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[?]Concrete fence post repair - is there a suitable filler?

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Dave Chapman

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Jun 27, 2014, 7:12:25 AM6/27/14
to

I have a concrete fence post which has cracked, although at the
moment it still supports the fence, see the two pictures at:-

http://www.minda.co.uk/files/concretepost01.jpg and...

http://www.minda.co.uk/files/concretepost02.jpg

Digging out the post to completely replace it will be a real pain
since it is set in a concrete base so I was wondering if there is a
suitable filler that I can purchase and then 'pour' into the cracks to
reinforce the post and prevent further crumbling.

Any thoughts/suggestions will be much appreciated.

TIA - Dave.

Onetap

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Jun 27, 2014, 8:08:35 AM6/27/14
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On Friday, June 27, 2014 12:12:25 PM UTC+1, Dave Chapman wrote:
> I have a concrete fence post which has cracked, although at the

> TIA - Dave.

You can get an epoxy-based repair mortar, probably Screwfix or similar. Never used it. ISTR that epoxy-based flooring required careful preparation of the old screed to ensure it stayed stuck.
I suspect it'd cost more than a new post and I doubt that it will stay repaired for long. But you know that. Best of luck with it.

Tim Watts

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Jun 27, 2014, 8:38:14 AM6/27/14
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Sorry - it's buggered. No amount of "repair" will help there sadly..

JimK

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Jun 27, 2014, 8:44:18 AM6/27/14
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+1

Jim K

Ian Jackson

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Jun 27, 2014, 11:11:00 AM6/27/14
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In message <f0ac007f-125c-4d28...@googlegroups.com>,
Onetap <one...@talk21.com> writes
Alternatively mix some cement powder with ordinary resin?

I think I'd first fill the cracks and gaps in the sides of the post (and
against the fencepost) with grey car repair paste - fairly stiff, so it
doesn't penetrate too far, then pour resin in from the top. In parts,
you could temporarily glue on some cardboard 'shuttering'*.

You may have to use a little cunning to avoid too much resin oozing out
on the fence post side. Maybe you could first prepare some resin with a
lot of hardener in it (so it goes off quickly), and then dribble that
down on the post side only. As it starts to harden, keep topping it up.
* I think that's the correct description.

If you make a decent job of it, the post will probably long outlast the
fence!
--
Ian

RobertL

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Jun 27, 2014, 11:20:33 AM6/27/14
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On Friday, June 27, 2014 12:12:25 PM UTC+1, Dave Chapman wrote:
> I have a concrete fence post which has cracked, although at the

What about 'cementitious grout' - the kind of thing you pour on concrete so that it flows flows under steelwork bases. You'd need to make a sort of wooden mould around the post an then pour it in. it's quite runny so it would spread into the cracks a bit.

http://www.netweber.co.uk/construction-mortar-products/products/precision-grouting/five-star-grout.html

Robert



Lee

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Jun 27, 2014, 11:47:52 AM6/27/14
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What the others said, although a couple of those large metal "cable
ties" (road sign type) wrapped around it might just about keep it in one
piece for a while longer.

Martin Brown

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Jun 27, 2014, 12:05:58 PM6/27/14
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You might be able to extend its life slightly by either epoxy filler or
the cheaper alternative of slightly expanding high tack polyurethane
glue in the gaps. Basically whatever you do the rusting process will
continue and widen the gap probably sooner rather than later.

--
Regards,
Martin Brown

Dennis@home

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Jun 27, 2014, 1:46:00 PM6/27/14
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On 27/06/2014 13:38, Tim Watts wrote:
That can't be true, they have repaired bridge supports with similar
problems.

It needs a new post casting around the old one.

Easier to dig it out.

Tim Watts

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Jun 27, 2014, 1:50:16 PM6/27/14
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Buggered in any meaningful way... It's not supporting a bridge - the
cost of removal is tiny compared to the cost of removal of a broken
bridge column with a bridge on top...

> It needs a new post casting around the old one.
>
> Easier to dig it out.

yep...

Peter Parry

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Jun 27, 2014, 1:58:12 PM6/27/14
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On Fri, 27 Jun 2014 12:12:25 +0100, Dave Chapman <da...@minda.co.uk>
wrote:

> Digging out the post to completely replace it will be a real pain
>since it is set in a concrete base so I was wondering if there is a
>suitable filler that I can purchase and then 'pour' into the cracks to
>reinforce the post and prevent further crumbling.

Not really, the post is cracking because the vertical iron reinforcing
bar is rusting along its length (as it seems are the horizontal bolts
fixing the fence). When Iron turns to Rust (Iron oxide) it expands
and this cracks the concrete. You can't keep out the water as the bar
has probably now corroded to its base so it will continue to expand
and crack any repair no matter what you plaster on top. The strength
of the post is in the iron bar, not the concrete.

The Medway Handyman

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Jun 27, 2014, 2:44:31 PM6/27/14
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Yup! Buggered!


--
Dave - The Medway Handyman www.medwayhandyman.co.uk

Capitol

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Jun 27, 2014, 3:54:10 PM6/27/14
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Easy. Crack the concrete away from the iron bits, you don't need to go
much lower than the bottom bolt. It will ideally look a bit castellated
and give a good key. Give the iron a thin coat of bitumen and cast a
new post in situ but 2 inches taller to cover the iron. You only need to
shutter 3 sides and there's enough iron around to give adequate
strength. Some neat cement on the join with the original post will
probably help, as will a coat of bitumen on the top of the rebuilt post.

Rick Hughes

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Jun 27, 2014, 4:13:17 PM6/27/14
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To repair with resin and expect it to be strong ... I think not unless
you grind out cracks to provide clean surface.
If it were me (and I didn't want to replace) I'd fill with resin bolt
fix material (something like Fischer Polyester Styrene-Free Resin) ,
then bolt on a support strap of 9mm thick galv steel on the face that
takes most of tension forces ... fixing strap with resin bolts to
avoiding bursting by expanding bolts.

--
UK SelfBuild: http://uk.groups.yahoo.com/group/UK_Selfbuild/

Rod Speed

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Jun 27, 2014, 4:46:51 PM6/27/14
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"Peter Parry" <pe...@wpp.ltd.uk> wrote in message
news:mlbrq99qkc4ptjekc...@4ax.com...
Yes, but given that the strength is undoubtedly in the iron bar
and its likely only surface rust on a quite solid bar, all you really
need to do is end up with some way of stopping any more
water rusting the bar anymore and it will last forever. A decent
waterproof filling of the cracks in the concrete should work fine.

stuart noble

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Jun 28, 2014, 4:39:23 AM6/28/14
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Why styrene free? Ordinary car body filler would suffice, or Toolstation
Profil. Might need to do it again in 10 years time :-)

John Rumm

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Jun 28, 2014, 5:48:20 AM6/28/14
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On 27/06/2014 12:12, Dave Chapman wrote:
>
Its shagged, and replacement is probably the easiest solution IMHO. If
you are worried about the base, you could use a metal bolt down base
support instead.

Clomp it a few times with a club hammer to knock the concrete off, and
use an angle grinder to cut off the rebar etc flush with the ground.
Drill and fix post base to the concrete path, and drop the new post in.

--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

stuart noble

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Jun 28, 2014, 7:43:06 AM6/28/14
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On 28/06/2014 10:48, John Rumm wrote:
> On 27/06/2014 12:12, Dave Chapman wrote:
>>
>> I have a concrete fence post which has cracked, although at the
>> moment it still supports the fence, see the two pictures at:-
>>
>> http://www.minda.co.uk/files/concretepost01.jpg and...
>>
>> http://www.minda.co.uk/files/concretepost02.jpg
>>
>> Digging out the post to completely replace it will be a real pain
>> since it is set in a concrete base so I was wondering if there is a
>> suitable filler that I can purchase and then 'pour' into the cracks to
>> reinforce the post and prevent further crumbling.
>>
>> Any thoughts/suggestions will be much appreciated.
>
> Its shagged, and replacement is probably the easiest solution IMHO. If
> you are worried about the base, you could use a metal bolt down base
> support instead.
>
> Clomp it a few times with a club hammer to knock the concrete off, and
> use an angle grinder to cut off the rebar etc flush with the ground.
> Drill and fix post base to the concrete path, and drop the new post in.
>
+1
Digging out 25 kgs of concrete base is indeed a pain, and what do you do
with it if you do manage to get it out without breaking your back? Take
it down the tip and pour in a fresh 25kgs? Yep, those bolt down bases
are a godsend

JimK

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Jun 28, 2014, 11:54:51 AM6/28/14
to
in the act of breaking it out it will get er broken....

"hardcore" free to good home....

can you use bolt down post bases for concrete posts or just wood?

Jim K

Andrew Mawson

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Jun 28, 2014, 3:52:01 AM6/28/14
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"harryagain" wrote in message news:loljvg$6d5$1...@dont-email.me...
>
>
>"Capitol" <sp...@wher.eva.co.uk> wrote in message
>news:3PydnfWB4ff0VjDO...@brightview.co.uk...
>It has cracked because there is insufficient concrete cover over the
>reinforcing.
>50mm is the min. cover to prevent this happening.
>It doesn't rust (when properly covered @50mm) due to the alkalinity of the
>concrete.
>When not properly covered, acidic rainwater causes the reinforcing to rust,
>the swelling effect shatters the concrete.
>It is buggered and can't be fixed.
>
>The above about bitumen is drivel.
>Concrete bonds to steel, that is what gives reinforced concrete it's
>strength.
>

+1

With a Kango it's an hours work to chop out the old, open up a socket in the
slab, slip in the new and bed it with concrete. Any 'repair' to that post
will be a waste of time and money

Andrew

harryagain

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Jun 28, 2014, 1:31:25 AM6/28/14
to

"Capitol" <sp...@wher.eva.co.uk> wrote in message
news:3PydnfWB4ff0VjDO...@brightview.co.uk...

Capitol

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Jun 28, 2014, 5:31:33 PM6/28/14
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harryagain wrote:

> The above about bitumen is drivel.
> Concrete bonds to steel, that is what gives reinforced concrete it's
> strength.
>
>

Never heard of epoxy coated rebar then? Fence posts frequently use
smooth steel rod, with the end folded into a U shape. It's the ends
which provide the location strength, there is very little bond to the
rod. Two bolts run through this post, they'd benefit from a bit of slip
if you ever had to remove them.

ARW

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Jun 29, 2014, 2:54:07 PM6/29/14
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"Tim Watts" <tw_u...@dionic.net> wrote in message
news:m6508b-...@squidward.local.dionic.net...
The correct technical term is "fucked".

--
Adam

Dave Chapman

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Jul 8, 2014, 3:58:46 AM7/8/14
to

>>>> I have a concrete fence post which has cracked, although at the
>>>> moment it still supports the fence, see the two pictures at:-
>>>>
>>>> http://www.minda.co.uk/files/concretepost01.jpg and...
>>>>
>>>> http://www.minda.co.uk/files/concretepost02.jpg
>>>>
>>>> Digging out the post to completely replace it will be a real pain
>>>> since it is set in a concrete base so I was wondering if there is a
>>>> suitable filler that I can purchase and then 'pour' into the cracks to
>>>> reinforce the post and prevent further crumbling.
>>>>
>>>> Any thoughts/suggestions will be much appreciated.


> Easy. Crack the concrete away from the iron bits, you don't need to
> go much lower than the bottom bolt. It will ideally look a bit
> castellated and give a good key. Give the iron a thin coat of bitumen
> and cast a new post in situ but 2 inches taller to cover the iron. You
> only need to shutter 3 sides and there's enough iron around to give
> adequate strength. Some neat cement on the join with the original post
> will probably help, as will a coat of bitumen on the top of the rebuilt
> post.

Many thanks for that practical suggestion. For the cost of a small
bag of ready-mixed concrete and a bit of shuttering here's the result
and I'm well pleased with it:-

http://www.minda.co.uk/files/concretepost03.jpg

All the best - Dave.



Andy Burns

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Jul 8, 2014, 4:18:28 AM7/8/14
to
Dave Chapman wrote:

> For the cost of a small bag of ready-mixed concrete and a bit of
> shuttering here's the result and I'm well pleased with it:-

Sounds good

> http://www.minda.co.uk/files/concretepost03.jpg

404 unfortunately

JimK

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Jul 8, 2014, 4:21:04 AM7/8/14
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OK for me...

Jim K

Andy Burns

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Jul 8, 2014, 4:22:41 AM7/8/14
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JimK wrote:

> OK for me...

It is *now*

Tim Watts

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Jul 8, 2014, 4:25:12 AM7/8/14
to
On 08/07/14 08:58, Dave Chapman wrote:
>
> http://www.minda.co.uk/files/concretepost03.jpg

Nice result!

Andy Burns

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Jul 8, 2014, 4:25:23 AM7/8/14
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Give it a quick rub-down with an angle grinder and the job's a good'un.

JimK

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Jul 8, 2014, 7:01:50 AM7/8/14
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/Andy Burns
Give it a quick rub-down with an angle grinder and the job's a good'un/q

I'd be inclined to let it cure for a few weeks before setting the ag on it... or just paint with yoghurt / cowsh1t and let nature tone it down for you?

Jim K

Rod Speed

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Jul 8, 2014, 7:56:47 AM7/8/14
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Andy Burns <usenet....@adslpipe.co.uk> wrote
Works fine here.

flamet...@gmail.com

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Feb 16, 2016, 7:53:36 PM2/16/16
to
On Friday, June 27, 2014 at 4:12:25 AM UTC-7, Dave Chapman wrote:
> I have a concrete fence post which has cracked, although at the
> moment it still supports the fence, see the two pictures at:-
>
> http://www.minda.co.uk/files/concretepost01.jpg and...
>
> http://www.minda.co.uk/files/concretepost02.jpg
>
> Digging out the post to completely replace it will be a real pain
> since it is set in a concrete base so I was wondering if there is a
> suitable filler that I can purchase and then 'pour' into the cracks to
> reinforce the post and prevent further crumbling.
>
> Any thoughts/suggestions will be much appreciated.
>
> TIA - Dave.

I have an idea. cover the post tightly with heavy chicken-wire epoxy it at few points, form around and pore epoxy based concrete to shape.

David

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Feb 17, 2016, 4:07:09 AM2/17/16
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Ah - half term and bored?



--
Windows 8.1 on PCSpecialist box

Vir Campestris

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Feb 21, 2016, 12:17:06 PM2/21/16
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On 17/02/2016 09:07, David wrote:
> Ah - half term and bored?

Suspect he didn't notice the date on the OP.

Andy

Jomo

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May 25, 2018, 7:44:05 AM5/25/18
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replying to Capitol, Jomo wrote:
Does this mean you shutter the original post?

--
for full context, visit https://www.homeownershub.com/uk-diy/concrete-fence-post-repair-is-there-a-suitable-filler-980934-.htm


Brian Gaff

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May 25, 2018, 10:35:06 AM5/25/18
to
posted on June 27, 2014, 11:12 am
I have a concrete fence post which has cracked, although at the moment it
still supports the fence, see the two pictures at:-
concretepost01
http://www.minda.co.uk/files/concretepost01.jpg and...
concretepost02
http://www.minda.co.uk/files/concretepost02.jpg
Digging out the post to completely replace it will be a real pain since it
is set in a concrete base so I was wondering if there is a suitable filler
that I can purchase and then 'pour' into the cracks to reinforce the post
and prevent further crumbling.
Any thoughts/suggestions will be much appreciated.
TIA - Dave.


Hmm, yet another lamb to the slaughter of the weird year ignoring home
owners club portal to usenet.
I have had a post split for longer than this and its still holding
together, and actually looks quite rustic, as apposed to rusty where the
metal is!
grin
Brian
--
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Blind user, so no pictures please!
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news:7GSNC.165103$jb7....@fx34.am4...

kentw...@gmail.com

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Jun 17, 2020, 3:25:39 AM6/17/20
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On Friday, 27 June 2014 12:12:25 UTC+1, Dave Chapman wrote:
> I have a concrete fence post which has cracked, although at the
> moment it still supports the fence, see the two pictures at:-
>
> http://www.minda.co.uk/files/concretepost01.jpg and...

Brian Gaff (Sofa)

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Jun 18, 2020, 8:11:37 AM6/18/20
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2014?
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
bri...@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
<kentw...@gmail.com> wrote in message
news:dc1a27fe-2283-4151...@googlegroups.com...

amoh...@gmail.com

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Jun 27, 2020, 10:23:05 AM6/27/20
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Hello!

Posting to an old thread here, with a new similar question. Original photos no loner online so cannot see how relevant my situation is, my own photos are on the same question posted to the MSF here:

https://forums.moneysavingexpert.com/discussion/6162047/demolishing-or-really-grinding-a-concrete-fence-post-instead-of-extracting-it#latest



I have a broken concrete fence post. Having looked at various forums, it looks like the best thing to do is to dig it out and replace. There are also a few threads about fixing with epoxy, jacketing the post, etc. Unfortunately I cannot dig as I have a sick tree at risk of falling on lots of things, situated practically next to the post and whose roots I do not want to disturb until it is felled in November.

As you can see in the photos, the post has essentially been snapped off at the base (a large dead branch fell on it) so any repairs unlikely to last long.

So my question is, has anyone tried demolishing/breaking what is left of the post and its concrete anchor in the ground? I am thinking that I need to break enough concrete to make room for a new post. I will then need only a little more concrete to fix it to the existing ground anchor.

I am thinking of an electric breaker like https://www.hss.com/hire/p/breaker-vibration-damped-110v

Is there any reason this would not work? I realise the existing post’s rebars will be a little in the way but should be able to work around them. Hopefully not have to move the gravel boards either.

Thank you!

tabb...@gmail.com

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Jun 27, 2020, 1:51:12 PM6/27/20
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Surely it's cheaper to buy an sds drill than hire.
Could you make life easier by waiting until the tree goes?
As for repairing it, no way really. You can cast new crete on but it won't last.


NT

amoh...@gmail.com

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Jun 27, 2020, 4:14:35 PM6/27/20
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Well I am assuming I can do it in a couple of hours (if that) with a dedicated breaker costing me about £35 per day. The cheapest dedicate breaker to buy is about £150.which is obviously much better value for money, but I just can’t imagine ever needing a proper breaker again, hence the rental idea. I can buy a sds hammer drill combination which would be more useful in future, but not sure how long it would take to punch a hole in the concrete with a light machine.

All the same, apparently it is still really hard work even with a large dedicated demolishing hammer...

Ideally I will try to remove he tree sooner, but I am at the mercy of tree surgeons...

Roger Hayter

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Jun 27, 2020, 6:14:05 PM6/27/20
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I think it is exceedingly unlikely that you would be able to make a hole
in the concrete base around the old post without cracking the whole
base. Tthe centre is strongly supported in compression by the
periphery. The only thing that might be possible is a stitching circle
of drilled holes all the way round the post and right the way through
the concrete base. But even then breaking the concrete between the
holes with a long chisel enough to extract the post would be hard. And
at some point in this process the base is going to split. It would be
much harder than breaking up the base from the periphery, which you
apparently don't want to do for fear of disturbing the tree,


--

Roger Hayter

The Natural Philosopher

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Jun 28, 2020, 2:50:12 AM6/28/20
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I managed to dig up a really deep chunk of concrete using a concrete saw
hired for the day. Once split into pieces its came apart and could be
pulled out with a pick.




--
"When a true genius appears in the world, you may know him by this sign,
that the dunces are all in confederacy against him."

Jonathan Swift.

tabb...@gmail.com

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Jun 28, 2020, 12:54:20 PM6/28/20
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If I can buy a cheap sds for £35 or hire one for £35 I'd always buy. (I don't know what cheap SDS currently cost). Even a basic sds can get through concrete.

If you want to wait until the tree is done, a concrete patch up should last that long. It just won't last well.


NT

charles

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Jun 28, 2020, 1:49:09 PM6/28/20
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In article <8fea254e-e5db-41b6...@googlegroups.com>,
<tabb...@gmail.com> wrote:
> On Saturday, 27 June 2020 21:14:35 UTC+1, amoh...@gmail.com wrote:

> > Well I am assuming I can do it in a couple of hours (if that) with a
> > dedicated breaker costing me about £35 per day. The cheapest dedicate
> > breaker to buy is about £150.which is obviously much better value for
> > money, but I just can‘t imagine ever needing a proper breaker again,
> > hence the rental idea. I can buy a sds hammer drill combination which
> > would be more useful in future, but not sure how long it would take to
> > punch a hole in the concrete with a light machine.
> >
> > All the same, apparently it is still really hard work even with a large
> > dedicated demolishing hammer...
> >
> > Ideally I will try to remove he tree sooner, but I am at the mercy of
> > tree surgeons...

> If I can buy a cheap sds for £35 or hire one for £35 I'd always buy. (I
> don't know what cheap SDS currently cost). Even a basic sds can get
> through concrete.

cheapest in Screwfix = £50.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

amoh...@gmail.com

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Jun 29, 2020, 9:31:24 AM6/29/20
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Thank you for all the comments. Looks like I will patch until the tree is gone. Then I will attack the postcrete from outside the blob.
When it come time to do this, I will still hire a large breaker than buy a small one though. I cannot imagine a 4kg sds hammer drill having the same destructive efficiency as a 20kg machine. A bit like a big sledge hammer v.s. a small one. A small one will do the job, but eventually. Whilst (I am hoping) a 20kg machine will be just that bit faster.

The Natural Philosopher

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Jun 30, 2020, 3:47:25 AM6/30/20
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I remember once having ruined a slab of sandstone, and taken nearly two
hours to cut another one with a diamond tile cutter, the time taken to
go into the town, hire a serious industrial angle grinder with a
diamond blade, get back, cut the stones and return the grinder ("Was
there something wrong with it mate?) was less than an hour...

...on the other hand after spending more on hiring a tile cutter than
one cost, I bought one...

Cost benefit analysis rules, OK?

--
"The most difficult subjects can be explained to the most slow witted
man if he has not formed any idea of them already; but the simplest
thing cannot be made clear to the most intelligent man if he is firmly
persuaded that he knows already, without a shadow of doubt, what is laid
before him."

- Leo Tolstoy

tabb...@gmail.com

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Jun 30, 2020, 7:59:30 AM6/30/20
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On Tuesday, 30 June 2020 08:47:25 UTC+1, The Natural Philosopher wrote:
> On 29/06/2020 14:31, amoh...@gmail.com wrote:

> > Thank you for all the comments. Looks like I will patch until the
> > tree is gone. Then I will attack the postcrete from outside the
> > blob. When it come time to do this, I will still hire a large breaker
> > than buy a small one though. I cannot imagine a 4kg sds hammer drill
> > having the same destructive efficiency as a 20kg machine. A bit like
> > a big sledge hammer v.s. a small one. A small one will do the job,
> > but eventually. Whilst (I am hoping) a 20kg machine will be just
> > that bit faster.
> >
> I remember once having ruined a slab of sandstone, and taken nearly two
> hours to cut another one with a diamond tile cutter, the time taken to
> go into the town, hire a serious industrial angle grinder with a
> diamond blade, get back, cut the stones and return the grinder ("Was
> there something wrong with it mate?) was less than an hour...
>
> ...on the other hand after spending more on hiring a tile cutter than
> one cost, I bought one...
>
> Cost benefit analysis rules, OK?

Indeed. I'd not expect a standard SDS & drill bit to have any particular difficulty breaking up a concrete post though, so I'd get the SDS.


NT
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