On 14 Mar 2005 19:02:10 -0800, "BCITORGB"
wrote:

(snipped)

Hmmmm... now you've got me worried. Just to check, do you have
expertise re van doors? I don't, hence my worry. I wouldn't have
thought that approx 50 pounds at the mid-point of the door frame would
be too much for the door-to-frame connection to withstand. However, I
haven't a clue. Does anyone else out there have any opinions?

Cheers,
Wilf

Only a few damaged car doors. Not by boats, but by kids. The doors
did stay on as long as they were kept locked closed and tied to the
frames if necessary, but that mean exiting through the car window,
which could be undignified, especially in a skirt or dress.

Look at what holds your doors on. In a car it's two hinges. Stress
compounded with leverage is probably not a good thing for hinges. Look
at how many square inches of hinge there are. Look at the door.

You may decide to just lean it against the top and lever it that way
until you cobble up or buy a rack extender. Paint scrapes just need
some repair (or, in my case, some ignoring), but a damaged door is
more expensive in time and money and safety.

Cyli
r.bc: vixen. Minnow goddess. Speaker to squirrels.
Often taunted by trout. Almost entirely harmless.

http://www.visi.com/~cyli
email: lid (strip the .invalid to email)

Cyli says:
================
Look at what holds your doors on. In a car it's two hinges. Stress
compounded with leverage is probably not a good thing for hinges. Look
at how many square inches of hinge there are. Look at the door.

You may decide to just lean it against the top and lever it that way
until you cobble up or buy a rack extender. Paint scrapes just need
some repair (or, in my case, some ignoring), but a damaged door is
more expensive in time and money and safety.
=====================

I take your point.

Last yesterday PM I was already at a hardware scouting out the
materials to cobble together a rack extender. My initial thoughts are
electrical conduit -- 2 different diameters. I would clamp (using
something like hose clamps) the larger diameter conduit to the front
roof rack crossbeam. Then, the other piece of conduit would slide in
and out as needed; held in place (either in or out) by a cotter pin or
some such gismo.

My only concerns a will I have enough of the smaller diameter
conduit extended to hold the kayak (approx 24" - but I'll need some
slack as the back of the kayak is pulled around, so let's say 28"). OR
If too much of the smaller conduit is extended, will I still have (a)
"stability" due to the "play" between the two pieces of conduit and (b)
since I'm no electrician, at what point (weight of kayak) can I expect
the conduit to bend?

Any thoughts? Improvements? Recommendations?

Cheers,
Wilf

BCITORGB wrote:
Cyli says:
================
Look at what holds your doors on. In a car it's two hinges. Stress
compounded with leverage is probably not a good thing for hinges.
Look
at how many square inches of hinge there are. Look at the door.

You may decide to just lean it against the top and lever it that way
until you cobble up or buy a rack extender. Paint scrapes just need
some repair (or, in my case, some ignoring), but a damaged door is
more expensive in time and money and safety.
=====================

I take your point.

Last yesterday PM I was already at a hardware scouting out the
materials to cobble together a rack extender. My initial thoughts are
electrical conduit -- 2 different diameters. I would clamp (using
something like hose clamps) the larger diameter conduit to the front
roof rack crossbeam. Then, the other piece of conduit would slide in
and out as needed; held in place (either in or out) by a cotter pin
or
some such gismo.

My only concerns a will I have enough of the smaller diameter
conduit extended to hold the kayak (approx 24" - but I'll need some
slack as the back of the kayak is pulled around, so let's say 28").
OR
If too much of the smaller conduit is extended, will I still have (a)
"stability" due to the "play" between the two pieces of conduit and
(b)
since I'm no electrician, at what point (weight of kayak) can I
expect
the conduit to bend?

Any thoughts? Improvements? Recommendations?

Cheers,
Wilf

Hey Wilf, You never said that I can find, what sort of roof rack do you
have? Is it a Commercial unit? If so, most of them have some sort of
extender system already made. No point in reinventing the wheel.

The problem with electrical conduit is two fold. First it is steel and
would begin to get nasty fast when exposed to salt water. Secondly, it
is designed to bend, which is great in some projects, but you would not
want it to decide to bend when you have the kayak on it and lifting
other end. It would result in a loud crash, and possibly a broken boat
or twisted back as you try to keep the loud crash from happening. Any
of these scenarios being bad.

I think you will also find that the commercial extender systems do not
extend as far as you are thinking like up to 28". So, though they use
extruded, hardened Aluminum, which is amazingly strong, they only go
out like maybe 15". Go out any further, and they don't bend, they break
right of, and you end up with a similar scenario as above.

So it may be time to go back to the drawing board! You might think in
terms of Titanium, and then you begin talking real money, though with
the aircraft industry up there, you may have a cheaper source!

What you need is a material that can take the extended end loading, you
might think of a fiber glass or Kevlar pole, which could be extended
out beyond the side of vehicle, and supported in the middle folcrum on
the roof gutter independent from the existing rack. This pole could
extend across the top of the vehicle and be attached for loading to the
other end of the rack. Think in terms of a teeter-totter, with one end
held down, and the other end sticking out beyond the side of your car.
The right material can carry a significant load.

The right material could even be just a clear of knots, straight
grained piece of Douglas Fir. A hand selected 2x4, from the local
lumber yard. Trees are subject to end loading by the wind, and are
incredibly strong.

When you are done loading your boat, the system will not fold up all
nice on top like a commercial unit would, but you could pull it and
place inside vehicle, or lash along side the kayak on top.

Now your car begins to look like a kayakers car should look. Check out
the pictures on Wilko's website, and you will get a better idea of
where this is headed. :-)

My only other suggestion also, is that when you lift the front end up
on the extension, that you tie a loop of rope around it to act as a
safety to keep it from slipping off the extension as you lift the back
end. this would be especially important if it is windy, or you are
parked on a slope, which could result in the front end sliding off or
deciding to take a lesson in "flying like a kite!" and you are holding
on to the little end of the kite.

I am sort of like a bull, when it comes to loading stuff as you know
(:-), and I just lift my 70 lb boat onto the top of my Caravan. One
time the wind caught the boat as I had it overhead and did a windvane
number on my back. I am re-thinking my loading procedure even as I
write this all to you. It is amazing how you get smarter each time you
try to break something. TnT

"Tinkerntom" wrote in message
oups.com...
Hey Wilf, You never said that I can find, what sort of roof rack do you
have? Is it a Commercial unit? If so, most of them have some sort of
extender system already made. No point in reinventing the wheel.

The problem with electrical conduit is two fold. First it is steel and
would begin to get nasty fast when exposed to salt water. Secondly, it
is designed to bend, which is great in some projects, but you would not
want it to decide to bend when you have the kayak on it and lifting
other end. It would result in a loud crash, and possibly a broken boat
or twisted back as you try to keep the loud crash from happening. Any
of these scenarios being bad.

I think you will also find that the commercial extender systems do not
extend as far as you are thinking like up to 28". So, though they use
extruded, hardened Aluminum, which is amazingly strong, they only go
out like maybe 15". Go out any further, and they don't bend, they break
right of, and you end up with a similar scenario as above.

So it may be time to go back to the drawing board! You might think in
terms of Titanium, and then you begin talking real money, though with
the aircraft industry up there, you may have a cheaper source!

What you need is a material that can take the extended end loading, you
might think of a fiber glass or Kevlar pole, which could be extended
out beyond the side of vehicle, and supported in the middle folcrum on
the roof gutter independent from the existing rack. This pole could
extend across the top of the vehicle and be attached for loading to the
other end of the rack. Think in terms of a teeter-totter, with one end
held down, and the other end sticking out beyond the side of your car.
The right material can carry a significant load.

The right material could even be just a clear of knots, straight
grained piece of Douglas Fir. A hand selected 2x4, from the local
lumber yard. Trees are subject to end loading by the wind, and are
incredibly strong.

When you are done loading your boat, the system will not fold up all
nice on top like a commercial unit would, but you could pull it and
place inside vehicle, or lash along side the kayak on top.

Now your car begins to look like a kayakers car should look. Check out
the pictures on Wilko's website, and you will get a better idea of
where this is headed. :-)

My only other suggestion also, is that when you lift the front end up
on the extension, that you tie a loop of rope around it to act as a
safety to keep it from slipping off the extension as you lift the back
end. this would be especially important if it is windy, or you are
parked on a slope, which could result in the front end sliding off or
deciding to take a lesson in "flying like a kite!" and you are holding
on to the little end of the kite.

I am sort of like a bull, when it comes to loading stuff as you know
(:-), and I just lift my 70 lb boat onto the top of my Caravan. One
time the wind caught the boat as I had it overhead and did a windvane
number on my back. I am re-thinking my loading procedure even as I
write this all to you. It is amazing how you get smarter each time you
try to break something. TnT


How about seeing if you can get a section of Schedule 40 pipe about 3ft long
by 1 1/2 to 2 inches and attach it to the rack (no rust). Then get a good
length of hardwood dowel that fits inside. It could be very loose fitting if
you have 3 ft of it inside the pipe. I'm thinking 1 1/2 inch OD pipe should
work great with a 1 inch or 1 1/4 inch dowel - like you buy to hang the
cloths up in your closet. Toss the dowel inside the car when done (if the
paddles fit, so will it). A dowel this size with 3 ft of support should hold
for most boats. I would think it would hold 100 lbs distributed across the 2
ft or so you have sticking out. -- Stress test away from the car - I don't
want to get blamed for a paint job after it breaks ;

The beauty of using wood is you should hear it start to fail before it lets
go. Unlike the conduit which may just fold-up without a sound.

Ken

No Spam wrote:
"Tinkerntom" wrote in message
oups.com...
Hey Wilf, You never said that I can find, what sort of roof rack do
you
have? Is it a Commercial unit? If so, most of them have some sort
of
extender system already made. No point in reinventing the wheel.

The problem with electrical conduit is two fold. First it is steel
and
would begin to get nasty fast when exposed to salt water. Secondly,
it
is designed to bend, which is great in some projects, but you would
not
want it to decide to bend when you have the kayak on it and lifting
other end. It would result in a loud crash, and possibly a broken
boat
or twisted back as you try to keep the loud crash from happening.
Any
of these scenarios being bad.

I think you will also find that the commercial extender systems do
not
extend as far as you are thinking like up to 28". So, though they
use
extruded, hardened Aluminum, which is amazingly strong, they only
go
out like maybe 15". Go out any further, and they don't bend, they
break
right of, and you end up with a similar scenario as above.

So it may be time to go back to the drawing board! You might think
in
terms of Titanium, and then you begin talking real money, though
with
the aircraft industry up there, you may have a cheaper source!

What you need is a material that can take the extended end loading,
you
might think of a fiber glass or Kevlar pole, which could be
extended
out beyond the side of vehicle, and supported in the middle folcrum
on
the roof gutter independent from the existing rack. This pole could
extend across the top of the vehicle and be attached for loading to
the
other end of the rack. Think in terms of a teeter-totter, with one
end
held down, and the other end sticking out beyond the side of your
car.
The right material can carry a significant load.

The right material could even be just a clear of knots, straight
grained piece of Douglas Fir. A hand selected 2x4, from the local
lumber yard. Trees are subject to end loading by the wind, and are
incredibly strong.

When you are done loading your boat, the system will not fold up
all
nice on top like a commercial unit would, but you could pull it and
place inside vehicle, or lash along side the kayak on top.

Now your car begins to look like a kayakers car should look. Check
out
the pictures on Wilko's website, and you will get a better idea of
where this is headed. :-)

My only other suggestion also, is that when you lift the front end
up
on the extension, that you tie a loop of rope around it to act as a
safety to keep it from slipping off the extension as you lift the
back
end. this would be especially important if it is windy, or you are
parked on a slope, which could result in the front end sliding off
or
deciding to take a lesson in "flying like a kite!" and you are
holding
on to the little end of the kite.

I am sort of like a bull, when it comes to loading stuff as you
know
(:-), and I just lift my 70 lb boat onto the top of my Caravan. One
time the wind caught the boat as I had it overhead and did a
windvane
number on my back. I am re-thinking my loading procedure even as I
write this all to you. It is amazing how you get smarter each time
you
try to break something. TnT


How about seeing if you can get a section of Schedule 40 pipe about
3ft long
by 1 1/2 to 2 inches and attach it to the rack (no rust). Then get a
good
length of hardwood dowel that fits inside. It could be very loose
fitting if
you have 3 ft of it inside the pipe. I'm thinking 1 1/2 inch OD pipe
should
work great with a 1 inch or 1 1/4 inch dowel - like you buy to hang
the
cloths up in your closet. Toss the dowel inside the car when done (if
the
paddles fit, so will it). A dowel this size with 3 ft of support
should hold
for most boats. I would think it would hold 100 lbs distributed
across the 2
ft or so you have sticking out. -- Stress test away from the car - I
don't
want to get blamed for a paint job after it breaks ;

The beauty of using wood is you should hear it start to fail before
it lets
go. Unlike the conduit which may just fold-up without a sound.

Ken

Ken, the only thing I would question, is that where the dowel comes out
of the pipe, would represent a sheer line. All the load on the extended
dowel would be concentrated at the sheer line as a breaking force. You
would not be able to take advantage really of the flex of the dowel
inside the tube, to dissipate the energy as a flexing force, and it
would tend to break at that sheer line.

You are right on though about hearing the dowel break.

Another function of the safety line that I recommended, is that if the
extension collapses, the boat would not fall clear to the ground.
Considering the car paint though, it might be equally important to use
some cushions in strategic spots in case the boat fell. You could just
hang a long noodle on the side of the car to take the bang.

or like Cyli indicated, you just don't worry about the paint! TnT

"Tinkerntom" wrote in message
oups.com...
Snip

Ken, the only thing I would question, is that where the dowel comes out
of the pipe, would represent a sheer line. All the load on the extended
dowel would be concentrated at the sheer line as a breaking force. You
would not be able to take advantage really of the flex of the dowel
inside the tube, to dissipate the energy as a flexing force, and it
would tend to break at that sheer line.

You are right on though about hearing the dowel break.

Another function of the safety line that I recommended, is that if the
extension collapses, the boat would not fall clear to the ground.
Considering the car paint though, it might be equally important to use
some cushions in strategic spots in case the boat fell. You could just
hang a long noodle on the side of the car to take the bang.

or like Cyli indicated, you just don't worry about the paint! TnT


You are correct about the shear at the point of entry but I think a hardwood
dowel of this size will take this force without complaint. My uncle used to
hang an old wood extension ladder on dowel pegs and it took 2 people to lift
that thing down. The flex in the exposed dowel would take the force of the
jolt of rough handling of the boat though. I did some google searching but
cannot find the shear strength of a dowel but I would guess that a 1 inch
hardwood dowel would take at least 500 pounds of pure shear force before it
would break. I have a 1 1/2 inch dowel here and I just stood on the end of
it with the other end wedged under my work bench -- yep lifted the bench
right up - the dowel flexed a little but easily handled me 275 lbs out about
a foot from the support.

Ken

No Spam wrote:
"Tinkerntom" wrote in message
oups.com...
Snip

Ken, the only thing I would question, is that where the dowel comes
out
of the pipe, would represent a sheer line. All the load on the
extended
dowel would be concentrated at the sheer line as a breaking force.
You
would not be able to take advantage really of the flex of the dowel
inside the tube, to dissipate the energy as a flexing force, and it
would tend to break at that sheer line.

You are right on though about hearing the dowel break.

Another function of the safety line that I recommended, is that if
the
extension collapses, the boat would not fall clear to the ground.
Considering the car paint though, it might be equally important to
use
some cushions in strategic spots in case the boat fell. You could
just
hang a long noodle on the side of the car to take the bang.

or like Cyli indicated, you just don't worry about the paint!
TnT


You are correct about the shear at the point of entry but I think a
hardwood
dowel of this size will take this force without complaint. My uncle
used to
hang an old wood extension ladder on dowel pegs and it took 2 people
to lift
that thing down. The flex in the exposed dowel would take the force
of the
jolt of rough handling of the boat though. I did some google
searching but
cannot find the shear strength of a dowel but I would guess that a 1
inch
hardwood dowel would take at least 500 pounds of pure shear force
before it
would break. I have a 1 1/2 inch dowel here and I just stood on the
end of
it with the other end wedged under my work bench -- yep lifted the
bench
right up - the dowel flexed a little but easily handled me 275 lbs
out about
a foot from the support.

Ken

Ken, Wilf, is talking about extending the dowel out 28", see what
loading the dowel breaks under now. This will prevent Wilf from falling
off his workbench, and you seemed more inclined to do this sort of
stuff! I mean testing, not falling off your bench! TnT

On 15-Mar-2005, "Tinkerntom" wrote:

extruded, hardened Aluminum,
[...]
terms of Titanium,
[...]
might think of a fiber glass or Kevlar pole
[...]
grained piece of Douglas Fir.

Old wood hockey stick. Ash - just cut to length.

Mike

Cyli wrote:

On 14 Mar 2005 19:02:10 -0800, "BCITORGB"
wrote:

(snipped)

Hmmmm... now you've got me worried. Just to check, do you have
expertise re van doors? I don't, hence my worry. I wouldn't have
thought that approx 50 pounds at the mid-point of the door frame would
be too much for the door-to-frame connection to withstand. However, I
haven't a clue. Does anyone else out there have any opinions?

Cheers,
Wilf


Only a few damaged car doors. Not by boats, but by kids. The doors
did stay on as long as they were kept locked closed and tied to the
frames if necessary, but that mean exiting through the car window,
which could be undignified, especially in a skirt or dress.

To what kind of forces were these doors subjected?
I know that all the doors on our cars can easily take my full 170 lbs at
the very end of the door frame without any damage to the hinges or parts
and would be totally unconcerned about putting the bow of my double on
top of the door temporarily for loading. My roof rack bars extend out a
few inches so I use that extra space for holding the bow while I walk
back to the stern and pivot it up, but the door frame would seem to work
ok as well if protected from scratches by a towel

Look at what holds your doors on. In a car it's two hinges. Stress
compounded with leverage is probably not a good thing for hinges. Look
at how many square inches of hinge there are. Look at the door.

Yup, those are the things I looked at before putting my weight on the
door. The hinges and attachment points looked like they were made to
handle some serious torque.

"Peter" wrote in message
...

Snip

Yup, those are the things I looked at before putting my weight on the
door. The hinges and attachment points looked like they were made to
handle some serious torque.


Depends on the car. My 21 year old diesel Mercedes - yep! My friend's old
Nissan - Nope! I tore a door just like his off at the scene of an accident
to clear the way to remove the driver (no tools - just pulled up really hard
and then down and a kick or 2. It tore the sheet metal of the door. The
hinge was intact but unattached). You did make me go look at the wife's Jeep
Grand Cherokee. I think I would set a boat on that door, seems plenty strong
enough to hold 40-80 lbs extra.


Ken