drillhole
I drilled with 3/8" still bit as instructed, but the holes seem too large for the screws. I'm wondering what the best fix for this would be. Fill the holes up with wood glue and toothpicks and screw into that, or widen the holes to place anchors in and screw in there? Any suggestions would be appreciated.
No, this isn't normal. Your anchors don't fit to your screws. What is happening is that the tip of the screw reached the concrete, and, of course, you can't force a screw into concrete - not even with a drill or a electric screwdriver, and certainly not by hand.
This picture shows how anchor and screw should fit into the hole. The hole definitely needs to be longer than the screw. The screw should be a bit longer than the anchor, but not as long. Maybe the clerk saw that you have picked an wood screw and gave you anchors suited for the second situation. It doesn't hurt to use wood screws with anchors in a concrete wall, you'll just have the cap jutting out a bit. But the length of the screw should be only a bit longer than that of the anchor (the surplus should equal the length of the tip + the length of the attached thing), and your cap will stick out a bit if the thing you are attaching isn't soft enough for the cap to sink in.
The table shows how to determine the correct hole depth. It also tells you what diameter of anchor and drill to choose for a given screw. As for the length of the screw, it is determined by the weight it will have to carry. Vertical screws are more problematic than screws in walls, because gravity is pulling in the direction of the hole, not at 90° to it. Light curtains will be OK with your size screw, but don't put any molton on them.
This is very complicated, and I'm hoping that you'll stick through all of the steps with me. ;)
(No, really, that's the answer. You can't patch the drywall and put anchors in; the most you could hope for would be re-drilling holes near to your anchor, but you really risk cracking the drywall if you do that. I'd just get bigger anchors.)
Best Answer
Putting screws directly into drywall, particularly the type shown in your photo, will rarely (if ever) work. The drywall is not strong or firm enough to hold screws without hollow-wall anchors of some sort.
You need to tell us more, however; if you want advice as to what sort of anchoring system you need. What is the reason you need to put screws in the wall?