are enormously superior, although some people prefer them.

We are asked if full wishbone booms are more efficient, and yes, they are – but the little  bit of extra efficiency comes at the expense of simplicity and cost.

If you are a good wood worker and like laminating things, curved sprits and wishbones are a nice touch and they can be made quite pretty.

The sprits are placed on opposite sides of the sails; in other words if the mainsail has the sprit on the starboard, the mizzen will have it on the port. Although the sail flops over the sprit on one tack, it does not affect the efficiency as much as it might appear to.


Shortening sail can be accomplished in two ways. In smaller models, the simplest way is to first, remove the mizzen and place the main in the center (single) sail position (given on all our plans for this rig). If the wind continues to pipe up, change down to the smaller mizzen sail. The second way to reef – which may the most desirable on the larger models, and an option for the smaller models for those who may not be comfortable with the mast exchange, is to have normal reef points in the sail and add halyards.

The combination of the sprit rigged cat ketch and a centerboard board allows for a great deal of adjustment for balancing out the boat in any conditions. If there is some lee helm in light wind, the board can be lowered further, moving the center of lateral resistance (CLR) forward or you can adjust the sails without lowering the board – sheet in the mizzen or let out the main…or combine the three options. Weather helm? Reverse the procedure. Normally (as designed) the helm should be neutral at 8-14 knots, with an increasing weather helm as the wind increases. When the sail/board adjustments are not quite enough to neutralize the helm, you can reef. You will always be able to trim to balance the helm in any conditions, by these methods.

Some Tips for Sailing a Cat Ketch:

  1. Because the sprit bisects the angle of the sail, there is very little load on the sheets. A simple cleat is all you need.
  2. Our designs call for, and we strongly advocate the use of double ended sheets, so that no matter which side of the boat you are sitting on, you can adjust the sheet without leaving your position. (Remember this is laid-back sailing).
  3. In windy or gusty condition, you always have the end of your double ended sheet close at hand and if you get a strong gust and feel you have heeled to an uncomfortable angle, just let the mainsheet go to reduce wind pressure and heeling force. WARNING: Be sure that you release the mainsheet (the forward sail) first. If you let the mizzen go first, it moves the center of effort forward and the boat will bear away which will increase the pressure and heeling and could cause a capsize.
  4. When sailing in light air, if your sails get a vertical crease close to the mast, ease the luff tension.
  5. When the wind is heavier if you see horizontal crease near the mast, increase the luff tension.
  6. Use the snotter line to adjust the relative tension of the foot and leech, they should be evenly and equally curved. So if the leech is tight and the foot is full, lower the angle of the sprit and for a tight foot and loose leech raise the sprit angle.
  7. Grounded! The day will come when you will run her aground in a strong breeze and you’ll get the centerboard stuck so you can’t raise it. The boat will swing around to a somewhat beam-on position. Now in most boats you’d be in a nice pickle…but with the cat ketch, just let the main (foresail) go and the center of effort will go so far aft that she will spin around and tack – then you can re-sheet your forward sail and sail off.