On ANY small car like the one pictured there is no substitute for hood straps. The problem is that on rough roads it is too easy for the ropes or straps to entire the wheel well leading potentially to the same disastrous consequences.
To try and remove the crease in the polypropylene try heat.
If you don’t want to pay the Thule price, or just don’t want to wait, it’s really easy to make hood loops.
Go to your local hardware (or outdoor) store and buy a foot or two of 1" nylon webbing strap (cheap, maybe $1.40/ft.). Open your hood and look for two “friendly” bolts holding the fender or radiator support bodywork, i.e. where you want the tie-downs to be, unbolt one, and use it to size the hole you’re going to make in the web strapping. Cut the strapping into two lengths that, doubled over, will give you what you need to stick out from under the hood. Fold the material over to make the loop, and using a lighter, burn a hole through the two matched-up ends. (Be wary, don’t let the nylon melt too fast, or you’ll be starting over!). Try the bolt to see if it will screw through the hole; if too small, re-melt just a bit to make it fit. Once you’ve made your strap, just run the bolt through the holes and ratchet it back into place; bodywork bolts almost always have an integrated washer on them, so it will tighten down just great. When not in use, fold it over to hide from the sun under the hood. I did this to my Cherokee, and it is sooo much easier to rig than the previous chore of threading the rope through the foglight openings and trying to keep everything snug while tying down. Also, it seems to hold the kayak much more securely.
And yes, use ropes. I have a carbiner latched to the kayak’s carry-handle, and run the rope to it, secured with a double slide-knot; takes me about 60 seconds to secure the front of the boat now.
I was wondering about the effectiveness of running longer pieces of (e…g.) 1"x1" spruce (feathering on ends if necessary) along a dent, wedging in cross braces athwart and/or vertically as needed and leaving out on a hot day
One would need to adjust bracing pressure by wedging braces in more snugly or using a couple of small bottle jacks while trying to ensure original cross-section integrity I expect.
Probably good idea to align boat long-axis N-S to achieve as symmetrical a solar heating as possible).
Anybody here have any experience with attempting anything like this, successfully or otherwise?.
Looks from here like you did a good recovery as is though
I have done this before when I bent my whitewater kayak around a rock in the river. You can smooth the dent out of the side of your kayak with a heat gun and a spray bottle of cold water. Put the heat on it and use a heavy, clean glove to apply pressure. Use the spray bottle to firm things up when the plastic gets too hot and mushy. You can probably also find videos on Youtube of plastic kayak repair.
