Bolt down fence post shoes

[AndrewSchofield]

Hi guys, my first post in the gardening section!! Hope this is in the right forum?

We're just about to erect a fence on top of a concrete yard. We've bought some bolt-down fence post shoes to bolt directly onto the concrete but can anyone advise what bolts/fixings i should to fix these to the concrete?

 

[^neo^]

Chemical resin and studs.
Screwfix should do some decent sized tubes that will sort you out, otherwise travis perkins and the likes charge over a tenner for a tube that fits in a standard mastic gun (think we pay about £4 a tube for the big ones, but also need the big gun for it)
Once it's in, it'll never come out!

 

[roberta1000]

Yes, as said, resin and studs should be fine.

Main thing first is to check the thickness and quality of the concrete base especially if you're thinking of a 2m fence or such which will exert a lot of leverage. You really need several inches of concrete and hard enough that you can't easily break it with a hammer and chisel.

 

[AndrewSchofield]

Thanks for the advice. The conrete is at least 4inches thick and if it was put in place by the same people who did the base for the pre-fab garage i deolished a couple of years back then it'll take some serious sledgehammer pounding to break it up!!

The fence is approximately 4ft6in high.

 

[Thermo]

whatever you use, make sure they are easy to unbolt. Boltdown Metposts can and do sheer under high wind loads.

 

[AndrewSchofield]

Just to add - never used resin fixing before. Do i put the resin in, then push the bolt/stud into it and let it set or do i put the bolt/stud in and put the resin afterwards?

Or are neither of these methods correct?

 

[Thermo]

yes, but blow the hole clear of dust first, otherwise it will just stick to the loose dust

 

[AndrewSchofield]

yes, but blow the hole clear of dust first, otherwise it will just stick to the loose dust

Cheers Thermo - but which method?? Or can i do it either way?

 

[Thermo]

resin first. keep it off your fingers. Youll have a nightmare doing it the other way around

 

[AndrewSchofield]

Cheers - take it it doesn't come off the skin? Might get the missus to do that bit - she's the one that wants a new fence!!!

 

[Thermo]

it does, after a few weeks! wear some gloves when you do it. We normally used the resin that comes in smal glass vials. Pop them in the hole, put the bolt and tap it to break the glass.

 

[AndrewSchofield]

And something else thats just occured to me - how much space do i need in the hole? If i'm using M8 studs will a 9mm hole do? 10mm? Or does the resin need a bit more space than that?

 

[Thermo]

keep it simple and stop getting over technical about it. its no different to glueing a wooden peg in a hole. drill the same size diameter hole as the rod. fill it with resin and push it in.

 

[AndrewSchofield]

Thanks Thermo - its just like gluing a wooden peg in a hole with one exception - i've used wood glue before - never even seen Resin before!! It appears its not cheap stuff so don't wanna buy it then screw it up by doing it wrong. Will follow your directions and i'm sure i'll soon be a resin fixing pro!!!

 

[^neo^]

M8 studs = 10mm hole.
Dont drill right through the concrete or the resin will just be pushed out the other side when you put the stud in.
Twist the stud as it goes in too.
If at all possible, i'd open the holes up to 10mm in the metpost and use 10mm studs (12mm hole) for some serious strength!

The other thing i forgot to say is, when you use the resin it is (generally) a 2 pack system which mixes in the nozzle as it comes out. When using a new nozzle, squirt a couple of inches of it out to make sure it's mixed (should see a colour change) or it'll never go off!. Get some spare nozzles too as in this weather you'll only get about 15 minutes before it's gone off.

Don't know what prices you have so far, but have a look at http://www.impactpt.co.uk/product.asp?catID=6&subID=45&prodID=176
The big 380ml tubes should hapilly do 15 10mm holes