The grinder was a little loose so installed an extra screw with two of these washers. See video below. Just scale in the Z-axis for a tighter fit if you'd like it, but I wouldn't risk it. These machines are designed without a screw at that location so they should work perfectly without. Use this at your own risk.
I only share this model here for people with no design abilities. If you know any basic 3D CAD, you can design this in 10 seconds.
The author marked this model as their own original creation.