U-lock mount

My old bike had a U-lock mount on it that eventually broke. Since then I've thrown the lock in the pannier, which works, but is inconvenient since you have to dig it out whenever you lock up the bike. This is particularly annoying when it's raining.

Old bike

My new bike has a rack and a basket on one side. I modeled and printed a simple 2-piece mount to clip into my bike basket. 

Clips nearly finished on the printer. 

On hard bumps, the clips could get knocked off and my lock would go flying. I added two bolts to positively secure it and haven't had any issues since. This setup works really well and I expect it to be more reliable than the old mount and, if not, I can print replacements.