On 02/11/10 22:50, sm_jamieson wrote:

What consistency should the grout be ?

Probably a little less stiff than you want - as, at least with the
Mapei, it firms up a notch during the first 5 minutes after mixing.
seems to hold there for another 15 minutes at most (in the pot) and then
rapidly becomes unworkable (though even at 30 minutes you can still use
some for patching small missed bits.

YMMV, probably hugely with manufacturer and type. As I found zero
problems blending in (ie working new grout to grout I did yesterday -
with white grout there isn't much to go wrong) it's probbaly best just
to experiment in a less obvious location - once you've found the right
mix and style of application it speeds up...

You could start the way I did - mix using kitchen scales exactly to the
instructions - at least you know you'll be in the right ballpark, as the
manufacturer intended. It's very sensitive to ratios.

I found a wooden spoon and a stainless kitchen bowl (large one) ideal
for mixing the small quantities I needed on each batch.

In the future I will go for fairly thick (whipped cream or thicker),
not sloppy,
since it then firms up much more quickly in the gaps, ensuring that
you
don't wipe out too much when sponging, and it is spongeable before the
grout film you get sets too much on the tile surface.
Simon.

The fine surface film wasn't a problem IME - a dry polish with kitchen
roll after an hour or three sorts that out. If you are doing coloured
tiles with a bevel edge as I did, a dry kitchen roll at this stage is
just rough enough to smooth the grout off to a nice cut line finish
without damaging the bulk - a fingernail just to clean up any reticent
bits can also work.

If you leave that 24 hours, it becomes *much* harder.

Have the sealant ready too - stick that on as soon as permitted (the
spray ones at least can be applied whilst the grout is still damp after
the polishing. At least before it sees any real world abuse.

Cheers

Tim

--
Tim Watts