Post Hole Borer - landscaping question.

[Steve Lowe]

I'm doing a bit of hard landscaping in the back garden putting in some Marshall's woodstone posts and sleepers. the posts are 150x150mm x

600m long and need 200mm of their depth concreting in.

The Marshalls catalogue says they need to be a concrete base of

300x300mm x 200mm deep.

So far I've done 4 posts - dug 250mm deep - put 50mm of 10mm gravel in the bottom of the hole to level them up and they look pretty good.

I've got 20 more posts to go but hate digging - the hire shop has a petrol post hole borer but max dia is 250mm which won't leave as much concrete around the post as a 300x300mm square hole.

My plan now would be to bore a deeper hole - say 600mm - fill up the bottom 400mm of the hole with concrete to a depth of 400mm and some rebar that's say 550mm long - then when that's gone off - (time isn't important) pop the posts in and concrete up to ground level.

I'm kind of thinking that the extra depth of concrete should make up for the smaller cross section.

Any major reasons not to do it this way ?

Regards

Steve.

- Steve Lowe

- E-Mail : [e-mail]

- Before Replying Remove .NO.SPAM

- UK Resident although my e-mail address is usa.net

[Phil]

Yes - if your posts are 150mm then a 250mm hole only leaves 50mm thicknes around the post on the flats and 19mm on the corners!!!!

[Phil]

OTOH boring out then squaring off with a sharp spade to 300x300 would still be a lot easier than digging it all out by hand.

[Alan]

I've hired one of these from HSS in the past and found that you get a cone (ish) shaped hole as the spoil and disturbance at the top makes the hole a fair bit bigger than the cutter.

Get a two-man one, as even that was hard to hang onto every time it hit a flint, I'd imagine a single-man version would be near impossible.

As Phil says, it's easy to square up a round hole with a spade afterwards, so I'd just bore to the depth you need and concrete in one go. I've had good results with the dry "post-mix" stuff that you pour water over once in the hole.

Alan.

[Steve Lowe]

Hi

Mulling it over I'd come to the same conclusion, also as Alan says the hole might be bigger at the top anyway

- it might be handy for opening very large wine bottles as well !!!

Cheers

Steve.

- Steve Lowe

- E-Mail : [e-mail]

- Before Replying Remove .NO.SPAM

- UK Resident although my e-mail address is usa.net

[Bob Mannix]

[Bob Mannix]

Single man ones are actually better as there's a huge lever to help (you are at the business end but there's an engine and wheels some way away that resists being flung round). Two man ones have no built in mechanical advantage to hang on to, so tend to fling you about. I used a single man one quite successfully and got cyclindrical holes -100mm only though.

[Dave Liquorice]

Care to look at you units? A 600 metre post (some post!) with only 200 milli metres in the ground? The only thing I'm moderately sure about is the 150 x 150 being a nominal 6 inch square post. B-)

I'm not a great fan of concreting in timber posts, unless the bottom of the post is left open to let any water out. Otherwise the post ends up sitting in the water contained by the enclosing concrete. A decent bit of timber well treated will last in the ground anyway. You don't see telegraph poles set in concrete. B-)

[Guy King]

The message from "Dave Liquorice" contains these words:

I saw a website about power stations a few days ago proudly claiming outputs in the order of hundreds of milliwatts.

And this bunch, who really ought to know better since they're in the business of explosive devices seem confused about Joules. I suspect it would be hard to make an explosive device that liberated only 6 to 9 milliJoules. A mistake repeated through the document.

(page 6)

Nice toys though. But alarming when you read "The slug impacts with approx 13 - 15mj energy that is accurate to at least 60 metres. A free-fired BD 318 could result in the slug traveling more than 5 kilometres."

[Dave Fawthrop]

|On Tue, 06 Jun 2006 13:24:49 +0100, Steve Lowe wrote: | |> I'm doing a bit of hard landscaping in the back garden putting in some |> Marshall's woodstone posts and sleepers. the posts are 150x150mm x |> 600m long and need 200mm of their depth concreting in. | |Care to look at you units? A 600 metre post (some post!) with only 200 |milli metres in the ground? The only thing I'm moderately sure about is |the 150 x 150 being a nominal 6 inch square post. B-) | |I'm not a great fan of concreting in timber posts, unless the bottom of |the post is left open to let any water out. Otherwise the post ends up |sitting in the water contained by the enclosing concrete. A decent bit of |timber well treated will last in the ground anyway. You don't see |telegraph poles set in concrete. B-)

But you see a lot of ex-telephone poles much worse for wear on the back of lorries. The one which carries our phone line bit the dust after only 45 years.

[Owain]

Cheap modern crap innit.

Owain

[Steve Lowe]

Apologies for the units error - posts are concrete !! the clue is in the name WoodSTONE !!

I agree with you about timber posts - I always coat timber posts with a bitumen type paint and wrap them in polythene and have gravel at the bottom of the hole

TTFN

Steve.

- Steve Lowe

- E-Mail : [e-mail]

- Before Replying Remove .NO.SPAM

- UK Resident although my e-mail address is usa.net