just finished this front rack which will accompany the hand made waxed canvas bag made by Anhaica Bag Works.
i have also been toying around with a new idea for a decaleur(a traditional french method of attaching a front bag to a rack)
typically decaleurs hold the front bag very securely and make it easy to remove the front bag, but every once in a while, you hit a bump just right and your load is distributed just so and the bag jumps off of the mount. one way to prevent this is to also have a strap which holds the bag to the rack, this is not the most elegant setup and requires more work to remove your bag.
my new design utilizes two spring loaded rods attached to the mount on the bag and by pulling both pins outward the bag comes off quickly and easily.
check out the photos.