removing front axle from rim

Hi all' im repaunting my rims back to black, I have the rear one done, but for the front, I cant figure out how to nremove the axle from the rim. Is there a trick to it or am I just dumb haha.

It should just slide out. If it is stuck you may want to check those bearings while you have the wheel off the bike and replace them if they're not dead smooth. Ed