Threaded depth adjuster tightened using a nut.

[woodhog]

My bullnose plane depth adjuster machine screw was a little wiggly.
After adding thread lock I made sure the depth adjuster machine screw was fully seated and tightened into the plane body.
I had to reduce the outer nut size by filing the flats so it cleared the plane iron.
The nut was placed onto the depth adjuster machine screw and gently tightened.
No more side wiggle I doubt it will come unscrewed any time soon.

[rwbuild]

Nice bit of lateral thinking