Sneezy thoughtfully wrote:

"Christian McArdle" wrote in
.net:

1. why does a screw sometimes keep on turning?

Because the hole is too big (either the drill wobbled, or you are in
soft mortar that fell out). If the problem is slight, just shove wrap
some toilet paper round the rawl plug, or shove some PVA down there to
glue the rawlplug in place so it doesn't spin.

If the fixing is expected to take a lot of load, redrill in a
different location so you get brick/blockwork, rather than mortar.


Had a similar problem with a cupboard - four screws in each corner to hold
it up. Two bottom ones went in fine but the top left one started spinning.
Took the cupboard down, banged in a chunky plug (couldn't see the original
plug - assuming there was one), and put the cupboard back up. Then the
bottom left screw started spinning... I think the cupboard was on and off
the wall about half a dozen times. Something very wrong with the wall - the
plaster seemed to be very deep and crumbly. It's up but I dunno for how
long Not my cupboard though - I was helping a mate. The funny thing is
that the only reason we took the cupboard down was to make the job of
wallpapering easier... Would have been quicker to paper round it

lol

I'm not sure I want to empty the bookcase and remove it again. I'm going to
try the following:

remove the screw
stuff matches down through the hole and into the plug
rescrew

see if that does the trick.

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