Drilling paving slabs - Need to drill 1/2" holes in slabs....

[Dave_L]

Recently laid 9m2 paved area in the local playing field in readiness for a wooden picnic table. As the table is in a public area, it needs to be bolted down with suitable security bolts, which I have got.

Having never drilled 35mm slabs before - plus I don't want to damage/crack any - can anybody give me any ideas as to the best way/method etc of drilling these four holes?

[lutonlagerlout]

use a battery drill with a hammer option dave,i find that although these are less powerful they tend to do less damage
i use a 18 v bosch with a 7 mm bit then screw a 7.5 mm masonry fixing in(no plug) our hilti 110 drill just seems to crack them every time
either that or use a 240 drill without the hammer on and try and just drill through with no hammer (new drill bit req'd though)
cheers tonyLLL

[bobhughes]

I would drill a pilot hole first - say 5mm - then work up to the size needed. Also drill the slab out to a clearance hole so the bolts are just anchored in the bedding.

[Dave_L]

Thanks guys - time to get the 18v Dewalt and a selection of masonry bits out then