Jeff wrote:
On Sat, 25 Aug 2007 13:48:05 +0100, The Natural Philosopher
wrote:
removal of grout from slate tiles
Its murder doing the grouting: If you had posted earlier I would have
told you how I evolved a system...that works.

Just be ultra happy it was slate, not limestone. That etches faster with
the acid than the grout does...

T

Any chance you can enlighten us?

We are just about ready to lay a limestone tile floor in the kitchen
and we've never done this before. Any advice will be most welcome TNP.

TNP's advice to someone about to lay limestone in a kitchen?

DON'T.


On account of just about any acid will attacke it, its porous and it
stains..

HOWEVER if you must...

PEPARATION

1/. Take your time. PLENTY of time, and don't move on till one bit is
finished properly.

2/. I'd probably, with limestone, seal the tops before even starting to
lay, with at least two coats of the expensive Lithofin muckite.

3/. If laying over concrete slabs, use Ardex rapid set tile cement. Its
rubbery in an hour, andd rock hard overnight.

4/ Mix it WELL AWAY from your limestone. Mixing is a mucky job. I use
about a bucket full for a couple of large tiles.

5/. Measure the room carefully and run a string down the longest length
to check for flatness, slope and finished floor height. Take your time.
Yu beed at least 5-6mm of cement to give a good bed for the slabs. I
admit to using up to 30mm on my floor: My excuse was that it wasn;'t a
very good screed job. Use BIG level.

6/. Dry lay any critical bits - sometime you have to adjust your line to
get the tiles parallel to the most obvious features..and try noy to end
up with 10mm wide tile fragments at the edges...

7/. If the floor is very dry and dusty, slop a 50-50 PVA mixture on it a
day or two before laying.

Right thats the prep work. Time to lay the first line.

You need a bucket of cement, a bucket of fresh water, constantly
refreshed by a willing partner, a few packets of tile spacers and about
30 disposables sponges. You also need a spirit level - a smaller one-
and a pointing trowel and a flat blade scraper and a comb type cement
applicator thingie. A rubber mallet is good too.

Putting the tiles down is two parts. Getting them down, and cleaing up
the mess you will inevitably make.

PUTTING DOWN.

I generally on big slabs go one at a time. On smaller tile you can
indeed lay a part row. You should have a string to work to at least till
you get better. Unless your room is dead square do NOT start at one end.
Start somewhere in the middle, and gob a big pat of muckite down where
the tile will go. Try and get it level and correct, them comb it up with
the comb thingie, and splat the tile down.

One of four things will happen.

(a) you got the cement dead right, and a tiny tap gets the tile seated
perfectly with no extra squidging out of the sides, and no slop or rock
and the top[ surface is dead clean. In your dreams. That's what you pay
a pro £200 a day to be able to do. YOU are an amateur, and so am I...

(b) Its proud, and you tap away at it to get it down, and muckite
squidges all out the edges and up between it and the last tile. Don't
panic. On untiled floor areas remove surplus with a square ended
scrapery putty thingie, and use the pointing trowel to run down between
tiles to clear the surplus and leave room for teh grout. You will be
aghast, your wife will be screaming at you as her expensive tiles are
now smeared with cement, and she has visions of this being just another
DIY disaster. Reassure her that this is perfectly normal, and get her t
make a cup of tea or coffee.

(c) its too low, and there is no recourse but to lever the thing up,
getting it filthy, wash the top a bit add more muckite and go for a type
(b) scenario.

(d) its uneven. Ther are bits too hogh, and bits too low..sometimes you
can recover from this by elevering it up a bit and using the flat ended
scrapery thing to force more muckite under one edge. or a ruler to push
stuff sideways under to fill a hollow in the middle.

By the way do NOT use the '5 cowpat' method Maybe pros can get that
right and end up squashing the pats till they JUST touch. Every time
I've used it I've ended up with a 'rocking tile' he on;ly vis you shuld
have are what the scrapery comb thing leaves, ad not a lot of those either.

CLEANING UP.

Right. You have a couple of tiles - maybe three down, your bucket of
cement is empty, and what's in it is starting to go off. And te tiles
are COVRED in nerly as much filthy muckite as your jeans and arms and
legs. I don't to worry you, but you have about 10 minutes to clean up
those tiles or the goo will never come off.

First of all, park all the tools in the bucket and put it out of harms
ways. If assistant present order make tea/coffee, and more cement. You
have work to do.

First wash your hands and scrape the worst off your knees hopefully you
have 'borrowed' some really naff trainers from a teeneage offspring, so
you won't wreck any imporant shoes. Let's face it., Nike and Reebok are
only FIT to lay floors in.

Fill the water bucket with fresh clean water. Put in three or for
sponges and soak

Go via the unlaid floor to where you need to clean. Take a sponge and
squeeze it out and starting at one edge wipe it across the tile ONCE.

Then rinse it thoroughly and repeat. If the cement has gone a little
hard, use the scourer side (white scourers: NOT green) to rub away at
the cement. Use the sponge to remove cement between tiles - or a bit of
stick or trowel so that none will be visible after grouting.

Repeat this endlessly. Use fresh water often. You HAVE to get it all up
with limestone. Cement and limestone are virtually identical chemically:
Anything that takes cement (or grout) off.......:-(

DO NOT be despondent if it takes you twice as long to clean as it did to
lay. Just think how good a shag you will get when its all down. As you
get practiced, you will make less mess..

OK, thats it.

Seal that lot again before grouting.

Grouting is the same nightmare again, only worse, because half the time
you will wipe the grout out of the tile gaps. or get it watery and it
will crack and slump.

You will know every square centimeter of your floor better than you know
your wife, when you have done.

It took me the whole of the memorable last televised test series to lay
my kitchen with slate. I'd do about two square meters, and take a break.
I had 50m^2 to do...

But SWMBO thinks its great and people ask who I got in to do it...so it
can't be that bad...;-)