Montana Pram  

Design by Paul Butler - Port Angeles, Washington - USA
http://www.butlerprojects.com/

This little nine foot pram was among our first project boats published after we moved from the coast to Montana. We had been doing regular boat projects for Outdoor Life magazine and my editors labeled it because they liked the Montana connection. The pram published in Outdoor Life in 1991 and has continued to sell year after year. Its been built in school shop classes, garages, living rooms, carports and back yards--by amateurs and first-timers, single mothers and families. Hundreds have been built and its still one of our most popular boats.

The long line of prototypes of this boat had lived mostly on the foredeck and cabin top of our sailboats when not tethered alongside in the water or dockside. When at anchor the prams served as shore dinghy, supply vehicle, taxi, work platform and extra storage space. The prams also had to be lightweight enough to lift on deck, where they became our hard shell lifeboat. Some versions were car-topped to lakes and streams all over the northwest, up into BC and Alaska.

click to enlarge

click to enlarge

The tough utilitarian design worked well enough for fishing and recreational use, as a car-topper dinghy and even for beach landings in most weather. The sides are a bit higher than I prefer for looks but the extra freeboard came in handy more than once, and of course the sheer line can always be cut down to suit esthetics. If you ever tried to get a big excited dog out of a dinghy and onto the deck of a pitching sailboat, then back off the deck and into the dinghy again, you’ll understand the need for capacity and stability, and this pram is really just the no-frills mid-section of a dory, with the transom and pointed bow cut off. We used oars from six to eight feet long that stowed inside the hull. The shorter oars, tethered to the oarlocks, always seem to work better in rougher water and beach landings and launchings, and the longer oars are better for open water rowing.

FORWARD…… OR AFT??? This pram was an extension of our “simple” boat designs for amateur builders, and is another of my symmetrical hull designs: the hull is the same on both ends from mid-section outboard. With small hulls like this pram, and also with some slightly larger rowing boats I’ve not been able to tell much difference in performance. All factors considered it’s a real advantage and makes the boat so much easier to pattern and assemble. Seating can still be arranged to suit loading and the frames and transoms are identical, inwale and outwale are consistent front to back and fore and aft is pretty much a personal decision depending on which way you want to go. Attaching multiple oarlock sets to the gunnel will allow a variety of rowing and seating arrangements.

CONSTRUCTION The pram assembles quickly and without complicated procedures, and makes an ideal first woodworking project. The transoms and a temporary center section are used as a building base to provide support and a convenient building form during construction. Ply panels are joined using simple epoxy glued butt-blocks, so no exacting scarfing or woodwork is required, and the entire boat can be built of standard eight foot panels. The large interior butt-blocks, structural seats and stringers compensate for the lack of traditional ribs and keep the interior simple and clean. Inwale, outwale, and trim wood can be softwood from your local lumberyard or hardwoods like mahogany.

An extra seat or adjustable seats can be installed as required and made removable along with extra oarlock positions to allow proper trim for one, two, or three people. The pram can also be equipped with fold-down swivel backrest types or folding canoe seats. Build the seats removable and two or more prams will also "nest" together for storage or transport.

click to enlarge

click to enlarge

To minimize damage to the pram and any other boat we laid against we experimented with a variety of cushions and bumpers until we settled on lengths of used and softened firehose which we split lengthwise and attached to the hull with stainless screws and screwcaps. If the anchorage isn’t too rough, you can tie the pram up tight against the hull—otherwise it’ll keep you awake all night banging on the hull. (see “hull cushioning” article in builder resources) But this is really a concern only if you’re using the boat as a dinghy, otherwise a couple of small bumpers will usually do the job for dock ties.

MOTORS My standard reply to builders inquiries about motors was that if the builder wanted to go really fast on the water they should look at other designs. In my experience, when it comes to motors if a builder thinks a little is good, a lot more is better, and I didn’t want to encourage big motors on this small lightweight boat. We did finally add a note about electric trolling motors, but that didn’t prevent many builders over the years from installing small gas motors. The boat apparently performs well enough with a small motor but I still tell builders to use common sense when it comes to motors. It’s a small lightweight boat.

If I were planning to transom mount a small gas motor I’d beef up that end with a half inch or three-quarter inch thick plywood transom plus a timber molding across the top, and I’d also glass tape the perimeter of the transom and install a large epoxy fillet or a big cleat inside. Knees fitted on centerline and port and starboard would absorb some of the added vibration of a gas motor. I’d also add an almost full-length shallow keel for directional stability and hull protection and arrange comfortable seating for the operator so the motor could be operated with safety. One builder installed shallow twin keels located out near the chine of the hull on his motor version, which seemed a good idea to keep it going straight and keep the hull from banging the bottom too hard.

MODIFICATIONS Hundreds of different versions of the pram have been built, from basic bulletproof to ultra-lights, and its been fun reading letters and emails from builders. They’ve been equipped as camp-cruisers to float small streams and even for moderate whitewater, partially decked over and painted with camo for duck hunting, as complex hi-tech fishing platforms or rigged as simple backyard pond drifters for the grandkids. One avid fly-fisherman installed knee braces and a single swivel seat with backrest, and uses a number of 20 pound sandbags for extra stability when fishing. And small beanbags make undeniably the most comfortable seating for passengers while keeping weight low in the boat.

click to enlarge

click to enlarge

We know of one builder who equipped the pram with a single wheel and two wheelbarrow handles so he could roll the boat the quarter mile down to the lakeshore near his cabin. Another was equipped with drain plugs and used as a bath tub on the deck of a commercial tug, where it could be filled from a hose with hot circulated engine water. Yet another version of the pram had two midship bulkheads installed and was hinged to fold perfectly in half--like a clamshell—a somewhat serendipitious benefit of the hull design. (see “2-part boat” article in builder resources) When underway the hull was used to securely stow fenders and dock lines, folded shut and strapped securely down on chocks on the foredeck of a small power cruiser.

One clever adaptation of the pram on a cruising sailboat involved inverting the pram on the foredeck atop the forepeak hatch, and scribing the sheer and transoms of the pram to fit the camber of the sailboat deck. The completed pram hull was elevated 2 inches off the deck on chocks and strapped securely in place atop the open forepeak hatch, which allowed vital ventilation to the forepeak below along with some light and with excellent weather protection. The slight reverse curve in the sheer and transoms must have looked a bit odd when right side up, but worked well either way.

SECOND THOUGHTS With a few years to think about everything plus feedback from all the builders, theres bound to be some second thoughts. Mostly I would emphasize the use of quality hardwood ply and epoxy throughout. We used mostly traditional wood boat-building techniques for the prototypes, as this design was almost pre-epoxy and we didn’t yet understand how much we could improve the boat by using some of the advantages and “tricks” which epoxy made possible. Lightweight ply/epoxy versions of the boat can be made to weigh less than 50 pounds, which makes it an easy car-topper that can be launched and retrieved by one person.

For very light hulls I would go with a 6 mil bottom and 4 mil topsides, all using quality BS 6566 or BS1088 grade hardwood ply, sealed on both sides with a minimum of three coatings of epoxy. I’d use okoume ply for ultra-lightweight and mahogany for looks and varnish over the epoxy for final finish. The minimal layup would involve 2” wide glass tape over exterior seams and an epoxy fillet on the interior. I would also install compartments fore and aft for seating, storage and flotation. All vertical bulkheads would be 4 mil and decks would be 6 mil. I’d also graphite the bottom and strike a waterline about three or four inches up on the hull. The graphite and epoxy mix applied to the bottoms of these small lightweight boats has been one of the most successful features, and allows dragging the boat over launch ramps, gravel and beaches. At the end of the season we use scrapers to clean the bottom and apply additional coatings of the graphite mix.

So while many prams are still built using traditional boatbuilding methods and various grades of even construction grade ply, the ply/epoxy technique produces a near state-of-the-art hull and eliminates all those little stringers and cleats and fastenings. Aside from the screws holding oarlocks there are also no metal fastenings in most epoxy prams. Build it with quality materials, maintain it with common sense, and you can give this boat to your grandkids in about as good shape as when it was new.

click to enlarge

 

PLANS Building plans include blueprints and a 30 page illustrated step-by-step construction manual. The plans encourage modification to suit specific needs. Details include finishing and fitting out ideas, builders tips, material sources and lots of options for customizing. A minimum number of tools are required and the pram can be built with a jigsaw, block plane, scraper and a few clamps, but the usual complement of tools will come in handy.

Plans for this and many other boats available at:
http://www.butlerprojects.com/

________________________

Paul Butler has designed and built small wood boats professionally for over 25 years. He was a contributing editor to the late Small Boat Journal, and with Marya Butler has published 3 books and over 200 magazine articles. Detailed building plans for their most popular small boat designs and other projects can be purchased from the website at: butlerprojects.com Illustrations are by Marya Butler and she can be contacted at: fins_n_feathers@hotmail.com for custom illustration quotes.

More articles by Paul Butler:

SAILS

EPOXY

GEAR