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All the parts that control the shape of a Common Sense Boat are shown on the plans, with all the dimensions given. This means you simply transfer the measurements to plywood; connect the measurements using a straight edge for straight lines & a bendable batten for curved lines. Cut along the lines then assemble the pieces. Literally, connect the dots boat building.

Step by step, here is how you build a Common Sense Boat:

Lay out the measurements for the parts of the boat from the plans onto the plywood.

Cut out the pieces slightly oversized with a small skill saw or a jigsaw.

Trim the pieces to size and to each other with a small hand plane.

Glue & nail framing lumber around the outside of the plywood pieces that form the bulkheads. The framing lumber is only to provide a nailing & gluing surface to the plywood.

Wrap the side panels around the bulkheads. Glue & nail in place (you can temporarily hold everything together with sheet rock screws to check alignment before gluing & nailing).

Nail & glue on framing lumber along the bottom of sides (same as on bulkheads).

1. Lay plywood over the bottom, glue & nail in place.

2. Turn boat over.

3. Add decks, house, hatches etc.

4. Paint.

5. Go boating.

STITCH & GLUE

Stitch & glue boat building was invented in the early sixties in England as a way to simplify boat building. The goal was to make boat building more accessible to amateurs. The method consists of cutting out the parts that form the shape of a boat, stitching these together with wire then coating the seams with fiberglass.

The original experiments with the new technique resulted in a boat called the Mirror Dinghy. This boat was so successful it is still being built. There was only one problem with stitch & glue at the time. The only material available to make fiberglass joints was polyester resin. (What you think of when you think "fiberglass". Polyester resin is far from ideal for boat building material, but originally polyester was all that was available for stitch & glue boat building. Polyesters problems are, it is not waterproof, it is brittle, does not adhere well to wood surfaces and has a short pot life. The pro side of polyesters are there are readily available, inexpensive, and fairly easy to use if mixed properly.

With the advent of epoxy resins formulated for boat building, stitch & glue boats came into their own. Epoxy solves all of the problems of polyester. It is completely  water proof, has good flex characteristics, is a great gap filling glue & has a reasonable pot life. The cons are it is expensive, it has to be mixed accurately and may not be readily available world wide.

This building technique allows amateurs to quickly and easily build a boat with good results the first time out. With the advent of epoxy it became possible, for an amateur. to actually build a better boat than any that are commercially produced. The reasons are obvious.

Plywood combined with epoxy, is one of the best materials from which to build a boat. It is very strong, stiff, light weight, good looking and completely water proof. And best of all, because of epoxy's gap filling properties, stitch & glue boat building is the most forgiving boat building method there is.

Stitch & glue boats do not need to be built over a frame, and do not need extensive internal bracing. Parts do not need to be fit together perfectly to make a perfect boat. In fact, and I still get in trouble with the old time boat builders for saying this, a joint that is off by 1/4" glued together with epoxy is stronger than a perfectly fitted joint held together with any type of glue or fastening method.

With stitch & glue boat building, you really can build a better boat than you can buy.

TOOLS

Minimum tool chest: Jig saw or hand saw, 3/8 drill,16 ft. (or longer) steel measuring tape, three sided scale rule, carpenters square, bevel square, hammer, backing maul, screw drivers, 1/8 - 1/2 inch drill bit assortment, low angle block plane, pliers, wire cutters, and at least four 3" C clamps.

There are many other tools that are at times nice to have but still are not necessary. In many instances tools can be made on the spot to do a one time job. Tools can be found at garage sales, flea markets, rummage sales, discount stores, etc.

PLYWOOD & LUMBER

Easy to build boats are built of plywood. It is readily available, easy to work and still has one of the highest strength to weight ratios available. If you can afford marine grade plywood, it will give you the best results. But common exterior grade plywood will work if it is fiber glassed over it.

For framing lumber, you need a wood that will hold glue & nails well. Fir works best, but spruce or pine will also work. Select a wood that is dry,& as free of knots as possible. Use standard lumber yard sizes to avoid having to re-saw the lumber. You can use expensive hardwoods for trim, decorations, etc.

STICKY STUFF

These boats are made to be glued together. The fasteners are only to hold them together until the glue dries. Epoxy is best. Epoxy is gap filling (in fact is stronger on a poorly fitted joint than a tight one) and does not need much clamping pressure, only enough to keep the pieces together while the epoxy cures. Use epoxy resin, not polyester, if you use the fiberglass butt strap. Epoxy can also be used to coat the boat, with or without cloth matrix, to ease maintenance and upkeep. The only problem with epoxy is that it is not cheap.

As the ultimate heresy, plastic resin glue (Weld wood, Borden's, etc). It is easy to mix, has a long pot life and has been used in boats for a long time. It is not real good at gap filling and takes some clamping pressure but seems to work.

FASTENERS

Common Sense Boats are nailed together, not screwed, using silicon bronze ring shank nails. They hold as well as screws and are much easier to use. Hold things together temporarily and do trial fits with sheet rock screws.

FIBER GLASSING

If you use fir plywood, it will need to be fiber glassed. If you use a high quality marine plywood, fiber glassing is not necessary. But it should be epoxy saturated, to prevent absorbing moisture. Building a boat in this way, The boat will last a life time. If you choose not to over glass the boat. You must at least fiberglass the outside edges. This is explained in the "How to Build Common Sense Boats Pamphlet".

FINISHING

Finishing from prep to painting, can take a great deal of the building time. The amount of prep work you do, will determine how good the final finish is. There are as many ways to finish a boat as there are boat builders, ranging to fast, quick & cheap, to slow & expensive. The choice is yours. Some builders will use cheap exterior paint. This is not a good idea. You do not need to spend a $100.00 a gallon for expensive marine paints. I personally use a good quality marine or industrial enamel paint and I use Cetol instead of varnish for the finish.

If you need more information, please check the FAQ's page. If the answer to the question you have is not there, please go to the e-mail page and e-mail or use the message forum to send your questions. I will get back to you as quick as I can.

CAT YAWL

There are many good reasons why Common Sense Boats use this unusual rig.

First, the sprit boom has several advantages over a boom on the foot of the sail. The triangle of sail below the boom acts as a vane, making it impossible for the sail to twist when reaching & running.

This self vaning feature not only saves the expense of vaning equipment, it makes sail tending much easier. The geometry of the boom transmits much of the driving force of the sail to the mast. This, in addition to the self vaning effect eases sheeting forces, making sailing easier & more enjoyable. Self vaning minimizes the twist in the sail, eliminating cat boats tendency to be hard mouthed (want to round up) when running.

Second, Cat boats, because they do not have high tension that needed to keep the luff of the jib straight can be designed to be free standing. This eliminates the expense & complexity of standing rigging. A well designed cat boat, with a properly cut main sail, can perform with any sloop. being faster on a reach & running, slightly slower to windward. But cats have some well known nasty habits like: charging around an anchor or mooring float & being next to impossible to keep into the wind when raising sail. these vices are eliminated with the addition of the small yawl sail.

Not only does the yawl sail tame the cat, it has other significant advantages. The little jigger sail makes the boat self steering with the wind anywhere before the beam. Self steering is a very useful feature & not one usually found on small boats. Also, the mizzen sail can be used to force the boat out of irons, should you ever be so unlucky.

But most important is the rigs behavior when reefed. In most small boats the helm gets increasingly out of balance as the main sail is reefed. Not so on a cat yawl. When the main is reefed its center of effort moves forward. At the same time its effective area decreases, while that of the mizzen stays the same. The net effect is that the center of effort does not move when reefing & the general balance of the boat is not adversely affected. Quite simply, the helm stays balanced when you reef down in a blow, the time when you are least able to fight the helm.

Once you have tried a cat yawl you will understand why this rig makes so much sense & might even start to wonder why all boats are not rigged this way.