Dave Plowman wrote:

Then you're using the wrong wall plugs, or wrong sized drill.

I'm mounting some (very) heavy duty TV wall brackets. The screws and plugs
came with the brackets, as did the drilling/fixing instructions.

The wallplugs were those awful flimsy grey things, mostly hollow and with
little sticky-out prongs. Internal walls are breeze (clinker) block with
cement render.

My initial instinct (which I should have followed) was to bin the grey
wallplugs and use the superior brown Unifix plugs. However, I decided to
use the supplied plugs and screws. The holes were drilled exactly as
instructed and the screws where tightened........... well that's the
problem, they never actually achieved tight.

Certainly, if I had drilled a hole smaller than was specified and hammered
the plugs home, then the screws would have gripped better.

Much better however, would be to use a system I know works well: Unifix
plastic wallplugs and traditional woodscrews.
--
Mike
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