The Medway Handyman wrote:
Harry wrote:
Repairing a fence for my daughter and I had to use Hilti bolts,
drilling into concrete. I've never used the things before and they
don't come with instructions.

What exactly do you mean by Hilti bolts? Do they look like these
http://www.toolstation.com/shop/Scre.../d90/sd/p22455


In my book a Hilti Bolt is synonymous with a Rawl bolt, i.e. a
traditional shield anchor.

http://www.hilti.co.uk/holuk/page/mo...&nodeId=-86796


http://www.rawl.com/index.php?option...19&Itemi d=25

I figured it's simple enough, drill the holes, remove the nuts, fit
the metal plate, replace the nuts on the protruding threads and tap
the bolts into the holes.

Not sure what you mean by 'metal plate'?

Whatever he's bolting down with the anchor, presumably.


Of four bolts, three failed with stripped threads and were absolute
swines to get back out. What's the secret? Don't whack them in too
hard? Whack them in really hard? Screw the nuts down tight before
tapping them home, leave the nuts on the ends of the threads? What?
Any clues folks, the damn things are expensive and I've four more to
do tomorrow as well as the three I lost today.

Not sure how OP managed to strip threads!

To the OP:

The technique for a shield anchor is firstly to drill the correct size
and depth of hole.

Next, get all the dust and crap out of the hole. Try not to blow into it
unless you have goggles on.

Next, make sure the "expanding" part of the anchor is loose, otherwise
the anchor won't go in the hole.

The anchor should slide easily into the hole. If it doesn't, undo the
nut sufficiently that it protects the threads on the end of the bolt and
then gently tap the anchor into the hole until the body of the anchor is
flush or slightly recessed. This is by way of a playful love-tap. If you
have to force it, then either the hole's too small or you didn't clean
the crap out.

Remove the nut and washer; offer up the plate (or whatever) to the
projecting stud; replace the washer and nut.

Tighten the nut by hand. The anchor should bite before the nut is too
difficult to tighten by hand. If the whole anchor rotates in the hole,
then you have to assist the anchor to get started. Using a pair of Mole
grips, pliers or somesuch to stop the bolt from rotating whilst you use
a spanner on the nut should get the action of the anchor started.

Once friction has got a start, you can tighten the nut with a spanner,
socket or (my favourite) a ratcheting ring.

Job's a goodun.