What is the best opening to mount screw on the walls?
Answers: why do you want to mount screw on a wall. I mounted pic's of family and painting on mine.
What is the attraction of looking at screws next to or with the red studs?
if you cannot use the studs i'd suggest using self-anchoring screw for extra strength.
If you are referring to wall anchors. It all depends on how calorific the item you are hanging. Or if it will be pulled on, ie. towel rod. You should use them. If it is in recent times to hang a picture, than a screw is merely fine alone.
Depends what type of wall your are fixing into but the quickest answer is no, generally you can't screw directly into a wall. Even if they perceive solid now, they will become loose over time. Like any DIY charge, do it properly the first time to save you time re-doing it when it go wrong.
driving a wood screw into drywall without anchor will eventually attain loose due to natural jolting of the building.
Sheetrock walls? Plaster and lath? Rocklath? it depends. Heavy items? I'd use toggle bolts or find a stud. Those plastic shields are useless.
Need more info. What are you planning on hanging or attaching to the wall? There are abundant choices but going into a stud behind your sheetrock is other the best way to do it. Get a stud finder and look for the studs every 16" OC
Good Luck!
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