I am picking up a canoe in a few days and will be traveling about 300 miles with it on the interstates.
Unfortunately my secure Yakima roof rack, and all my straps are not with me. I was able to scrounge some of those el cheapo foam blocks that go under the gunnels and some straps and I bought some rope.
I am planning on putting one strap over the belly of the canoe and then through the car, and two tie downs on the front and the rear, and then keeping my fingers crossed.
I am used to secure systems where I know the boat or boats will never leave the roof and don’t like this at all.
Has any one had instances where car topping like this the blocks and canoe slid around the roof?
Any other tid bits that might help short of throwing a big fish net over the whole works?
Jack L
Oh sure I have experience with slide
around. I don’t think you want help with that.
It works better if you can bring those straps closer to the hull… ie are there any side bars on the car?
Two additional possibilities
As you already know, you'll have quite a bit of potential for side-to-side movement, even if your front and rear tie-downs form a "V". The movement will be limited enough that the boat can't come off the roof, but the movement possibility will be considerable.
First Idea:
Since you are already proposing putting one or more straps through the passenger compartment, here's more you can do. Loop a strap or rope over the top of the canoe and back underneath to the SAME side. Maybe you can anchor that to a door pillar or something. Do the same on the other side, and the boat will be trapped between those two loops, unable to move left or right. Unfortunately, it will still be able to pivot around that securely-anchored point, so if you could do this at two locations, one toward the front and one toward the rear, you'd have it made (I often do this with my roof rack as a very good substitute for gunwale blocks). The only convenient way to make this happen ("convenient" in terms of making use of what's there, not so convenient in terms of getting in and out of the car!) is to loop one set around the top frame of each front door, and another at each rear door. Maybe a good compromise would be to use the top frame of each rear door for one pair of these straps, and the door pillars for the other set. That way the front doors are still operable. Or maybe a strap wrapped tightly through the passenger compartment would be a reasonably secure anchor point, maybe using a Prusik-type of attachment to the loops that go around the boat from each side.
Edit. Kim's post reminds me of something. If you have a factory rack, you can use it as your attachment points for these pairs of opposing loops. If you can do that, you'll be in fine shape, and will have no need for anchoring to door frames or pillars.
Idea #2:
Your front and rear tie-downs will be much more effective if they oppose each other, but with the normal way, they don't. The normal way is to make the rear tie-downs attach to the rear stem of the boat. With that setup, any movement of the boat which tends to loosen the front tie-downs will also loosen the rear ones. Instead of doing it the normal way, make the rear tie-downs go forward to a thwart. With that arrangement, you can tighten the front and rear tie-downs so that the boat gets "stretched" between them, and that does a much better job of limiting side-to-side movement, as well as insuring the boat can't leave your roof, than can ever be possible if the rear tie-downs attach to the rear stem (the only time that attaching rear-tie-downs to the rear stem makes sense is on a really small car, where the front of the boat sticks out ahead of the front end of the car. In THAT case, and no other, attaching the rear tie-downs to the rear stem of the boat causes the front and rear lines to work in opposition the way they should).
As usual GBG illustrates better than I
That rear tiedown ideally should go straight down to some attachment points at each side of the trunk or hatch. Same for the front of the boats. The one warning is you don’t want front tie downs to interfere with your wipers or be right in front of your eyes. This all depends on your car/ boat combo but the straighter down the bowlines can go the better off you will be.
Erics post made me reminisce about front door vent windows… sorely missed and were so useful. They could have been looping points.
In this particular case, Kim, …
… it would be better if the front and rear tie-downs do have some slope to them, with the direction of slope being opposite for front and rear. That way you can get that “stretch the boat” action happening between them, which becomes more important when you don’t have a “real” roof rack to hold things still. Otherwise, with a real roof rack, I’d be happy enough if the end tie-downs went straight down from boat to car.
A long time ago
Back in '85 I had to transport a 17 foot aluminum canoe on top of my '82 Saab about 200 miles with foam blocks. Fortunately I had two long straps so was able to run straps over the canoe and through both the front a rear doors, and used “V” tie downs from the bow an stern to the real bumper supports. I still had some side to side slippage.
However I did choose not to take the interstates and stayed on the two lane roads. Max speed was 55. I also stopped about three times just to tighten things down. It was a nice day and made for a pleasant leisurely drive through the Iowa countryside. I also stopped at an ice cream shop for each strap check 
Go to a mattress store, buy a bed set,
and tie it over the canoe with hairy brown twine. This seems to be the accepted approach for roof transit without racks.
In fact, you may not need to buy a bed set. There are usually some along the interstate, free.
Seriously, though, once I had to transport our OT Tripper on my mother-in-law’s Mercury Sable, and I took the same approach as you… foam gunwale blocks, straps through the car, and lots of triangulation. Fore and aft triangulation, and the ends of the canoe tied with separate ropes, not one rope passing through the grab handles. By careful triangulation I was able to keep the canoe firmly in place at normal highway speed.
Here’s what you do
First of all, wrap the boat with strong rope, over the top of the boat and under the roof of the car (i.e., go through the passenger compartment. Tie a loop in one end of the rope (bowline works well) so you have a good pulley point for tying it good and tight.
Do it again as far away from the first wrap as possible.
Now do it again, except this time you tie the rope around a thwart, pass it through the car, and tie it to the other end of the thwart. But before you tie it off, tie a figure-8 knot in the rope so that it butts against the inside of the car. Tie another figure-8 knot to butt against the other side of the car. Then tie it off to the other end of the thwart.
Tie the other thwart the same way, if possible. This arrangement will keep the boat from slipping sideways, provided you have good bow and stern tie-downs as described above.
Unfortunately, none
Jack L
I was thinking about number 1, but …
carrying it a step farther, and after looping it back under the same way, go through the car and then repeat it on the opposite side.
Jack l
That might work too
The trick will be finding a way to make sure this continuous loop of rope doesn't slide through the passenger compartment too easily. It will only be the rope's friction with the door gaskets and edges of the roof that keep that from happening. Strategically placed knots that can't slip through the door joints would help. I bet you could do that with smaller ropes attached with a Prusik. Put each Prusik either just inside or just outside each door joint, and run a smaller rope through the joint to another solid anchor point, such as the opposite Prusik. The easiest way would be to put each Prusik just outside the door joint and run the smaller connecting rope through the passenger compartment alongside the rope being secured via them. The Prusiks would be easy to adjust right up to the door joint, unlike a knot in the rope that has to be positioned by trial and error. Either the Prusik, or the knot attaching the secondary rope to the Prusik, would serve as the "stopper" to keep the main rope from sliding through the door joint.
I'm sure I spelled "Prusik" wrong, but I'm also pretty sure you know what knot the mispelled word refers to.
Homemade soft rack
Here is what I did for a soft rack that I still use from time to time on cars that don’t have a rack. It requires two sections of PVC pipe about 4 feet long, two pool noodles, and two ropes or straps about 12’ each. Cut the PVC to be about 2” shorter than the roof. Cut the pool noodle to fit the PVC and slide over the pipe. Run the rope or straps trough the PVC and strap through the open doors to hold on roof. This gives you two padded cross bars that spread the load over a greater area of the roof. I then slide rope or strap between the roof and the noodle covered PVC pipe to strap the canoe down. I also use a V type front and back tie downs to keep the canoe from rocking back and fourth or wagging side to side. I have less than $25 in the rig and that includes the $12 for the two straps.
Email me and I can send you a photo if you need it. I have traveled to the Everglades from SC doing interstate speeds with no trouble or sliding on the roof with a 16’ canoe. I also have a soft rack like this that I put those grey minicell foam kayak saddles on, and have carried 2 17’ sea kayaks on the roof to the cost on interstate 26. Hit a deer with a kayak on top this rack and the kayak stayed put, but my fender and headlight took a beating. The one problem with this system is a hard rain will soak the ropes or straps that run trough the inside of the car and drip water inside. And remember the V front and back tie downs are required to make it stable.
use shelf liner under the blocks
http://www.homedepot.com/s/shelf%2520lining?NCNI-5
in case the link does not work - go to home depot and buy spme "shelf liner" or whatever they call it - a soft, grippy rubbery material that looks like it is woven.
from experience, I guarantee you that it will significantly help to keep those foam blocks from sliding around. the blocks themselvs are not that "sticky" to the roof
otherwise, as mentioned above, trying to tie the boat so that it can't shift from side to side, rather than just a strap over the hull helps a lot - either tie from thwart end, thru the car interior and back to the other side of the same thwart, or around the hull and back to the same side - I rigged up some flat metal hooks, like the door clips on yakima towers, (covered with shrink tubing) that I used to help keep the boat from sliding around - those semis really push a lot of wind when they pass you in either direction - just the foam blocks alone has never worked to keep the boat from sliding sideways in the wind
All good tips
but let me add this, when you loop the ropes over the hull start from under the canoe and then loop the ropes over and then through the car. This will make a noose of sorts that will help keep the canoe from sliding sideways. I tried just going over the hull with my kayak and it tipped up on its side and almost came off the car, and I had it on my Yakima rack. I tried the under/over looping and problem solved.
The sliding problem…
... has been addressed by similar methods, but this is a good idea too. Knotting or twisting the rope at the top crossover point would make this method even better, as that would eliminate the potential for the rope to slip around the hull and still let it wander. Also, it's worth clarifying that the crossover point IS on top, because the first few times I read your post I envisioned running the rope under, over the top, and under again to reach the other side, which would put the crossover point underneath, and that wouldn't keep the edges from lifting or the whole boat rolling while tied down.
There still remains the problem of the rope possibly slipping within the passenger compartment, but I think the Prusik method I described would work, for this and each of the other proposed solutions where such slippage through the door frames could occur.
I'm sure Jack is gonna get that canoe home in fine style.
Got home a few hours ago with my…
new baby, and for the 250 plus miles at mostly 65 MPH it never budged an inch in any direction.
I did like I described above using four straps over the canoe. Luckily my new Suburu has a grab handle above all four doors, so I secured one strap to each of the handles, and then with my superb bow paddlers (Nanci's) skill with the taut line hitch for the two front and two rear rope tie downs.
I started out at 40MPh, increased to 50, then 60, etc.
the only problem was the horrendous wind noise.
Some thing nice on this new, and my first Suburu: When I picked the boat up, I was getting 32.1 MPG and when I got home after the 250 miles over lots of mountains and the high speed driving I am still getting 32.1MPG
Needless to say; in the future when the bow paddler says "leave the rack on the car" I will adhere to her command!
I still don't trust those blocks
Jack L
Great!
I wonder if anyone has used those overhead handles in such an industrious way before. That sure solved the main problem some of us were contemplating, in a very easy way!
maybe now you can sell all those yakima
fittings. Ya don’t need them!
No way !
All my Yakima and Thule mix and match stuff are one with the vehicle when they are installed, and there is never a worry about any boat coming off as long as the roof stays on.
Very seldom need that front and rear nonsense except when I want to protect the bow of an 18’-6", 19 pound carbon fiber knife point hull from breaking off when a big rig comes by.
Jack L
I’m just giving you grief
Last time I cartopped with nothing but foam blocks on the gunnels it terrified me.