Fixing loose front and Focus problem on SIGMA 24-70mm D 1:2.8 EX

This lens has a focus ring that could not go all the way from near to infinity, because there was 3 loose screw's in the front helicoil, that block's the focus ring, but it was "easy" to fix... Now it works pertect... :-) Use a rubber tool for taking off the nameplate, then unscrew the 3 screw that hold's the front plastic ring..., NOT the 3 screw's for the adjusting of the front lens group. NEXT: there are 3 loose screw's at the side of the helicoid that will come loose by time, just use a SMALL drop of BLUE screw fastner that are LOCTITE 243, ... that's it. UPDATE: It's better to use the LOCTITE 222 threadlocker.. Cheers :-)