Hi,

We had a splendid weekend in the Ardennes until I made a mistake.
How can I repair a royalex canoe after a serious crash?

Cheers,
Alan.

Alan wrote:

We had a splendid weekend in the Ardennes until I made a mistake.
How can I repair a royalex canoe after a serious crash?

Up to a certain point, I'm pretty sure that you can add a layer of
glassfiber (or kevlar etc.) over a worn spot or crack. After that, it's
time for a new boat.

What did you paddle in the Ardennes?

--
Wilko van den Bergh Wilkoa t)dse(d o tnl
Eindhoven The Netherlands Europe
Look at the possibilities, don't worry about the limitations.
http://wilko.webzone.ru/

If it's not torn, just creased and twisted, heat will do wonders. Leave it
in the sun during summer, and it will help a lot. Also heat gun will help.
Don;t get it too hot... Heat and time are best. If it's torn, sanding thru
the vynal a fiberglassing with epoxy will help. Don't make to patch too
thick, as it has to flex with the plastic.

"Alan" wrote in message
om...
Hi,

We had a splendid weekend in the Ardennes until I made a mistake.
How can I repair a royalex canoe after a serious crash?

Cheers,
Alan.

Tell us more about the damage. There are four levels of repair, so we need
to know how badly you crashed.

1) for folds, creases and dents where the boat is still intact, but twisted
all up: initially, leaving it in the warm sun will let the foam core expand
and a lot of damages will go away! Beyond that, a heat gun (careful,
careful: no blisters on the boat wanted!) will encourage the foam core to
expand and you can gently urge the boat back into shape. You will need to
replace all the broken hardware, but the boat will spring back into its
form.

2) For minor tears and abrasions through the skin: a coat of paint or a
fiberglass patch will work, but you will need to heat the surface to prep
it. If the patch is over a 'flex point', such as the chine, you might
consider gluing a rubber patch on instead, as the glass will quickly break
off. End plates are almost always Kevlar.

3) For major tears, some astute folks actually heat and peel the surface
skin back, cut out some of the foam core and replace it with a graft, then
reglue the skin over it. This is a very difficult, but permanent repair, and
in truth I have never seen it done but only heard about it. For major tears,
I usually have sewn the tear shut with parachute cord, then laid a big old
glass patch over it, inside and out.

4) For jagged tears with missing pieces, in flex points that will recieve
much abrasion and impact (such as the front chine, or the side below the
gunnels amidships): toss it out.

--riverman

Alan,

I've rebuilt a couple dozen Royalex canoes, most of which were
dumpster-ready when I got them.

Pretty much if you still have all of the pieces of the hull it can be
put right.

Send me an e-mail and describe the damage, and I can walk you through
what you'll need to do to repair it.

Mike McCrea

(Alan) wrote in message . com...
Hi,

We had a splendid weekend in the Ardennes until I made a mistake.
How can I repair a royalex canoe after a serious crash?

Cheers,
Alan.

"riverman" wrote in message ...

"Alan" wrote in message
om...

Tell us more about the damage. There are four levels of repair, so we need
to know how badly you crashed.

1) for folds, much deleted

Hey Riverman, sure seems like you've had some experience with this. I have a related question. My Royalite Canoe which is a 13'
footer has begun oil canning. It's got a flat bottom, hard chines, and a bit of tumblehome. I figured the oil canning could be
stopped if I can make a shallow arch or V-bottom configuration in cross-section. So here's what I thought to do, first mount a
section of plywood lengthwise on a strongback, then invert and center the canoe over the plywood so that it is resting on the
interior deck along the length of the hull. Then put several straps over the canoe and stake to the ground with enough force to
cause a curvature in cross-section. Then apply some heat ( don't think a hair dyer would do ) to make the hull assume the desire
curvature. I'm a bit woried about how symmetrical the result will be but if I monitor the shape and adjust straps as I go it should
not get too warped. I'd like to hear some thoughts about this.
Actually, I figure to curve the plywood just a bit for a slight amount of rocker.

Te Canaille

"Te Canaille" wrote in message
news:Zpcoc.138522$f_5.46889@lakeread01...

"riverman" wrote in message
...

"Alan" wrote in message
om...

Tell us more about the damage. There are four levels of repair, so we
need
to know how badly you crashed.

1) for folds, much deleted

Hey Riverman, sure seems like you've had some experience with this. I have
a related question. My Royalite Canoe which is a 13'
footer has begun oil canning. It's got a flat bottom, hard chines, and a
bit of tumblehome. I figured the oil canning could be
stopped if I can make a shallow arch or V-bottom configuration in
cross-section. So here's what I thought to do, first mount a
section of plywood lengthwise on a strongback, then invert and center the
canoe over the plywood so that it is resting on the
interior deck along the length of the hull. Then put several straps over
the canoe and stake to the ground with enough force to
cause a curvature in cross-section. Then apply some heat ( don't think a
hair dyer would do ) to make the hull assume the desire
curvature. I'm a bit woried about how symmetrical the result will be but
if I monitor the shape and adjust straps as I go it should
not get too warped. I'd like to hear some thoughts about this.
Actually, I figure to curve the plywood just a bit for a slight amount
of rocker.

Te Canaille


Hi Te:
Hmm, I don't see an obvious easy solution to this, but what you're
envisioning doesn't look good. I once saw a royalex boat that was too close
to a campfire reach the temperature where it lost its cohesive stability.
The hull suddenly had the consistency of freshly cooked lasagna noodles, and
it was was impossible to hold it in shape with our hands while it cooled and
got rigid. We flopped it down rightside up on the ground, and to this day it
still has a completely flat bottom because of that. If it had landed on a
stick, that would have just gone right through the bottom.

My first thought with your idea is that, since all the force will be focused
on the point where the plywood meets the royalex, when you heat it, all you
are going to do is make a very thin weak spot right along the centerline of
your hull. When OldTown (and others) form a boat from a royalex sheet, it is
completely supported by the mold, so there is no point-pressure anywhere. I
think you'd end up with a long pinch-crease, probably even with holes melted
through in places. And a weak spot precisely where you don't want it.

You would probably have to make a full-support mold, but it would have to
follow the 3-dimensional curvuture of the hull along its entire length. Not
an easy task. Maybe something like digging a shallow pit in exactly the
shape you want the hull, set the boat on it (rightside up), and dump about
20 gallons of boiling water in it? Have some cold water handy to stop the
process when it starts to deform.

Another option is to go the (ugh) Coleman route, and just put a lengthwise
brace on the floor with a center T to hold the oilcan down. My own BlueHole
oilcans like crazy (I think its an artifact of the chines getting tired), so
I just jam an ammocan under the center thwart.

Another option is to shorten the thwarts! You have some tumblehome, but if
you shorten the thwarts, it will make the hull more 'tubular', and reinforce
the bottom. I don't know how much you'd have to do this, though.

Good luck.
--riverman

Riverman :

Thanks for the response and advice. There was some wishful thinking here for an easy solution and I think you're probably right and
reckon I won't fuss with this.

The thing about shortening the thwarts brings up an interesting point. A few years back Mohawk Canoes came out with an adjustable
thwart, mainly for whitewater canoes. The paddler could twist it to shorten or lengthen. I called Daryll and spoke to him about this
and he maintained that shortening the thwart decreased rocker. The canoe in question already has a flat keel-line. What I would like
to do is add a slight amount of rocker to stop the oil canning and increase maneuverability and an arched bottom to increase
secondary stability. I wondering about the memory of Royalite. If I strap ( or add a shortened thwart ) the hull amidships to arch
the bottom for several months would it just bouce back to flat or retain some arch ? My guess is that it would retain some arch for
a while but eventually flatten out. This will be the third canoe I've lost to oil canning and it'd be great to figure out a
solution.

Te Canaille

"riverman" wrote in message ...

"Te Canaille" wrote in message
news:Zpcoc.138522$f_5.46889@lakeread01...

deletions

Hi Te:

My first thought with your idea is that, since all the force will be focused
on the point where the plywood meets the royalex, when you heat it, all you
are going to do is make a very thin weak spot right along the centerline of
your hull. When OldTown (and others) form a boat from a royalex sheet, it is
completely supported by the mold, so there is no point-pressure anywhere. I
think you'd end up with a long pinch-crease, probably even with holes melted
through in places. And a weak spot precisely where you don't want it.

You would probably have to make a full-support mold, but it would have to
follow the 3-dimensional curvuture of the hull along its entire length. Not
an easy task. Maybe something like digging a shallow pit in exactly the
shape you want the hull, set the boat on it (rightside up), and dump about
20 gallons of boiling water in it? Have some cold water handy to stop the
process when it starts to deform.

Another option is to go the (ugh) Coleman route, and just put a lengthwise
brace on the floor with a center T to hold the oilcan down. My own BlueHole
oilcans like crazy (I think its an artifact of the chines getting tired), so
I just jam an ammocan under the center thwart.

Another option is to shorten the thwarts! You have some tumblehome, but if
you shorten the thwarts, it will make the hull more 'tubular', and reinforce
the bottom. I don't know how much you'd have to do this, though.

Good luck.
--riverman

Te,

Re-molding the basic hull shape of a Royalite canoe seems to me an
iffy proposition at best. I don't know anyone who has this as
dramaticaly as you propose, but I can think of quite a few things that
could go wrong.

A friend with a Mohawk Nova 16 on R-84 was unsatisfied with the
oilcanning of that hull (which was very noticable). His solution was
to steam bend some halfround hardwood molding and make a couple of
ribs which run from gunwale to gunwale, glassing them in place with
epoxy resin and fiberglass tape.

It helped quite a bit with the oil canning, didn't add much weight and
doesn't look too bad. My concern with his approach was the longevity
of the fix, thinking that the rib/glass would seperate from the hull
on an impact or when sliding the loaded boat over a barely submerged
log.

So far, so good - although the canoe sees mostly easy water and gentle
use.

Mike

"Te Canaille" wrote in message
Hey Riverman, sure seems like you've had some experience with this. I have a related question. My Royalite Canoe which is a 13'
footer has begun oil canning. It's got a flat bottom, hard chines, and a bit of tumblehome. I figured the oil canning could be
stopped if I can make a shallow arch or V-bottom configuration in cross-section. So here's what I thought to do, first mount a
section of plywood lengthwise on a strongback, then invert and center the canoe over the plywood so that it is resting on the
interior deck along the length of the hull. Then put several straps over the canoe and stake to the ground with enough force to
cause a curvature in cross-section. Then apply some heat ( don't think a hair dyer would do ) to make the hull assume the desire
curvature. I'm a bit woried about how symmetrical the result will be but if I monitor the shape and adjust straps as I go it should
not get too warped. I'd like to hear some thoughts about this.
Actually, I figure to curve the plywood just a bit for a slight amount of rocker.

Te Canaille

riverman wrote:

Hmm, I don't see an obvious easy solution to this, but what you're
envisioning doesn't look good. I once saw a royalex boat that was too close
to a campfire reach the temperature where it lost its cohesive stability.
The hull suddenly had the consistency of freshly cooked lasagna noodles, and
it was was impossible to hold it in shape with our hands while it cooled and
got rigid. We flopped it down rightside up on the ground, and to this day it
still has a completely flat bottom because of that. If it had landed on a
stick, that would have just gone right through the bottom.

Sounds like Royalex is a tradename for polypropylene. Is it?
Polypropylene has a very low melting temperature, but is otherwise
strong, lightweight and durable.