Beavertail Part One

The Beavertail isn't new. I've built it many times. But I copied the step-by-step instructions over from the Honky Dory Plans. I've been through the instructions several times now, editing the text so it makes sense for this design, but there might still be glitches left in the discussion. If you notice anything that doesn't make sense, please let me know. The photo dimensions are correct.

Stitch and Sew Plywood



These plans include drawings, various tool and material lists, full sized patterns, and written instructions for plywood-fiberglass construction. Plywood-fiberglass construction is quick, easy, and well suited for the beginning boat builder. At approximately 275lbs. for a 15' boat, plywood-fiberglass boats weigh a little less than aluminum or "all-fiberglass boats." Note too that stitch and glue boats are not particularly cheap. You might be able to buy a used ClackaCraft for the material cost. Don't build this boat if cost is you main motivation. Build this boat if you want a better-looking, lighter, stiffer, faster and generally superior boat, and also if you like building things.

Fiberglassing is essential in the construction of the ribless boat since the glass fabric and epoxy resin give the boat structural strength as well as a tough and durable finish. Epoxy resin is used for all the gluing in the boat as well as for fiberglassing. Polyester resin, which is used in the construction of "all-fiberglass" boats, is not suitable for wood- fiberglass construction because polyester resin does not adhere well to wood. There are a number of epoxy resin systems on the market that are suitable for boat building, but these instructions assume the use of Gougeon Brother's WEST SYSTEM epoxy products. Read through the entire text of these instructions before beginning any work.

How long will it take?

I once built five boats in 30 days flat, working with one full-time employee. But I can't build a single boat any faster due to gluing/fiberglass hardening times. A friend of mine--an MSU art teacher--built a boat from my plans that was perfect. It was prettier than any I ever built myself. It took him 6 months, working intermittant evenings and weekends.

Montana Riverboats

Sandy Pittendrigh
118 Erik Bozeman, Mt. 59715

Specifications: Beavertail

centerline length--------------------15'
gunwale length-----------------------16'
bottom width-------------------------48"
height at the oarlocks---------------24"
Plywood Fiberglass-------------Approximately 250-275 lbs.

capacity-----------------------------three persons, 1000 lbs.



The curved line formed by the junction of the side and the bottom of the boat.


A thirty inch piece of hardwood, triangular in its cross-section, that joins the two side panels at the front of the boat.


The wedge-shaped piece of plywood that joins the two side panels at the stern end of the boat.


The temporary form on which the hull of the boat is built. The strongback consists of five trapezoid-shaped stations that conform to the shape of the boat. These trapezoidal stations are made from 1"x6" pine boards or chipboard.


A length of 1"x6" pine board that forms one side of a trapezoidal strongback station. Each trapezoidal strongback station consists of four cords the top cord, the bottom cord, and two matching side cords.


The top edge of the side of the boat.


The distance across the gunwales at the widest part of the boat.


The hardening process of resin and hardener. As resin begins to harden, it is said to "kick."

Part One Tool and Material lists

Woodworking tools

You will need a hand saw, and either a portable power circular saw (skillsaw) or a power saber saw. A table saw is handy, but not absolutely necessary. You will also need a minimum of eight C-clamps for installing wooden gunwales. These c-clamps must have a minimum throat depth of two inches and a minimum opening of three inches. The more C-clamps you have, the better. Most rental shops rent C-clamps. I use up to 30 C-clamps per side, when constructing laminated gunwales. Other necessary tools include a power drill and assorted bits (including a phillips head screw driver bit), an orbital sander, flat wood rasp, paint scraper, bevel square, spirit level, hacksaw, a smooth faced hammer, and a sharp block plane. A sharp block plane is a key tool. Keeping it sharp is essential. Buy a carborundum water stone or a fine India oil stone and hone the blade frequently. A small abrasive wheel in an electric drill can be used to re-grind a plane blade if repeated honing has rounded off the cutting edge of the blade. You will also need several sheets of 50, 80 and 100 grit silicon carbide floor surfacing paper, and a few sheets of 180 grit aluminum oxide paper. Rental shops that rent floor surfacing equipment also sell silicon carbide floor surfacing paper.

Table Saws

If you want to build a boat it helps to have a table saw. The table saw isn't a requirement, but it does make it easier to do good work, especially when making gunwales and seat parts.

For those who don't have a table saw and who don't want to buy one, you can make one, with a piece of chipboard and an old skillsaw:

skill table saw

...bolt the skillsaw to one side of the chipboard. Hold the trigger down semi-permanently with a nylon strap-tie (you turn the saw on and off by plugging it in to a live receptacle). Then plunge the blade through the chipboard, turn the chipboard over, put it on saw horses and then use clamps and a straight edge to make an adjustable guide parallel to the blade.

It takes a little longer (than a real table saw) to set up each new cut, but it does cut with a staight even line--does just what you need for cutting gunwales out of 1x10 stock or for what ever else.

Plywood, Wood and Hardware materials (Plywood-Fiberglass Construction)

NOTE: full-length plywood has become impossible to find. You will
have to buy standard-sized panels and do your own
scarfing jig
which is time consuming but not hard.

If you do find full length plywood, don't buy it unless it has a single
scarf joint approximately in the middle of the sheet, where there is the least
bending pressure.

2 sheets 4'x8'x1/4" AA fir marine plywood or 5mm marine mahogany (please read the Plywood-README page!)
2 sheets 4'x8'x3/8" AA fir marine plywood for the bottom (or 1/2")
I use 3/8...but your choice has a lot to do with the water you float: fast shallow water
with lots of rocks? Then choose 1/2"

4 1"x2"x16' fir oak or ash for gunwales (or shorter lengths scarfed together)
8 1"x6"x16' #2 pine boards for the strongback
2 sheets 3/8" CDX plywood for strongback corner gussets
1 lbs 5/8" drywall screws 1 lbs 1-1/4" drywall screws
50' 1"x4" mahogany, oak, fir, or ash for seat frames and other interior parts

Edensaw Lumber

in Port Townsend Washinton is a good source for marine plywood.

The Harbor Sales Company

in Baltimore Maryland is also a good source for marine plywood. Harbor sales has a wide variety of plywoods in stock, and they will crate and ship small plywood orders anywhere. The address and phone number for the Harbor Sales Co. is
Harbor Sales 1-800-345-1712 1400 Russel St. Baltimore Maryland 21230


Gougeon Brothers Inc. (517)-684-7286 706 Martin St. Bay City, Michigan 48706

WEST SYSTEM Technical Manual
5 gallons #105 resin
1 gallon #205 hardener
1 pair mini pumps
1 gallon #850 WEST SYSTEM solvent
1 bag #403 microfibers
1 bag #406 colodial silica
1 bag #407 micro balloons
1 bag #423 graphite powder
1 roll 6" fiberglass tape
120 linear feet of 50" 6-10 ounce fabric, if you want to use fabric type for everything.

Else you might want to use 3.5oz or 4oz fabric on the sides, and 6-10oz everywhere else.

If so, you'll need 33' of 50" wide 4oz fabric, enough to cover boths sides of 4 x 8 x 1/4 panel once. Then you'll only need about 90' of the heavier stuff.
120 total of 50" wide is enough fabric for seat tops, locker covers, etc, plus one thickness inside and out on the side panels, plus two layers on the inside of the bottom panel and three layers on the outside of the bottom panel.

If you want to figure the fabric as tightly as possible, look at it this way: you'll need two times 16' by 4' wide for side panels, inside and out. That's 32 feet, but you need to add a foot for cutting error. Figure 12' long for bottom panel. 3 layers out and 2 inside is 5(12)=60' You'll still need fabric for covering front and back decks, gussets, seat pocket bottoms, etc. But you can get some of that from waste cutouts at the bottom panel corners. Talk to Larry at Raka if you're looking for sale-price bargains.

And remember, saving money is not the reason to build your own boat. If your primary motivation is saving money, buy a used plastic or aluminum boat.