The Lost Coast Chapter of thePage 1: Building frame and station set-up through planking |
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The goals of this project are to construct a traditional rowing boat that is pleasing to the eye and performance oriented. Candidates considered included various peapods, Adarondak guide boats, whitehalls and other wherries. Various plans were studied; advise was sought. Second runner-up is the beautiful and quite similar Wrangley Lakes Boat, but the St. Lawrence Skiff won out. Good words for this craft came from several experienced open water rowers. These boats are known to have been raced. Extended expeditions, such as the Inland Passage from Vancover to Juneau have been successfully accomplished.
John Gardner, in his chapter on the St. Lawrence Skiff in Building Classic Small Craft, says that these boats (like the Adarondak Guide Boat) were designed for a guide to take the well-healed Eastern City Dweller of the 1880s out into what was then the "wilderness" of the Northeast for a week or two of hunting and fishing. The boat needed performance, since the guide would be rowing alone and wanted to get his client out farther and faster than his competitors. It needed carrying capacity so that a week's provisions would keep the client comfortable while "roughing it" slightly.
Plans were obtained from the archives of the Mystic Seaport. There are several sets of plans for this craft, but the 20' variation (called Bobby) was chosen because it was the one with the longest water line. "A fair entry" is what is needed for good performance, and this entry is as fair as the lapstrake design will make it.
A big challenge is having the space to construct this boat. The boat is of lapstrake design with seven strakes on each side. It is constructed upside-down on a rigid frame over station moulds. The reader is referred to the many excellent books on traditional wooden boat construction listed in the bibliography. In fact, it is recommended that anyone who wishes to attempt building this boat should either be highly experienced or to read the books referenced.
May 15, 2008
For this project, Jim decided to use a laser level, instead of a string, to define the base line. Everything lines up on the baseline, and the offsets in the plans indicate where each station mould is positioned in reference to this baseline. It was thought that setting up a laser level on an adjustable stand could make measuring accuracy better, and would not get in the way like a string does.
It turns out that the laser level was of limited utility, due to the difficulty of lining it up properly. It was very sensitive to the wind, and had to be realigned frequently.
The trade-off was improved accuracy and ease of measuring and marking.
A rigid frame is constructed from 2 X 6" lumber. Since the boat is 20' long, a rectangular frame with short legs was constructed that is over 20' long and is 30" wide. It was chosen to use five station moulds, but offsets for nine are in the plans; the obvious choices are numbers 1, 3, 5, 7, and 9. Station moulds, stem- and stern-posts were lofted and cut out well ahead of time. The distances between the station moulds were carefully measured and marked, then the moulds were attached to the frame. One has to be willing to attach, then remove and realign in order to get everything set up straight and square, with the moulds centered and the proper distance below the baseline. Once the station moulds are securely in place, the stem and stern are attached.
May 21, 2008
The keel, or bottom of the boat is laid on and should fit easily into the notches that have been carefully cut into the station moulds. These had previously been measured with as much precision as possible, then cut. In this case, a local piece of Douglas fir was available that was fairly clear, locally cut and milled, then air dried for a few years. The piece was cleaned up, cut and planed to the correct demensions, then shaped - again from measurements available on the plans. The bottom is glued to the stem and stern posts with epoxy. The joint will be strenghthened by the first plank - the garboard, so the joint does not need any extra fastening. Battons are now placed at the marks on the station moulds that determine the edges of the planks. One wants smooth, "fair" lines with the proper spacing, so defining them with battons helps visualize the shape of the plank. If you have laid out and cut the station moulds accurately, fair lines should correlate with the marks on the station moulds.
One more last careful set of adjustments in the set-up now occurs. This is where the laser level comes in handy. Using the marking guage and ruler, a center line is drawn on the bottom, the heights of the station moulds and bottom are adjusted, and everything squared up and secured in place. The measurements can be done with a fair amount of precision using this technique.
May 27, 2008
The bottom is now beveled. The angle of the bevel goes from just a few degrees in the center of the boat, and becomes quite acute at the stem and stern. This is what gives the boat such a clean entry and no turbulence aft. Using the batten at the end of the first plank, the plane of the garbord is established. Using a straightedge, the intersection of the plane of the garboard with the bottom plank can be marked. A power planer is then used to plane this complex curve. A lot of material is removed, but one does not want to remove too much. When the bevel starts coming close to the correct angle, the use of the straightedge can be helpful to define the bevel accurately.
June 4, 2008
Now it is time to start shaping the garboard strake. The rough shape was determined by marking out a spiling batten. It was found that a 6 3/4" plank will make the nearly straight garboard. It will be made just short of 20' long by scarfing two 8' and a 4' plank. Scarfs are made by pin nailing and clamping a stack of short planks. A 2 1/2" scarf joint is then set up by stacking the planks and pulling each one back exactly 2 1/2". The power planer is used again, this time planing a nice, clean taper into the stack of planks. Plywood is easy to get a good scarf, because of the way the layers stand out Getting a clean taper means keeping all the lines exactly the same width.
The planks are then aligned and glued with epoxy, creating two 20' planks. Care in lining up the grain pattern must be included. The planks are then measured and cut according to your favorite method. Excellent descriptions are present in many of the references. Besides being as accurate with the measurements as you can, it is also critical to keep the lines "fair", meaning having a smooth and natural-looking curve. Or straight line, as will be needed for the garboard strake. The lands are at the fore and aft ends of the strakes, where they gradually blend into each other to end smoothly at stem and stern. Excellent instructions on how to cut the lands are present in the references and there are several ways to do them, but here we will be cutting them with a rabbet plane.
June 12, 2008
Shaping the 20' planks and getting them glued into place is a challenge. At this point, it would be good to have several helpers. Slow epoxy is used to give the workers plenty of time to line up the planks perfectly. The garboard is screwed to the bottom as shown on the right, while the plank is held in place at each of the stations as shown on the left.
After the epoxy has dried, the screws and the clamps are removed. Some planing can be done with the plank to adjust the fairness of the first line, but it didn't seem to be necessary here.
June 22, 2008
The bottom is planed flat, then the outer edge of the garboard is planed to recieve the next strake. A good way to do this accurately is to clamp a batten along the outer edge of the next strake and using a simple device like that shown on the left, the proper angle can be planed so that the next strake will land flat.
Following the dimensions on the plans, A bottom plate is shaped. The origional plans called for putting a rabbet into the bottom board, into which the garboard - perfectly shaped - fit. This feat is out of reach of this builder, so in this case, a 3/8" "bottom plate" is shaped and glued on, giving the craft the appearance and functionality of the origional design. Some local chincopen was available; it was planed to 3/8", rough cut with a skill saw, then planed to shape.
June 28, 2008
The bend at the ends of the bottom require saw kerfs to be made. Kerfs were cut an inch apart and half the thickness of the board. After another good sanding, the bottom was slathered with epoxy with same to the bottom plate, and the plate was tacked to the bottom with some pin nails and a screw at each end. The curved ends were clamped to the stem. Drips were cleaned up, and the whole thing sits untouched for a couple days while the epoxy dries and cures.
July 2, 2008
The strake looked like a noodle in a couple places after everything dried, including several liberal coats of penetrating epoxy. The problem was ameliorated a bit by attaching lengths of 2 X 2, thereby straightening the plank. Note the wires that are attached to turnbuckles below, enabling a constant downward pull on the plank to keep it in just the right place.
July 6, 2008
The next strake is made the same way the garboard strake was. Here's a method of cutting the strakes out of the planks on the table without cutting into the table: clamp the plank to the table with an intervening batten. Remove clamps as you come to them, and repace the one behind you. That way, everything stays stable, and you end up with a pair of nicely roughed-out strakes.
July 8, 2008
The strake is clamped on to make sure that the shape is correct, and that everything lines up right. Minor adjustments to the shape can be made, then the strakes are put together, and a couple of mirror-image exact copies are planed out with smooth and gentle curves. The overlap at the ends are cut in with a rabbet plane using this simple jig.
July 11, 2008
Always a milestone, a strake is glued on. After the epoxy dries, and various holes and cracks filled, sharp-bladed tools are used to plane and scrape everything smooth and square.
July 14, 2008
Now, we've got some momentum going. The scarfing, laying out, and shaping of the starkes are going well. The next strake gets shaped fairly quickly. Here's a slick jig that holds the strake pair upright and firmly on the workbench, where a much better job can be done of shaping the curves.
. . . . time passes. Jim gets distracted for several weeks . . .
August 22, 2008
Well, no. Actually, the method shown on the right, where the strake pair are clamped flat on a batten and planed with a block plane laying on its side is the way to go. This not only generally works better, it is faster and simpler to set up.
. . . . back to work, and the rest of the strakes go quickly as shown below. . .
August 22 - September 5, 2008
Each strake gets added . . .
one by one . . .
until you have a hull.Clean it up a bit and give it a good soaking with penetrating epoxy.
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May 15, 2008
For this project, Jim decided to use a laser level, instead of a string, to define the base line. Everything lines up on the baseline, and the offsets in the plans indicate where each station mould is positioned in reference to this baseline. It was thought that setting up a laser level on an adjustable stand could make measuring accuracy better, and would not get in the way like a string does.
It turns out that the laser level was of limited utility, due to the difficulty of lining it up properly. It was very sensitive to the wind, and had to be realigned frequently.
The trade-off was improved accuracy and ease of measuring and marking.
A rigid frame is constructed from 2 X 6" lumber. Since the boat is 20' long, a rectangular frame with short legs was constructed that is over 20' long and is 30" wide. It was chosen to use five station moulds, but offsets for nine are in the plans; the obvious choices are numbers 1, 3, 5, 7, and 9. Station moulds, stem- and stern-posts were lofted and cut out well ahead of time. The distances between the station moulds were carefully measured and marked, then the moulds were attached to the frame. One has to be willing to attach, then remove and realign in order to get everything set up straight and square, with the moulds centered and the proper distance below the baseline. Once the station moulds are securely in place, the stem and stern are attached.
May 21, 2008
The keel, or bottom of the boat is laid on and should fit easily into the notches that have been carefully cut into the station moulds. These had previously been measured with as much precision as possible, then cut. In this case, a local piece of Douglas fir was available that was fairly clear, locally cut and milled, then air dried for a few years. The piece was cleaned up, cut and planed to the correct demensions, then shaped - again from measurements available on the plans. The bottom is glued to the stem and stern posts with epoxy. The joint will be strenghthened by the first plank - the garboard, so the joint does not need any extra fastening. Battons are now placed at the marks on the station moulds that determine the edges of the planks. One wants smooth, "fair" lines with the proper spacing, so defining them with battons helps visualize the shape of the plank. If you have laid out and cut the station moulds accurately, fair lines should correlate with the marks on the station moulds.
One more last careful set of adjustments in the set-up now occurs. This is where the laser level comes in handy. Using the marking guage and ruler, a center line is drawn on the bottom, the heights of the station moulds and bottom are adjusted, and everything squared up and secured in place. The measurements can be done with a fair amount of precision using this technique.
May 27, 2008
The bottom is now beveled. The angle of the bevel goes from just a few degrees in the center of the boat, and becomes quite acute at the stem and stern. This is what gives the boat such a clean entry and no turbulence aft. Using the batten at the end of the first plank, the plane of the garbord is established. Using a straightedge, the intersection of the plane of the garboard with the bottom plank can be marked. A power planer is then used to plane this complex curve. A lot of material is removed, but one does not want to remove too much. When the bevel starts coming close to the correct angle, the use of the straightedge can be helpful to define the bevel accurately.
June 4, 2008
Now it is time to start shaping the garboard strake. The rough shape was determined by marking out a spiling batten. It was found that a 6 3/4" plank will make the nearly straight garboard. It will be made just short of 20' long by scarfing two 8' and a 4' plank. Scarfs are made by pin nailing and clamping a stack of short planks. A 2 1/2" scarf joint is then set up by stacking the planks and pulling each one back exactly 2 1/2". The power planer is used again, this time planing a nice, clean taper into the stack of planks. Plywood is easy to get a good scarf, because of the way the layers stand out Getting a clean taper means keeping all the lines exactly the same width.
The planks are then aligned and glued with epoxy, creating two 20' planks. Care in lining up the grain pattern must be included. The planks are then measured and cut according to your favorite method. Excellent descriptions are present in many of the references. Besides being as accurate with the measurements as you can, it is also critical to keep the lines "fair", meaning having a smooth and natural-looking curve. Or straight line, as will be needed for the garboard strake. The lands are at the fore and aft ends of the strakes, where they gradually blend into each other to end smoothly at stem and stern. Excellent instructions on how to cut the lands are present in the references and there are several ways to do them, but here we will be cutting them with a rabbet plane.
June 12, 2008
Shaping the 20' planks and getting them glued into place is a challenge. At this point, it would be good to have several helpers. Slow epoxy is used to give the workers plenty of time to line up the planks perfectly. The garboard is screwed to the bottom as shown on the right, while the plank is held in place at each of the stations as shown on the left.
After the epoxy has dried, the screws and the clamps are removed. Some planing can be done with the plank to adjust the fairness of the first line, but it didn't seem to be necessary here.
After the epoxy has dried, the screws and the clamps are removed. Some planing can be done with the plank to adjust the fairness of the first line, but it didn't seem to be necessary here.
June 22, 2008
The bottom is planed flat, then the outer edge of the garboard is planed to recieve the next strake. A good way to do this accurately is to clamp a batten along the outer edge of the next strake and using a simple device like that shown on the left, the proper angle can be planed so that the next strake will land flat.
Following the dimensions on the plans, A bottom plate is shaped. The origional plans called for putting a rabbet into the bottom board, into which the garboard - perfectly shaped - fit. This feat is out of reach of this builder, so in this case, a 3/8" "bottom plate" is shaped and glued on, giving the craft the appearance and functionality of the origional design. Some local chincopen was available; it was planed to 3/8", rough cut with a skill saw, then planed to shape.
Following the dimensions on the plans, A bottom plate is shaped. The origional plans called for putting a rabbet into the bottom board, into which the garboard - perfectly shaped - fit. This feat is out of reach of this builder, so in this case, a 3/8" "bottom plate" is shaped and glued on, giving the craft the appearance and functionality of the origional design. Some local chincopen was available; it was planed to 3/8", rough cut with a skill saw, then planed to shape.
June 28, 2008
The bend at the ends of the bottom require saw kerfs to be made. Kerfs were cut an inch apart and half the thickness of the board. After another good sanding, the bottom was slathered with epoxy with same to the bottom plate, and the plate was tacked to the bottom with some pin nails and a screw at each end. The curved ends were clamped to the stem. Drips were cleaned up, and the whole thing sits untouched for a couple days while the epoxy dries and cures.
July 2, 2008
The strake looked like a noodle in a couple places after everything dried, including several liberal coats of penetrating epoxy. The problem was ameliorated a bit by attaching lengths of 2 X 2, thereby straightening the plank. Note the wires that are attached to turnbuckles below, enabling a constant downward pull on the plank to keep it in just the right place.
July 6, 2008
The next strake is made the same way the garboard strake was. Here's a method of cutting the strakes out of the planks on the table without cutting into the table: clamp the plank to the table with an intervening batten. Remove clamps as you come to them, and repace the one behind you. That way, everything stays stable, and you end up with a pair of nicely roughed-out strakes.
July 8, 2008
The strake is clamped on to make sure that the shape is correct, and that everything lines up right. Minor adjustments to the shape can be made, then the strakes are put together, and a couple of mirror-image exact copies are planed out with smooth and gentle curves. The overlap at the ends are cut in with a rabbet plane using this simple jig.
July 11, 2008
Always a milestone, a strake is glued on. After the epoxy dries, and various holes and cracks filled, sharp-bladed tools are used to plane and scrape everything smooth and square.
July 14, 2008
Now, we've got some momentum going. The scarfing, laying out, and shaping of the starkes are going well. The next strake gets shaped fairly quickly. Here's a slick jig that holds the strake pair upright and firmly on the workbench, where a much better job can be done of shaping the curves.
. . . . time passes. Jim gets distracted for several weeks . . .
August 22, 2008
Well, no. Actually, the method shown on the right, where the strake pair are clamped flat on a batten and planed with a block plane laying on its side is the way to go. This not only generally works better, it is faster and simpler to set up.
. . . . back to work, and the rest of the strakes go quickly as shown below. . .
. . . . time passes. Jim gets distracted for several weeks . . .
August 22, 2008
Well, no. Actually, the method shown on the right, where the strake pair are clamped flat on a batten and planed with a block plane laying on its side is the way to go. This not only generally works better, it is faster and simpler to set up.
. . . . back to work, and the rest of the strakes go quickly as shown below. . .
. . . . back to work, and the rest of the strakes go quickly as shown below. . .
August 22 - September 5, 2008
Each strake gets added . . .
one by one . . .
until you have a hull.Clean it up a bit and give it a good soaking with penetrating epoxy.