I have used the button magnet closers on frame packs / handle bar bags. They hold well and add a nice classy touch. And then never get 'stuck'...
Here is a customization I did of an Army surplus ammo bag for a handle bar application. The magnet buttons just require a hole punched through the fabric, then the backing piece fastened. I usually then just glue a decorative button on the outside to match the style of the bag. These are pictured as the bare tabs without a button on top, you can see the construction better that way.
The mounting kit is a Topeak kit that is available on-line. I think this whole project cost me around $20-25 for surplus bag, mounting kit, and magnet closers.
Inside the upper flap I was able to slide a piece of stiff vinyl to help shape the back, and give the mounting bracket more support.
Sweet. Thanks. Another friend that was gonna help with it suggested snaps. But then I already sewed the zipper. Ugh. I was thinking about it and I think one end of over flap should have sorta a loose gusset, maybe with elastic to help pull it back down. That way it will stretch up and open nicely. Maybe. This is seriously my first sewing project beyond repairing some torn seams or putting a patch on, so I don’t know all the tricks.
Ok so keep this thread going, up to date... I was finally putting this together, after waiting on shipping for the seat tube reamer (which was a helluva procedure by the way, even with cutting oil and doing tiny bit at a time I had to make several passes and was straight tiring me out) anyway was putting together and thought the stem looked a little out of place. Too sharp and boxy.
So I had to mask up and run the flappy disc over it all for a minute. Think it matches better now.
But then I finally got my tires, and just started drooling looking at it coming together.
(Since I de-logo-ized everything else I was considering ways to sand off and maybe paint whitewalls or something, but hey, they really don’t look bad and I think I did enough. Also they won’t be around as long as the other parts)
Then finally, the first ride. Late at night, feeling sleepy, wearing flip flops, ripped around the yard for like 20 minutes. It feels great. This things gonna rock. Have some more tie bits and extras to finish up but it’s a bike now.