Retaining Nut for 1/4x20 bolt with Dragon Pattern

Somehow when I spent a year replacing the motor in my fan, I lost the little retaining nut that kept the grill on. So I printed one. Rather than be plain, I mashed a Dragon onto it.
Light fixtures

I also added a nut pattern that might work with those nipples from a light fixture, but I haven't had a chance to try it. The threads library I'm using isn't really designed for the 1/8" I.P. thread.
Update

I made the thread go a little more into the retaining part so it could screw on more completely