to RECANVAS an old CANOE? Try a new simpler method
have an old wood canoe...the wood is in fair shape but the canvas
has had it. There is no way that you can imagine stretching new
canvas with a come-along or some other brute force to fit the
hull curves. A modern material works like shrink wrap and presto
a rejuvenated boat!
with heat shrink Dacron fabric has these advantages:
Prepare the hull:
Before starting I want to mention that there is a really
good book about Canoe Restoration by: Jerry Stelmok & Rollin
Thurlow. There is a lot more to it than simply putting on the "canvas".
the rub rails, keel and brass trim cutwaters. (You will re-use these
or need them to make patterns). Strip off the old canvas, gently
so as to not pry off any hull planking. Repair or replace any damaged
wood. West System epoxy or "Git"-Rot can be used to toughen
any punky or split areas.
At this point
it might be worth your while to strip off the interior varnish and
re-do it. There are paint removers that work by hosing with water
to remove the chemically loosened residue. Tighten any loose nails
that might be protruding; smooth all irregularities and apply a
coat of varnish on the outside.
Nothing very exotic just normal household things...screw driver
etc. and household iron and scissors. Best get a cheap second hand
iron at Dots Good Deals, second hand shop. Do not use the wife’s
best iron! It will get gooped up on the bottom and is hard to clean.
Measure the hull girth amidships to be sure that one piece
of fabric 72" wide will be enough material to do it in one
piece; otherwise it will need to be joined at the center line. Now
measure along the gunwale and add a half yard for overlaps and that
is what you need to purchase.
The Dacron has
a fine texture that will not hide bumps so examine all of the hull
for imperfections and make them fair. Because the fabric is heat
shrunk, it will bridge over hollows. That is OK for small dimples;
however large depressions should be filled with wood dough or a
mix of fine sawdust and epoxy.
is applied with adhesive transfer tape along the gunwales and stems,
which eliminates tacks. Actually it is hot melt glue in tape form
and that is where we start.
2—SET THE HEAT
To answer the most obvious question: Can you use a heat
gun? the answer is a resounding NO! The reason is that you would
not have any idea of what temperature is being applied. Another
reason is that the hot melt glue tape requires that pressure be
applied as it is used.
iron by setting it on a scrap corner of the Dacron and slowly raise
the thermostat till the fabric starts shrinking. That is about 225-250
Deg. (note this setting) This is one of the features that is forgiving.
The Dacron starts to melt at about
425 Deg. and
gives off a warning with wafts of steam coming off the surface first.
That is over 100 degrees safety margin.
You might care
to do some experimenting with the actual heat setting. In which
case you can make up a rig with a roll of paper towels and a candy
thermometer. Squash the roll a little to make a sort of nest with
the business front end of the iron and set the thermometer bulb
under the iron and let it sit until the temperature stabilizes make
a reading. Now you see how to do it so mark settings on the iron
- 225 degrees
-starts to soften
- 250 "
- 350 "
- 375 "
-do not exceed
- 425 "
-begins to melt
is good for marking the iron)
While you are
setting the temperature it is a good time to clean the bottom of
the iron of any residual crud. This done by setting to the 350 degree
temperature and scrub in a vigorous manor on some clean white paper
or scrap Dacron. If stains rub off, it needed the cleaning.
This glue has
a keeper paper on one side, the textured side is the adhesive. All
that you have to do is hold the tape in place and press the tip
of a hot iron, set @ 225 deg. on it in spots every 2". It will
melt and stick to the wood. Now remove the keeper and it is ready
for the Dacron. It is a good idea to a test on a short scrap piece
With the boat
upside down on saw horses or whatever, you need to apply the HeatnBond
tape along the bottom edge of the gunwale plank, around the edge
of transom (if a square stern), keelson and at the stem. This means
both sides and front face (under where the cut water goes)
3—APPLY THE DACRON
Now drape the Dacron on the inverted hull; then even it
up in the center. Next twist it so that it is diagonal on the hull
as much as possible without any edges coming up short at the stem.
You should maintain a 3-4" overlap from all edges.The next
trick is important and it helps to have a helper. Pull on the fabric
from stem to stem on the diagonal of the cloth.You will observe
a stretch on the bias that starts to fit the compound curvature.
Clamp it in place on the stems. Pull it down on on each side in
the center and clamp it to the Gunwales.
With the iron
still set at the shrinking temp. start ironing the Dacron onto the
HeatnBond tape along the Gunwales. Work in the center and go back
and forth from side to side. Press firmly, with the iron and hold
it in one spot for about 3 seconds until the adhesive shows a translucency
and feels waxy. Now be sure that you do some shrinking at the same
time. Here it may take some heat adjustment because it is important
to shrink as you go. It must lay flat with no overlaps so shrink
plenty as you go. Always pull the excess fabric edge down; never
towards the ends as you iron. It is right here that you can see
why you must heat with an iron, not a heat gun! Don’t worry
about any wrinkles or puckers along side of the gunwale, you will
get them later. Just keep pulling down as much as possible. There
is a temptation to pull towards the end of the boat to get rid of
a wrinkle. resist that urge it only makes a larger wrinkle ahead
when you get to about 6" from the ends. Remember that I told
you that these materials are very forgiving. The tape glue has very
good shear strength and that is how it is loaded on the boat; however
it has low peel strength. Now is the time to check your work. If
something doesn’t look right you can peel it off in any area
and re-do it. It may need some more tape.
At this point
you can trim off the excess material on each side of the stem, leave
4-6" extra for overlap. Slit the material on the center line
to about 1" short of the point where the curvatur
on one side and front face of the stem starting at the end of the
slit. Adhere it to the side and front face. Trim off the excess
so that it is not lapping on the far side. As you approach the gunwale,
glue that last 6" to close the gap with glue all around.
FABRIC AT STEM
Add some more
heat tape at the stem to cover the Dacron where the second side
will land, just the stem front face. Now complete the second side
the same as the first and trim off the Dacron to the edge of the
4—SHRINK THE SKIN
is the moment you have been waiting for! Shrink all over the hull
surface. Do not heat stick it to the keel until it is tight all
over. It very important to remember to keep the iron away from the
areas of the heat tape (gunwale and stem) because if you re-heat
there while the shrinking tension has been applied, it will pull
loose. Because the gunwale is on the bottom edge it is easy to slip
and go too low. So I suggest that you clamp a piece of wood (like
the rub rail) in place as a guard while you work close to the gunwale.
One thing to
watch out for is to not run the iron on top of a wrinkle and press
a fold...they are hard to remove. Some patience with the tip of
the iron will get rid of the fold. You will find that if you sweep
the iron lightly over the flat areas, wrinkles will pull out of
other places. Don’t over do shrinking; just do it enough to
get it smooth. Work in a well lit area and look at reflections on
the skin from different angles to spot irregularities. Now set the
HeatnBond tape along the keelson.
This is is an overlay piece of fabric to reinforce the Stem...not
necessary but a nice touch. Pinking Shears really should be used
here. Cut a piece of scrap fabric, on a 45 deg. bias, about 4"
wide and about 1" longer than the overlap area at the stem.
Make a half circle round on one end. For appearance sake it is quite
important that it have pinked edges. Stick a strip of adhesive tape
down the stem, starting with a 1" overlap on the slit cut.
Now adhere the
doubler in one small 1/2" dot at the beginning of the tape.
Next you pull on the other end and observe how it stretches on the
bias to fit flat against a compound curve. Keep it centered as you
pull it down and iron it to the stem front face.
Mark the edges
with masking tape. Then one side at a time, carefully lift the fabric
back so that you can apply some heat tape. Cut patterns from sheet
stock. Lay the cloth back in place and set the adhesive with the
iron at a no shrink setting.
5—SEALING THE DACRON
The simplest treatment is a couple of coats of Moore's
ext.Acrylic latex paint with Penetrol additive. Let it dry thoroughly
at least a week. Any sanding should be done with 320 grit paper
and then very lightly. If there are any bumps or pimples about two
passes even with 320 grit will cut through the fabric and make a
small hole. Another option on sanding is to stay away from sandpaper
altogether. Use SCOTCH BRITE or BRILLO, Nylon scrubber pads. They
work quite well for sanding imperfections in the varnish and are
a lot safer than sand paper.
can be toughened with a couple of overlay coats of exterior /marine
water base varnish. (I suggest Aqua Coat)
A Silver Coat?
This is an aircraft terminology and is all about UV Degradation.
I have said that the Dacron will not rot. That is true but UV will
degrade unprotected fabric at a rate of 70% of its strength in less
than one year. If you store the boat in a barn or keep it covered
with a black poly tarp there is no problem.
The best solution
is to start the sealing finish with three silver coats. This is
done with aluminum filled paint.(Rust Oleum) It is aluminum paste
flakes that are the pigment. The flakes reflect the UV rays and
provide an effective barrier that protects the fabric. Three coats
is probably enough however; I suggest that you make up a square
test panel of some 2x2 stock frame and fabric cover it. The trick
is to hold a 60 watt bulb behind a painted panel. When you can’t
see the light show through it has enough paint
One word of
caution about the oil based finishes, they have a tendency to loosen
and lift the HeatnBond adhesive. Don’t lather it all over
the adhesive areas. Brush lightly will probably be OK on the 1st
When you replace
the exterior parts, set them in bedding compound (3M 5200 is recommended)
or thickened epoxy. This is to avoid leaks into the woodwork.
When you complete the covering be sure to squirrel away
some of the scrap Dacron fabric. At some point you may damage the
skin with a hole, rip or tare. Patches are simple to make. Iron
on some HEATnBOND tape to one side of a piece of fabric by completely
covering it. Now cut out a patch that will overlap with a one inch
border the damaged area. (pinking shears are recommended here).
Iron the patch in place with the iron set at the No Shrink Heat
Setting. Add finish as done previously,
"The Wood & Canvas Canoe" By Jerry Stelmok
& Rollin Thurlow
Tilbury House Publisher
Aqua Coat from:
Rust Oleum Aluminum
11 Hawthorn Parkway
Vernon Hills, IL 60061
51Chestnut Ridge Road
Montvale, NJ 07645.
There is a very
fancy web site: www.benjaminmoore.com It even has street maps to
help you find your local dealer. You can also call 1-800-344-0400
melt adhesive transfer tape) 10 Yd. Roll @ $2.00 + P&H
Dacron —3.7 Oz., 70 or 72" width @ $8.00/ Yd. + P&H
Associates 50 Haskell Road Westport Maine 04578