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The Strong Back
The strongback is simply the temporary jig used to hold the forms and stems in place while you build
your hull. There are many different ways to accomplish the function of a strongback. You need a
strongback to build a 14’ canoe or a 30’ sailboat. Even though they perform the same function, they will
obviously be built differently as they have different requirements.
your hull. There are many different ways to accomplish the function of a strongback. You need a
strongback to build a 14’ canoe or a 30’ sailboat. Even though they perform the same function, they will
obviously be built differently as they have different requirements.
Builders will have differing opinions even on a strongback for a
canoe or kayak and when all is said and done, as long as the
strongback allows for the building of the hull and performs the
function of holding the forms in place then it will probably work
fine. The strongback described here is simple, versatile, and
inexpensive and has been used to build hundreds if not
thousands of boats around the world. This strongback is a
simple box sitting on top of a couple of small tables on wheels.
The strongback can be made from dimensional lumber or from
ripped pieces of plywood, however it is very important that your
strongback is straight and square so if you can’t find straight
dimensional lumber then ripped plywood is the way to go.
canoe or kayak and when all is said and done, as long as the
strongback allows for the building of the hull and performs the
function of holding the forms in place then it will probably work
fine. The strongback described here is simple, versatile, and
inexpensive and has been used to build hundreds if not
thousands of boats around the world. This strongback is a
simple box sitting on top of a couple of small tables on wheels.
The strongback can be made from dimensional lumber or from
ripped pieces of plywood, however it is very important that your
strongback is straight and square so if you can’t find straight
dimensional lumber then ripped plywood is the way to go.
The dimensioning of a strongback for a canoe or kayak is fairly straightforward. It should be a few inches
shorter than the boat to be built and wide enough to support the forms. That simply means if you are
building a 16’ canoe then you will want your final strongback to be about 6” or so shorter than that so that
the stem forms will overhang the strongback on either side. Having this overhang will allow you to strip
near the sheer without your strips bumping into the deck of the strongback.
You will also note that this particular strongback is built in three sections. I have a couple of reasons for
that. First because finding extra long lengths of wood to build it in one piece is unnecessarily difficult and
second and more important to me is this design is able to expand and contract in size as needed. So if
the percentages are high that you will be building another boat that will vary in length, this is the design
for you.
shorter than the boat to be built and wide enough to support the forms. That simply means if you are
building a 16’ canoe then you will want your final strongback to be about 6” or so shorter than that so that
the stem forms will overhang the strongback on either side. Having this overhang will allow you to strip
near the sheer without your strips bumping into the deck of the strongback.
You will also note that this particular strongback is built in three sections. I have a couple of reasons for
that. First because finding extra long lengths of wood to build it in one piece is unnecessarily difficult and
second and more important to me is this design is able to expand and contract in size as needed. So if
the percentages are high that you will be building another boat that will vary in length, this is the design
for you.
As you can see from the picture, once each side is built to the right
size, you simply slip the connector piece between the two and set
six screws in each side to hold them together. Be careful with the
length of the screws so that you don’t get caught on them if you
have to work under the strongback.
The tricky part to this operation is holding everything in line and at
the same level in order to put them together. The rolling table design
used here makes this a simple matter. If it is your intention to use
some other method to support your strongback then you will likely
have to find a long straight section of bench or a flat floor to get this
done. It is very important that when all of the pieces are together,
they form a long straight box. It will make leveling and aligning the
forms much easier to accomplish.
Once the box is complete, it is a simple matter of putting a deck on
the strongback. I choose to make my decks hang over the box
about an inch on either side in case I want to use them to hold
temporary bungee chords strapped over the hull during stripping.
Setting a screw just under the overhang makes a great place to hook
your straps. If you are using dimensional lumber, use extra screws
along the edges to make sure that the board will stay in place and
not succumb to cupping or warping during the building process.
We will talk about using a chalk line to make a centerline on your
strongback deck, however if you have a table saw then you may
want to consider putting the deck on the table saw and using a thin
kerf blade, make a cut down the center of the deck no deeper than
1/8”. This works well and quickly gives you a centerline to work
with, however be sure that if you are using a two-piece deck that the
lines meet up and are straight from one end to the other. This is
easily accomplished by pulling a string from one end to the other
while attaching the second half of the deck.
size, you simply slip the connector piece between the two and set
six screws in each side to hold them together. Be careful with the
length of the screws so that you don’t get caught on them if you
have to work under the strongback.
The tricky part to this operation is holding everything in line and at
the same level in order to put them together. The rolling table design
used here makes this a simple matter. If it is your intention to use
some other method to support your strongback then you will likely
have to find a long straight section of bench or a flat floor to get this
done. It is very important that when all of the pieces are together,
they form a long straight box. It will make leveling and aligning the
forms much easier to accomplish.
Once the box is complete, it is a simple matter of putting a deck on
the strongback. I choose to make my decks hang over the box
about an inch on either side in case I want to use them to hold
temporary bungee chords strapped over the hull during stripping.
Setting a screw just under the overhang makes a great place to hook
your straps. If you are using dimensional lumber, use extra screws
along the edges to make sure that the board will stay in place and
not succumb to cupping or warping during the building process.
We will talk about using a chalk line to make a centerline on your
strongback deck, however if you have a table saw then you may
want to consider putting the deck on the table saw and using a thin
kerf blade, make a cut down the center of the deck no deeper than
1/8”. This works well and quickly gives you a centerline to work
with, however be sure that if you are using a two-piece deck that the
lines meet up and are straight from one end to the other. This is
easily accomplished by pulling a string from one end to the other
while attaching the second half of the deck.
If like most people you are working in limited space and
there is a good chance that you are sharing that space with
the rest of the family you will find the roll around
strongback supports to be invaluable. There are two very
good reasons to go the extra mile and build these. First
your space is limited and you will need to roll the boat out
of the way to do another task or perhaps you only have
room to work on one side of the boat so you will need to
move it back and forth. Second and more common is you
have limited time to build the boat, however the space you
are building in is used for other things.
there is a good chance that you are sharing that space with
the rest of the family you will find the roll around
strongback supports to be invaluable. There are two very
good reasons to go the extra mile and build these. First
your space is limited and you will need to roll the boat out
of the way to do another task or perhaps you only have
room to work on one side of the boat so you will need to
move it back and forth. Second and more common is you
have limited time to build the boat, however the space you
are building in is used for other things.
In either case, it is a handy feature to be able to roll the boat into a corner out of the way when you
need to. Building these supports is easy, and quick. All it requires is a 2’ X 4’ piece of ¾” plywood
(the cheap stuff will do here) and a couple of 2” X 4” ‘s. The most expensive part will be the wheels.
You won’t be supporting much weight so there is no need to get very large heavy weight wheels.
No one is more sympathetic than I when it comes to the trials and tribulations of trying to rip a large
piece of plywood when there is not a second pair of hands to help. That is the reason for the
dimensions shown here. Most stores will sell “handy panels” already cut for you. At the very least
they will cut in store to your desired dimensions. This also makes getting them home easier if you
don’t own a pickup truck.
During the video you will probably notice that the strongback is flanked on either side by a 2” X 4”.
This is done so that when you move the boat around it will move as one unit. Once the strongback
is sitting on your two supports, simply cut short pieces and screw them in on both sides of the
strongback. This will also avoid the unlikely but possible catastrophe of the strongback sliding, or
pivoting off the supports during the building process.
need to. Building these supports is easy, and quick. All it requires is a 2’ X 4’ piece of ¾” plywood
(the cheap stuff will do here) and a couple of 2” X 4” ‘s. The most expensive part will be the wheels.
You won’t be supporting much weight so there is no need to get very large heavy weight wheels.
No one is more sympathetic than I when it comes to the trials and tribulations of trying to rip a large
piece of plywood when there is not a second pair of hands to help. That is the reason for the
dimensions shown here. Most stores will sell “handy panels” already cut for you. At the very least
they will cut in store to your desired dimensions. This also makes getting them home easier if you
don’t own a pickup truck.
During the video you will probably notice that the strongback is flanked on either side by a 2” X 4”.
This is done so that when you move the boat around it will move as one unit. Once the strongback
is sitting on your two supports, simply cut short pieces and screw them in on both sides of the
strongback. This will also avoid the unlikely but possible catastrophe of the strongback sliding, or
pivoting off the supports during the building process.