Ummm?
You are asking if anyone has EVER custom painted a helmet?
Ever heard of Troy Lee Designs or looked inside a motocross magazine?
There dozens, if not hundreds of companies custom painting helmets. I think there is even a thread on here (maybe
www.ridemonkey.com) showing people's custom painted helmets.
I myself used to paint helmets (Twisted Mind Designs). I did about fifty of them. Painting motocross helmets in the early 90's was very popular because helmets either came with hidious graphs or none at all.
The real trick to painting helmets and having them turn out nice is to use a base coat / top coat system with a base coat that dries quickly and leaves a low surface edge. You can use painters masking tape and frisket to mask off the areas you don't want to paint.
Buy yourself a cheap "touch up" gun. These are paint guns, but smaller and shoot a smaller pattern. I bought expensive ones, but found that $20 (or $10 sometimes) worked just as good.
I used House of Kolors for wilder colors and PPG for regular colors and their acrylic urethane top coat. I was nowhere near the best helmet painter, but I had a lot of fun. Now a days you can buy a really nice helmet with a sweet paint job for less than it would cost me to paint one. I just wear a off-the-shelf D2 and SE2 now.
Here's some old photos of some of my helmets. Purple was really big in 1995.:thumbsup: