Greetings.
I want to drill a couple of additional bolt-holes through a 100x100mm
concrete spur post, which is currently supporting my fence.
I've got an SDS drill, but I'm worried that the post may shatter (after
previous "experience" with house-bricks, leaving a nice series of exit
wounds on the other side of the wall).
Has anybody tried this?
Any tips?
Thanks in advance, Al.
(email address no longer connected)

I've drilled a hole in my concrete 4" square post.
I clamped a piece of wood against it to avoid an exit wound. and
switched off the hammer action on the drill.
The problem is, that theyr'e re-inforced with wire, and you may hit one
& i trusted to luck!!
not sure how to detect a wire in concrete.

Al, Cambridge, UK wrote:
Greetings.
I want to drill a couple of additional bolt-holes through a 100x100mm
concrete spur post, which is currently supporting my fence.
I've got an SDS drill, but I'm worried that the post may shatter (after
previous "experience" with house-bricks, leaving a nice series of exit
wounds on the other side of the wall).
Has anybody tried this?

Yes. Go gently, from each side, with a pilot drill, then
enlarge, also from each side. You need to be able to drill
straight, obviously! To assist this, a piece of batten
pressed up against the post is useful to line up the bit.

You should not get an exit crated when drilling through
walls - the outside should be propped to prevent this,
and pilot holes should be drilled carefully. OK, I
know... try telling *that* to the television aerial man.

Chris Bacon wrote:
Al, Cambridge, UK wrote:
I want to drill a couple of additional bolt-holes through a 100x100mm
concrete spur post, which is currently supporting my fence.
I've got an SDS drill

Actually, I might not use an SDS drill in this case, just an
"ordinary" hammer drill, using sharp bits.

coaster wrote:
I've drilled a hole in my concrete 4" square post.
I clamped a piece of wood against it to avoid an exit wound. and
switched off the hammer action on the drill.
The problem is, that theyr'e re-inforced with wire, and you may hit one
& i trusted to luck!!
not sure how to detect a wire in concrete.

It's put in at the corners, or the slot edges for slotted
posts, and held in place in the mould with plastic Xs. (the
wire goes through the middle of the X).

Thanks for your replies.
Al