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Why would plastic anchors pull out of the wall?
I have drilled holes in my concrete wall (good hard concrete) with a regular 8 mm concrete drill. They all seem like good holes and I've taken care to remove all remaining dust from the holes by blowing inside with a straw. My 8 mm plugs also go in with just the right amount of friction.
But when I start mounting the cupboard and really want to tighten the last bit, instead of just getting more secure, the plug starts creeping out of the wall! I've tried a couple of different types of concrete plugs, but they all yield the same result.
Is it a good idea to take some kind of filler material and jam it in together with the plug before mounting?