Concrete setting

[Pete Verdon]

Last week my lodger had his motorbike nicked from our front drive. Fortunately it's now been recovered (tracking device) but he's obviously keen to secure it more firmly now. We've just spend the morning creating a hardpoint in the drive to bolt a new attachment plate to.

We dug a hole about 500x500mm, and 300mm deep, and filled it with B & Q idiot-grade ready-mix concrete (neither of us have done much of this sort of thing before). The steel plate is to be bolted onto this with expanding bolts.

How long does the panel think it might be before:

1. It's OK to roll the bike over the concrete so that it can be parked in its normal spot

and

1. we can drill the concrete and fix the bolts?

I've assumed that 1. will be ok by tomorrow, but maybe 2. will be a few days?

Any further suggestions for motorbike theft protection considered, too :-)

Cheers,

Pete

[Dave Baker]

"Pete Verdon" wrote in message news: [e-mail]...

I'm sure it will be a big help having the bike bolted to that but I wouldn't exactly call it bulletproof. That's about 350lbs of concrete, so not even as heavy as the bike, which a couple of blokes will lift out of the earth fairly easily. I'd have been tempted to drive a steel fence post or two into the bottom of the hole to a depth of a further couple of feet and then lay the concrete around those. Maybe even have a couple of bolts sticking out of the posts for the concrete to set round. That would anchor everything pretty immoveably.

[Pete Verdon]

Neither would I. But the only way to be certain that the bike won't be stolen from the drive is not to have it there in the first place. At this point I would expect the lock or chain to be the weak link rather than the concrete. The bike will be directly on top of the block, and it's between a pair of parked cars, so it's not going to be easy to work on.

He did look at something like this:

but didn't want to pay quite that much, plus we don't really have the space.

Pete

[Bill]

In message , Pete Verdon writes

[Steve Walker]

Indeed - if you drive a few lengths of scrap iron downwards/outwards (like roots) and then cover them with the concrete it's practically impossible to remove without breaking up a large area.

Hindsight advice is rarely helpful, but while we're here I'll suggest that it would also have been better to cast the fixing point in the new patch of concrete, rather than drill it (which will loosen it, and maybe even crack it). A short length of heavy chain or a closed loop of steel cable, for example.

[Pete Verdon]

Yup, we thought of that just as we were finishing off :-)

On the other hand, we would have needed more than just some random bit of scrap steel - that would have been too easy to cut with a hacksaw or bolt-cutters.

Pete

Pete

[Pete Verdon]

Heh. Unfortunately our drive is a bit too cramped to mark off an area as a minefield :-)

Pete

[The Natural Philosopher]

what's to stop people unscrewing the bolts?

I'd have cast some stainless U-bolts into the concrete

[Andy Burns]

Indeed, a chap down the road had a large bike, with a large chain through a large anchor on the garage floor, and nobody heard a peep the night it was nicked.

[Steve Walker]

What bolts?

Yeah, that would be good with big washers or a bit of scrap steel to resist pullout.

[Pete Verdon]

OK, let's agree that it's not perfect, but still an improvement over a bike chained to nothing at all.

Can anyone actually answer the questions about the concrete?

Pete

[meow2222]

Give it 2 days and you can do what you want. Until then its going to be very soft.

NT

[Steve Walker]

Yup. If you want to avoid stressing it, use resin to fix the anchor instead of expansion bolts.

[Mogga]

Tell him to paint it pink.

Get some CCTV.