I have been using these bags on my bike for around 15 years. I basically copied the design from commercial panniers back when I couldn't afford to buy one. I take a canvas bag, about the size of a grocery bag, and bolt a piece of plywood inside of it. The two top bolts connect to hooks that hook onto a rear-mounted bike rack.

It makes for a nice, big saddle bag that holds lots of stuff and it's also convenient to carry by the handles when you leave your bike.

Every few years the canvass bag wears out and I replace it. These bags were very common ten or fifteen years ago, but I don't see many these days. Some vendors have sturdy nylon bags that might work as well The photos in this instructable were taken as I did my latest refurbishment.

Step 1: Tools and Materials

Wood Saw
Metal File
Electric Drill
Crescent wrench and/or box wrenches

large canvas bag (or any other suitable fabric)
1/4-inch plywood approx 12 x 14 inches (size depends on your bag)
Large Canvass or Nylon Shopping Bag
24 inch long bungee cord
2 1¼ steel right angle brackets with two screw holes on each leg of the bracket
2 ¼-20 threaded steel hooks
6 ¼-20 x ¾" long bolts
6 ¼-20 nylon lock nuts
4 ordinary ¼-20 nuts
10 ¼-inch washers
2 ¼-inch lock washers

Smart idea! <br> <br>I wonder if a square aluminum frame would work instead of plywood?
Thanks a lot for the instructions. I recently got a rear rack and definitely want to make these for grocery shopping, it's awkward to try to strap a bunch of things on top of the rack. <br> <br>I think this could be made lighter by using a piece of plastic board instead of plywood (like from an old signboard or those things that people use for standing up poster presentations).
You're welcome! <br> <br>Yes, plastic could work, but keep in mind that the board will take a fair amount of abuse if you use the bag a lot, so not all plastics will be durable enough. My piece of plywood finally wore out after about ten years of use (screw hole broke in a lower corner).
In the UK and Europe, you get bags similar to this made from Jute (or hessian) very cheaply in supermarkets. Great conversion!<br><br>
(I <3 KQED!)

About This Instructable




Bio: By day I'm a mechanical engineer at a university laboratory. In my free time, I do my own projects.
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