You can make some tie downs with rope and a decent knowledge of knots.

You can take a 18" length 3/8" line an put bowline's on each end. Then loop it over the rack and put the bungee in both loops.

Or you can make something more permanent using a hitch to secure it to the rail and put a bowline on the free end.

Ashley's Book of knot's has a variation of the Clove hitch where the end is tucked under the first loop outside the crossed section, but I can't remember the name. It's definately not the constrictor knot, but is similar. The constrictor's final tuck goes under the first loop AND the crossing section. The Clove hitch won't nip well enough unless you use coarse line.

I'll look the name up tonight if you are interested.


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Gary