Wiktionary
axe to grind
n. (alternative form of ax to grind English)
Usage examples of "axe to grind".
When I had no axe to grind, I was Rod Arlin, a nice guy, a transfer, a credit to the house.
He says the valiant-red-army, trying to fight the capitalist-imperialist-warmongers (these are just names to him, Jonnie sir, he doesn't have a political axe to grind) had their attention on each other and didn't cooperate when an invader landed, and he says while tribal wars will and do happen, international wars among whole peoples are against the good welfare of the people.
And I should add I've got no axe to grind with movie people or with you or your friend.