My lathe chuck key broke!

[ARC-170]

Thanks everyone! I've never dropped it or hammered on it, so it must be an old flaw. I went to file it and the file just skated across it. I ended up using my disk sander and a rose index to keep it square. It fits a tad tighter now as well.

 

[CJ5Dave]

I have an old chuck with a 9/16 square hole. Did not come with wrench. Make one was the only out.

 

[CJ5Dave]

Here are a couple you can have if the repair does not work out. One is 0.25, one is 0.28. One is homemade. I bought a box of keys off a woodworking forum, none fit my chuck of course.