Montana Riverboats Test Domain Roadkill



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Making a work table

If you are working over a wooden shop floor it is possible to skip the work table step and to build your side and bottom panels directly on the floor of the shop, over visqueen.  That requires a bit too much bending over for old guys like me but it is possible.  Most builders will be working over a slab floor.

If so before you do anything you need to make a large work table by placing 4 extra-straight 16' 2x4s over saw horses. Then you screw (drywall screws) particle board to the 2x4s. Now you've got a table to work on. My shop has a wooden floor so I sometimes skip the work table step and simply put visqueen flat on the floor.  And work over that.  My back always complains before I'm done however.

First you scarf two 4x8 (probably 1/4" inch) plywood panels together to make a single 4x16' panel (that's an approx length, detailed instructions come later). And then you cut the 4x16' panel diagonally down the middle to make the two side panels. Then you scarf two more sheets to make a bottom panel.

Then you put visqueen over the work table and fiberglass the panels. Only pre-fiberglass the inside surface of these panels. I typically use 3.5oz or 4oz fabric for the side panels and 10oz fabric for the bottom panel. But fiberglass is versitile stuff.  More layers of light fabric is roughly equivalent to fewer layers of heavier fabric. Then you layout the side panels with pencil marks at the right places (where they fasten temporary rib-like trapezoid-shaped formers).  .

Then you cut out or make a few trapezoid shapes (from chip board or 1x6" boards). These trapezoids are essentially temporary boat ribs. Then you screw the side panels to the temporary ribs. Then you pull the front of the side panels together and screw them to the stem. Then you add the transom at the rear (still no bottom panel) and voila: it starts to look a lot like an (upside down) boat.

Then you straighten up the boat (before adding the bottom panel). Then you add the bottom panel, fiberglass the outside, flip the boat over, fiberglass the inside, add gunwales, add seats, paint the boat and then go fishing. The instructions that follow have detailed discussions for each of the above steps. But it's important to get a big picture idea of the overall process before diving into it.

Here is 4x16' foot table suitable for panel assembly, made with hand selected 2x4s, 3/4" inch particle board and sawhorses.

On top of a table like this you can spread visqueen just prior to glue-up steps. If you have a flat wooden floor in the shop you can work there. But if you are working over a slab it's a good idea to make something like this.


Here is a large plywood panel on to of visqueen, on top of that table, during scarfing, where two or more smaller panels are glued end-to-end to make one large one.


Two finished side panels and a bottom panel. Ther side panels are plywood. The bottom panel here is 3/4" inch Plascore. These were cut for a boat larger than the Honky Dory.  But panels are panels at this stage.


Now pre-glassed on one side only.


Attach side panels to forming stations. AKA temporary ribs.  Fasten at the stem.  If one panel side is pre-glassed I usually put it to the inside.


Here pre-glassed one side only panels were put on the outside.  This photo, however, is a Beavertail, which has less bend at the first forming station.  I still recommend puting the pre-glassed face to the inside.


Add Transom.


This hull assembly has a transom twist that needs to be fixed before moving on. They all do.  You just have to fix it first. Notice the centerlines drawn onto the tempory rib formers. Those centerlines were made when the formers were made. They extend from top to bottom.


A masonite siding board can be attached underneath, screwed flush to the centerlines.  In most cases this is enough to straigthen things up. In some cases--for a worse than usual transom twist--a wire can be connected between the stem and one corner of the transom (in addition to the masonite) to straighten it out.  The hull assemble MUST be straight before laying the bottom panel down on top of the upside down boat, and tracing out the edges of the bottom.  Cut the bottom to the line at a slight angle on the skill saw. 


After straightening snap a line down the length of the middle of a 4x16' foot bottom panel.  Lay it down onto top of the straightened hull assembly so the centerline on the panel lines up with the centerlines on the rib formers.  Weight the ends of the panel down with boxes of nails or paint cans.  Trace a pencil line around the perimeter of the chine.  Cut the bottom panel with an angle on the skill saw. Transfer the side angle from the boat to the skill saw with a bevel square.

Now glue on the bottom panel, either by stitching or in this case by simply weighting it down onto edges of wet resin putty.


Apply gunwales.


Ready for interior seat work


Make some seat parts, here I am using 1/4" inch plywood glassed on both sides. These locker pieces do not attach to a frame of any sort. They are glued as is directly to the sides of the boat, as per more detailed instructions in Part1 through Part4.  


Here a temporary plywood box made from plywood scraps helps position and center the side loacker parts, which are simply glued in place.  Side lockers are not required. Many builders use simple seat rails mounted on gussets. The interior is up to you. I supply the most bare bones simple seat rail solution. Many builders elaborate at will.


Make some locker lids.  This boat was relatively flat-bottomed, with an extra-wide transom so I could also use it for zooming around lakes with my 20hp outboard. It works for rivers and for lakes. But neither particularly well, for what it's worth.


Make things as simple as you want.


 or as complex and fancy as you like it.