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Posted: Sat Apr 24, 2010 8:17 pm
by mo-uk
Hi
When pointing between Sandstone has set how hard is it meant to be?
rock solid or should it crumble way is, for example, you ran a screwdrivers sideways down it (with not too much force)
Presumably you shouldn;t be able to make it crumble with just your fingernails?
Is the strength decided by how much cement goes in?
Posted: Sat Apr 24, 2010 8:26 pm
by lutonlagerlout
normally you would point witha 3:1 sand : cement ratio mix
and within 24 hours it should be solid and hard to the touch
if it is crumbly it is a fail
cheers LLL
Posted: Sat Apr 24, 2010 11:04 pm
by mickg
yes the strength is decided by the cement content but also the amount of water to bind it all together plays a large part too
I agree with Luton a 3:1 mix of 3 parts and one part cement, its advisable to gage the amount exactly so the colour is consistent with each mix you make
the amount of water required will vary on the moisture content within the sand, it need to be enough water so the mix does not slide off a trowel when held upside down, if its too wet you will stain the flags whist pointing and if its too dry you will have the same problem as you have got now where the following day you can crumble it with your fingers
Posted: Sat Apr 24, 2010 11:12 pm
by mo-uk
thanks for the reply
some pointing was done but i was only looking at it after 2 hours, so will see what its like tomorrow.
Posted: Sun Apr 25, 2010 3:28 pm
by mo-uk
Does the amount of sand decide how dark it is?
i.e the MORE sand the lighter the colour
Posted: Sun Apr 25, 2010 4:09 pm
by lutonlagerlout
to an extent mo,different cements make different colour mortars,same with sand
have you got a picture?
LLL ???
Posted: Sun Apr 25, 2010 6:09 pm
by mo-uk
Hi
Pointing seems to have gone hard today
The issue is that the person that did some pointing is no longer available. the original sand and cement is still there but unsure of the mix to enable exactly the same colour
How hard is it to take out old pointing and redo it again to ensure same colour? how much would you have to 'dig out'?
Posted: Sun Apr 25, 2010 8:33 pm
by lutonlagerlout
the most important thing is to get the same cement and sand,then get the mix right
without seeing it i couldn't guess
a picture would be handy
cheers LLL
Posted: Mon Jun 21, 2010 4:51 pm
by mo-uk
bump...
I had a try and the pointing i got is significantly darker than what i wanted, it has been roughly 2 days - will it go any lighrt?
i used 4 buckets of sand and 1 bucket of cement (small bucket mind)
question - can the amount of water you use affect the colour? or is that irrelevant once it dries?
also is it possible for me to just mix up some mmortar and let it go hard to see the final colour or does it need to be 'in situ' to more accuratley relfect what it will end up as?
Posted: Mon Jun 21, 2010 9:23 pm
by GB_Groundworks
sand
cement
mixing all has an affect on the colour
we have very light sand up here, almost golden with buxton cement makes a light grey mortar
get the orange sand from travis and you get a much darker mortar
Posted: Mon Jun 21, 2010 11:44 pm
by mo-uk
hmm well i am using mastercrete cement and wickes sand. that was what was used before
i am sure it took a ocuple of days to proper lighten up last time but the new stuff i put down is significantly darker than what is down.
Posted: Tue Jun 22, 2010 9:27 pm
by mike builder/landscaper
i use the easypoint guns and my mix is 3/1 sand and cement plus half a bucket of lime per mix. plus a little bit of colour buff/black depending on what customer wants light or dark. all mixes are measured by buckets and sets rock solid within 1 day.
Posted: Tue Jun 22, 2010 10:31 pm
by lutonlagerlout
do you think the lime aids plasticity mike?
I have used a fair bit of easipoint but whenever i see lads trying to use normal mortar it separates in the gun
did 10 m of brickwork yesterday ,already raked out to 25mm
3 bags of easipoint did the job,but crikey it went off like lightning in the heat
LLL
Posted: Wed Jun 23, 2010 7:35 am
by cookiewales
lutonlagerlout wrote:do you think the lime aids plasticity mike?
I have used a fair bit of easipoint but whenever i see lads trying to use normal mortar it separates in the gun
did 10 m of brickwork yesterday ,already raked out to 25mm
3 bags of easipoint did the job,but crikey it went off like lightning in the heat
LLL
hi luton i tried to make my own years ago broke two guns with the effort to get it out instarmac gunpoint same as easy point but does not go of so fast and cheaper 11pound a bag 20kg ie55pence kg cheers cookie :;): :;):
Posted: Wed Jun 23, 2010 6:52 pm
by mike builder/landscaper
yes. the lime gives the mortar a little bit of elasticity and makes it very easy to go through the gun. when we do fireplaces we always add lime to the mix to give the mortar flex between warm and cold and i think it works well with patio pointing because of the varying temps through the seasons. stood up very well in extreme cold this winter as well,no phone calls for return work.