Author: steve_reynolds

I have now drawn these lines 4 times – starting at 1/8 scale, to the dimensions of the boats I saw in western Maine, which were narrower and more shallow than the Dale Tobey boats, and then three times at 1/2 scale.  The lines above have stations spaced 18″ apart which is adequate for constructing a solid form, and the forward station is placed approximately 20″ in from the outside of the stem.  The station at the stern is just inside the transom.  I drew the body plan at full size (above) and lofted the waterlines, buttocks and diagonals at half scale to fair the body.  This method I think was satisfactory but I will know for sure when I assemble the mold stations and check the fairness of the lines.  The lofting is time consuming.  It took me the best part of 3 days to develop the 18″ station plan from the 24″ station plan.  Lofting a 20′ boat at full size requires a space at least 24′ long, plus cost of the plywood for the surface, and I hope the 1/2 scale method was good enough.  See Howard Chapelle’s Boatbuilding for a thorough discussion of lofting.  Here is the table of offsets for this version :

Picking up the shapes of the form molds from the body plan – The body plan is drawn to the outside of the planking and the lines must reduced to get the shape of the plywood stations which make up the form.  The total thickness of the reduction is: 3/16″ planking plus 3/8″ ribs plus 7/8″ form sheathing, or 1 7/16″.  There is also a cutout in the form molds for a backer behind the inner gunwale, which will be 3/4″ x 1 1/8″.  The form sheathing is clear pine strips 7/8″ x 1 1/8″ – I could probably have used 3/4″ but will try the 7/8″ for a more solid form, although it will make fixing some of the strips more difficult to twist into position.I set the dividers at 1 7/16″, hold them at a right angle to the curve of the body plan, and trace a line onto a piece of paper placed over the body plan.  I can see the lines of the body plan through the paper.  I draw in the cutout for the gunwale backer.  I don’t trust the paper to retain is shape for days, so I transfer the new line right away to my mold material – 3/4″ CDX plywood.

The mold shapes transferred to plywood using carbon paper – keep everything square.  Now I can start assembling the form.

This post is a continuation of a previous post describing a project to build a Grand Laker-type canoe.  My intended method is to build a traditional cedar/canvas canoe structure, which means first of all building a form since that is how those boats are built.  I refer you to Jerry Stelmok and Rollin Thurlow’s book The Wood and Canvas Canoe for a complete explanation of building both a form and a canoe.  The prerequisite for any boat is a set of plans and at this stage in my project, the plans are still the focus.  There are no readily available plans for the Grand Laker canoes that I have been able to find; Gil Gilpatrick of Skowhegan Maine has published lines for a Grand Laker-type, but he does not know of any pictures of boats built from these lines, and neither does he use this type of boat.  Consequently, my project at this point is a matter of developing a set of lines that will become my boat.

A comment on building method – I prefer cedar/canvas type construction with the modification of using either an epoxy filler on the canvas, or fiberglass/epoxy instead of canvas.  I want the strength of the epoxy in the covering; as canvas gets wet it gets waterlogged and heavier, as well as prone to rot without the old-time lead-based paints and fillers, and is not as tough as an epoxy-coated skin.  I prefer the appearance of the ribs and planking on the inside of the boat as compared to a strip-built boat, and I also find it enjoyable to assemble a rib/plank boat.  Strip-plank has its merits, but to my eye aesthetics is not one of them.  So much for disclosure.

Making a form takes about as much work as making a canoe, so the importance of making a form in the right shape can’t be overstated.

The previous post came up with a set of offsets for a square-stern canoe of the Grand Laker-type that needed to be validated somehow if it was going to be the basis of my new form.  Further digging revealed a number of characteristics of similar boats that I decided to incorporate into a revised design, as well as illustrating the ways that these boats vary.  First, general dimensions –

I found that my original design of 42″ x 17.5″ was on the narrow/shallow side.  The Old Town square-stern boats were really just guide canoes with the tail-end cut off and replaced with a transom, no doubt how the whole class of boats got started, but most of them evolved quickly to deeper and wider.  Of the boats now being built, only the Grumman approaches the Old Town, which is not to say the Grumman is not widely accepted, which it is, but I think it can get away with the shallow depth by being very flat through the bottom.  My first design, modeled on the boats I saw in western Maine, came fairly close to an accurate copy, but I also now see that those boats are suited to the small lakes they work on and may be uncomfortable on large water.  Further, I started to see that most the the Grand Laker / square stern canoes had a lesser-or-greater amount of tuck in the stern that I had not put in my first design – this is the Scott freighter model –Below is Jerry Stelmok’s Moosehead Laker –

The description of the Old Town square-stern canoes at the heading of this blog mentions the cutaway stern, and the boats in this picture taken at Grand Lake Stream all show a marked tuck –I was able to study a boat built by one of the two remaining active builders in Grand Lake Stream, Dale Tobey, and he uses a more gradual cutaway than the boats in the picture above, but still ends up with about 3″ of tuck over the stern 4′ of the boat – bad picture, but usable – for one thing, how else are you going to go from a center depth of 18+” to a 15+” transom for a short-shaft outboard?The boat above is a Dale Tobey built for John Arcaro of Grand Lake Stream.

Another question for the designer is what form to give the hull in terms of bottom arch and rocker.  Of the dozen or so boats I have looked at, mostly in Grand Lake Stream, the bottoms are all shallow to moderately arched, with little to no rocker until the stern tuck.  This view of the inside of the same Toby boat as above shows quite rounded sections – As does this boat on the shore of Pocumcus Lake, although appearing flatter in the center.I also saw boats at GLS that were similar to the western Maine boats, known in GLS as ‘pickerel’ boats for the narrow form, such as this one that Mike Remillard showed me – The wider boats make more sense to me, and my next step is to re-draw the design to aim for a boat 18 1/2″ deep inside, 44″ wide to the outside, straight/no rocker keel until the start of a 3″ tuck about 4′ in from the stern, with a shallow arch through the body plan. Until next time…

I got my first up-close look at these canoes in western Maine this summer, and have started a project to build one for myself.  In this blog I intend to document the process for those who are interested.

When we went, we weren’t sure we would even be able to canoe on the ponds for an afternoon since they are entirely privately owned, as is the access road.  We went there on a hunch we could get in, having a day free after a canoe trip on Flagstaff Lake.  Least of all did I expect to be measuring boats – so it was a very pleasant surprise not to be turned away at the gate but instead allowed in for a nominal fee, and the guides with canoes we met were not unwilling to talk about the boats.  I used a stick to take rough measures of one of the boats, and got two pieces of information from one of the guides – the transoms are now about 24″ wide, and the maximum girth was somewhere around 5 1/2′ gunwale-to-gunwale.  When we got home I transferred my stick measurements to feet and inches and came up with a boat 20′ long, 42″ wide to the outside of the planking, 16 1/2″ deep inside, with a transom 16″ tall by 22″ wide and a stem about 27″ tall from the outside of the bottom.  These dimensions were the beginning of my collection of dimensions from which I am now working up a set of offsets.

One of the guides told us that the boats were mostly built locally, developed from one boat brought down from Grand Lake Stream, and that his father built most of the boats, and still had the mold.    The boats we saw were traditional cedar/canvas construction, except now fiberglass-covered, as I assumed they would have to be given their heavy use.  The youngest boat in the camp was 15 years old.  Motors were typically 5 HP 4-stroke, but 2-strokes were still in use up to 15 HP.

I worked up a set of offsets from the dimensions I had, drawn at 1/8 scale.  Briefly, the offsets represent sections taken perpendicular to the length of the boat that are cross-sections of the hull along its length.  They become the shape of the mold on which the boat is built.  The drawings which are used to develop the offsets are views of the boat from three directions : End-on, from the side, and from above.  These are called, respectively, the body plan, profile, and half-breadths.

Looking at these boats, the maximum beam appeared to be somewhat aft of center, and carried aft more than forwards, to a quick taper at the stern.  This made sense given that the motor might weigh up to 80 pounds, plus gas tank, plus guide sitting at the very stern of the boat (not to mention the 12-pack).

I had enough information to lay out the profile view and the sheer line of the half-breadth view.  I marked 10 stations, with #1 and #10 at 1′ in from the bow and stern, and the others 2′ apart for a total length of 20′.  I assumed a very slight rocker to the keel, and a rake of 2″ on the transom.  I could now start the body plan, taking the sheer heights for each station from the profile view, and the widths from the half-breadth view.  For this stage, I also assumed a pretty flat bottom with gentle curves through the turn of the bilge, a little flare in the forward sections and a little tumble-home in the aft sections.  After drawing up sections that seemed reasonable, I took the measurements of each station off the 1/8 drawing and expanded them and redrew everything on a 11′ x 20″ piece of plywood to get a half-size drawing.

Howard Chapelle’s book Boatbuilding has an extensive explanation of the process of lofting; the purpose of lofting the boat, which means drawing out the shape in full size or some easily-scaled fraction of full-size, is to assure that the shapes of the sections, when assembled on a form, will produce fair curves without bumps or dimples.  (this is a major over-simplification)  It is easy to picture 3 sections which, when viewed end-on as in the body plan in the middle of the drawing above, appear to be smooth transitions one-to-the-next – but, when actually placed in their respective locations on the building form, do not produce smooth curves at all.  Lofting is intended to identify this error and provide a method for fixing it.  If you purchase a set of offsets that has already been lofted and corrected by the designer, you don’t need to go through the lofting process; you just have to draw out the sections.

In my plan above, the vertical lines on the body plan are called buttocks and represent vertical slices through the hull running the length of the boat.  The horizontal lines in the profile view are called waterlines and are horizontal planes running through the hull parallel to the keel.  The reference points which define the shape of the stations in the table of offsets are : Half-breadths (widths) to the station at each waterline, and heights to the station at each buttock.   The ‘diagonal’ is a diagonal line through the sections at an arbitrary location.  The table of offsets for the design above is :Lofting takes each point along a given reference plane and plots them on the drawing to see if they can be connected with a fair curve.  For example, waterline 18 goes from 2.75 inches at Station 1 to 11.938 inches at the transom.  Drawing this line out will show which stations are out of fairness, and need to be corrected.  Lofting this plan meant drawing out all the waterlines, and the sheer, as well as all the buttocks.  The offsets above have been corrected for fairness.

Unfortunately, I next discovered I had drawn a boat that was not representative of a typical Grand Laker, and I had to start again.  To be continued.

After assembling the body the ledges for the binding are cut and the binding glued and scraped smooth.  I chose to use black walnut for the contrast with the white maple.  There are two pieces to the binding all the way around, a taller piece with some black-white purfling on the bottom and a small square piece that sits inside the outer piece and adds visual depth.  The walnut is first bent to shape on the bending iron – the pieces are about 3/32″ thick and I have to bend slowly to prevent breaks.  The binding ledge is a two-step affair, cut with two passes on a router setup in a router table with a special cutter guide that sets the depth and height of cut.  Gluing the binding is a messy process – everything is held in place with masking tape until the glue dries – but careful work starting with a small block plane and going to a cabinet scraper yields satisfyingly clean results – After the binding is done, about six hours of sanding results in the body being ready for the first finish coat – a sealer of thin shellac which protects it from stains and minor dings during the remaining processes.  Then, the neck dovetail is cut using a router and jig and 1/2″ dovetail bit.  Below, it has been coated with red chalk to facilitate fitting the neck dovetail.

I had a few pieces of 3×3″ quarter-sawn stock I kept from the tree this guitar body came from (it’s a graveyard guitar, remember?) and I chose one of these to make the 1-piece neck.  Below is the neck ready for gluing the fingerboard on – peghead ears and veneer (curly maple) glued on, peghead tapered to final thickness, truss rod slot cut, truss rod and truss rod cover installed, dovetail cut and fingerboard extension glued on.  Next step is to glue the fingerboard on, radius it and finish sand it, put in the frets, level and dress the frets, carve the neck to its final shape, sand and put on a shellac sealer coat, fit the dovetail and glue the neck on.

Finished, minus the finger rest and pickup –

Starting with the glued-up top and back wedges, the outside contours are established with a gouge and hand planes using templates as a guide.  I use Bob Benedetto’s book on archtop guitar making as my main reference, and the templates I use are from his book.  There are templates for the lateral curves too – once the basic shape is established it is a matter of smoothing the contours to blend together, ending up with a cabinet scraper.  These are the tools I use to carve the plates – a Swiss gouge, and two small wood bodied hand planes made from drawings in Irving Sloane’s book on guitar making.  The hand planes have blades of Japanese steel that came from Woodcraft.  One plane is arched both ways, the other is only arched in the long dimension.  The two halves of the plane bodies are glued and riveted with copper rivets.  When the outsides of the plates present pleasing curves – they are used to establish the rough shape of the inside by taking them to the drill press which has been set up with a 1/2″ bit that stops 1/4″ above the table – this leaves a series of holes that gauge the rough-out depth of the inside.  It is a matter of work to bring the inside down to the level of the gauge-holes – From there, the plates are thinned to their approximate final thickness using the planes and a thickness caliper – the back is taken to a uniform 3/16″ and the top varies from just shy of 1/4″ down the center to 1/8″ around the edges.  I did not use binding on the f-holes and felt that this particular piece of spruce needed some reinforcement that would normally have been provided by the f-hole binding.  So – a very thin red cedar veneer was added on the inside, with the grain of the veneer running across the grain of the top.  I chose to use an X-brace on this top to help distribute the vibrations to the outside of the plate, and gave the whole inside of the body a light coat of shellac to help retard moisture transfer in-and-out.  The back was glued to the sides before gluing on the top.  The top – ready to assemble – and, in the gluing form with the spool clamps tightened up – more to come.