Carrying stuff on your back while riding can be a pain and some people will go to great lengths to avoid sweaty back syndrome. I have seen creative uses for buckets before, but this might take the cake. Reader Mike, who also submitted a DIY Bike Flasher, transformed a 5-gallon bucket into a cool trunk.
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I hate to wear anything on my back while riding, but I like to bring a backpack to work to carry my Doritos and whatnot. I'd been sticking the backpack to my rack using a four-legged spider of bungee cords, which added a few minutes of fiddling to my day that I wanted to subtract.
I'm using a horizontal 5-gallon bucket with a hinged plywood lid. The little curved white bits between the bucket and the plywood base are plastic cutting board material, but plywood would work just as well (maybe better). This design has good balance (maybe better than a pannier on one side might be? I've never used one of those so I'm ignorant there) and is water-resistant (though I haven't ridden in the rain yet). But the main advantage I wanted was a super-fast load/unload, and I definitely got that!
5-gallon bucket (don't buy one - find one, they're all over the place!)
plywood (base is about 12"x8", lid is a 12" circle)
hinge (one is okay, two would be better)
jigsaw, driver/drill, wrench.
A few notes on construction: The plywood parts are all stuck together with wood screws, and the bucket is screwed to the curved plywood pieces using wood screws with washers. J-bolts hold the base to the bike rack. A pin holds the latch shut. The thickness of the plywood shouldn't make too much difference, but I used 3/4" for the base parts and the stationary part of the lid, and 1/2" for the part of the lid that swings. Cost: the price of the bucket is probably the biggest variable, but can often be $0 if you're willing to do a little poking around - I know it's hard to believe but folks throw these away! The hardware should be under $6. Time: about an hour.
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