Not with manual way, is there any addon or perfect way that can make a M6 screw? Must be able to fit a 6x12 sign in landscape that will have two holes at the center point 0.30”/7.62 mm from the top and bottom with M6 screws. Any suggestion or help how it works.
There's an add-on that's included but not enabled called Bolt Factory that has an M6 preset:
The problem is that its scale is off, but if you scale the screw by 1 / 1000 you'll get the correct scale.
You can try BoltFactory add-on. It's native, you just have to enable it at Edit -> Preferences -> Add-ons -> Add Mesh: BoltFactory:
Once enabled, you can go to Add ⇧ Shift + A -> Mesh -> Bolt:
A window will pop on the left where you can customise the settings to create pretty much any kind of Bolt / Screw / Nut you want: