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Old August 9th 04, 10:02 AM
Andy Jeffries
Posts: n/a
Default Tips Needed on Plastering

Hi Bodysnatcher,

Here's a document I found on this forum (I believe). It's saved on my
hard drive by the name "Plastering by Patrick.txt" so I guess it was
written by a guy named Patrick - all credit to ya Patrick - it certainly
helped me when I did a small room.

Good luck,



I started my life as an electrician and have been in the building
industry for a long time, graduating to running my own house building
company, so I've probably seen it all and done most of it. These days
I renovate houses for a hobby and, apart from carpet fitting and
plastering, I do it all myself.

I recently decided to alter one of our own bedrooms by putting a
shower in and wardrobes etc. This room hadn't been touched for about
forty years and consequently required a good seeing to. At the end of
the first days work, stripping wallpaper, drinking tea, scratching my
backside and generally getting to know the job I, and my beloved, sat
down for a glass of champagne (as you do)! After two thirds of three
bottles or so she said "Why don't we take out the ceiling and expose
the beams" After two thirds of three bottles or so I thought this was
a tremendous idea and committed myself wholeheartedly.

Next day I raided the medicine chest, ate the aspro and set to work.
Down came the ceiling and resplendent before our very eyes was the
entire underside of the stone slate roof. Four 12 x 12 partly adzed
oak purlins, one humungous truss and a deep deep sense of misgiving.
From floor to apex is approximately eighteen feet and the room is in
the region of eighteen feet long and sixteen feet wide. Another
alteration in this room called for a door to be moved from one side of
the central chimney stack to the other. There were vast quantities of
old plaster which sought refugee status from the walls and hid in one
of the skips I had thoughtfully placed outside the bedroom window. In
short, there was going to be a lot of plastering to do.

Now; I no longer earn my keep by building trade activities and
consequently I am practicing my hobby evenings and weekends. Also,
now that I am getting very old and passion, that ravenous beast, no
longer rears its ugly head as often (apologies to Roger McGough), I
find that one of life's enjoyments is doing my own stuff from start to
finish (or start to carpets in my case). Also, even though I know a
lot of them, actually getting a Spread to come and do the plastering
would be logistically difficult. By nature I am a tight *******, a sad
******* and very probably a demented one (Man City fan, say no more)
to. I decided that for the first time in my life, I am going to
plaster this lot and sod the consequences.

So this is what I did, and you may wish to do too:

First things first. You've never been beaten yet and you're not going
to start now. This may seem trite under the circumstances, and as you
progress down the gypsum road you'll deny thrice (or more) that you
ever said it. But keep it in the back of your mind.

Your particular job, Jim lad, involves a brick wall, which involves a
base or roughing coat interspersed with a banging your head against it
coat followed by a finish coat or skim. If you're lucky you'll omit
the middle coat but don't hold your breath.

Base or Roughing. This involves one of several materials, all of
which do the same job. They provide a base upon which you put your
finish/skim coat. Its object is to provide a reasonably level
background and as such is not meant to be smooth. You just have to get
it reasonably flat, with as few undulations as possible and hopefully
without any craters.

With a brick wall the best (IMO) roughing coat is Carlite Browning.
This comes in large bags which will test your scrotum elasticity
coefficient but which will normally not damage it too greatly.

Lay the bag flat on the floor, get a Stanley knife and cut it open
like a, well like a bag of plaster actually. Whilst you are at B&Q
buying this here plaster, also get yourself a plastic bath to mix it
in. You don't want to be mixing this stuff on the floor, you will
need a container. Plastic baths cost about fifteen squid or so. The
delicate shade of blue they're manufactured in makes them very handy
for the new bathroom renovations later in the year too!

Now, put about five - no more - shovel loads of said browning into the
bath. Make sure you have at least two buckets of water handy and pour
about half of one bucket into the bath with the plaster. With the
front and then the back of the shovel, move the plaster through the
water, back and forth, back and forth until the water and plaster have
meta.. metamor. changed into an unpleasant half wet half dry mixture.
At this stage start to pick it up with the shovel and drop it back
down on itself. i.e. mix it. You won't have added enough water at
this stage so start to add more, slowly until you have a mix
resembling a stiff chicken madras without the chicken. A bit like a
very thick whipped cream.

At this point the stuff is going to start out on it's hour long
journey into rigidity so, time is now of the essence!

If you've not done this before you'll soon discover the one thing you
haven't got is speed. You'll be slow and clumsy, you won't believe
it's possible that this stuff will stick to the wall and you'll begin
to wonder how you can abandon ship and save face at the same time.
Courage mon ami, pretend it's your first lover. Remember how nothing
was going to stop you then and it isn't going to stop you now. Take a
shovel load of the mix and slop it onto your ligger board. (At least
in this part of the world it's called a ligger board. Don't know what
it is where you are but, regardless of name, this is a piece of flat
stuff -22mm MDF is as good as anything- about 3 feet square and placed
at or about waist height (Do not, under any circumstances use
something she cherishes to stand it on)).

Next with your hawk (I guess you do have one of these, it's a square
piece of metal or plastic on a short stick??) in your left hand (or
right hand if you're cuddy-wifted) and your trowel in the other hand,
push a glob of muck (technical expressions tend to creep in) onto the
hawk, about the size of a right hand 48dd (ask the wife if you're
unsure). When it's on the hawk, slide your trowel at an angle of 45
degrees, underneath it, lift it about four inches into the air and
drop it back on the hawk. Do this a few times until you've got the
feel for it. I'm not quite sure what the benefits to the job are but
it feels good to do and lets the muck know you're the boss. It also
produces a very neat rugby-ball shaped pasty on the hawk. Casual
passers by will be enthralled and only you and I will really know the
truth. I digress.

Now, approach the wall and God at the same time. The wall is about to
be transformed, God probably doesn't give a damn but you might just
get lucky. The object is to get this stuff in a fairly even and flat
layer all over the wall. Unless you're a natural born or just get
lucky you're going to need a little help to achieve this.

Some guys advise putting thin wooden battens, vertically on the wall
and then using them as a kind of former by rubbing a levelling stick
across them and scooping off excess plaster. This is a good method
but, if you can manage it, substitute these battens by using plaster.
To do this; when you're at the wall, bend your knees and scoop about
half the rugby ball pasty which is now sitting on your hawk onto your
trowel. The best way to do this is to hold your hawk slightly towards
you and, with the bottom edge of the trowel, scoop away and upwards
with a twist of the wrist at the last minute so that you finish up
with a trowel, flat side up, with a big wodge of fresh muck on it.
(I've found it's best to pretend you do this all the time because if
you so much as flicker an eye, the muck will find out you're a
charlatan and leap onto the floor). If it does this, don't worry,
just try again. If your floor is fairly clean you can scoop up the
spills and re-use them. (This doesn't apply to skimming though).

Once you have the muck on the trowel, push it against the bottom of
the wall (not quite touching the floor) and slide the trowel upwards,
making sure you hold the top edge of the trowel slightly further away
from the wall than the bottom edge. The muck will leave the trowel
and stick to the wall. Do this till you run out of plaster on the
trowel then repeat with fresh stuff until you have a trowel width of
muck all the way up the wall. Repeat this a yard or so to the right
and then the left. Repeat until you have vertical lines of muck up
the wall about a yard or so apart and no muck left on your ligger. At
this point your plaster is hopefully still workable (you'll see what I
mean about speed at this point) so get a straight edge and place it
vertically against the plaster strips and try to level them off so
they're about a quarter to half an inch thick all the way up. If you
need to add bits of muck, add them, play about with it, you're the
boss! When you have them roughly in the required condition, leave them
alone. Go and have a recreational moment (preferably involving the
wife because you're going to need her sense of humour soon) and come
back after about half an hour. Before you go off though you must,
repeat must, repeat must clean your bath, your hawk, your trowel and
your shovel. A bucket of water and a hand brush will be invaluable
here. Under no circumstances neglect this because you'll regret it if
you do.

OK. Much refreshed , or not as the case may be, we're back. Do
another mix in your clean bath with your clean shovel. About the same
amount as before, or less if you feel that was too much. Practice the
art of muck chucking and rugby ball pasty making again to increase
your confidence level, fill up your hawk and return to the wall.
Start to spread the muck between two of the vertical strips. Fill it
up, proud if you can, all the way to the top. By this time the strips
will be hard enough to be masquerading as formers, so get a feathered
straight edge and, starting at the bottom place the straight edge
across the enclosing strips and in a sawing motion move the straight
edge from side to side and up from bottom to top. Place the excess
back on the ligger. Look at the job. You'll probably see bits you've
missed, probably all over the place. No worry. Just fill them, saw
them, look at them. Fill them, saw them, look at them. Pretty soon
you won't have any holes, just a reasonably flat surface between the
strips. Do it again and again until you have a wall with a roughing
coat on it. Congratulations.

Wait for half an hour to an hour and with the corner of your trowel
scratch a diamond pattern on it so you have a key for the skim coat.
Oo's a clever boy then?

Take the rest of the day off (it's probably ten o'clock in the evening
by this time anyway) and next day we'll skim it. Just like this:

If you've used Carlite Browning or any of the light weight roughing
plasters you will probably be as well using Carlite Finish. Same
scrotum elasticity coefficient as before but a much finer consistency
of muck and a bit of a bugger if you don't watch it.

You will need two buckets, one for water and one for mixing, a hawk, a
plasterer's trowel, a gauging trowel, a mixing whisk and electric
drill, clothes you can throw away this evening (or whenever you
finish) and a hand brush, preferably with soft pier sava (spelling?)

If you have left the roughing for more than a couple of days, get a
garden spray, wet it down and allow it to soak in a little. I'm not
sure this is essential because I've seen Spreads just walk in and do
dry walls but it felt better to me.

The object of this exercise is to put two coats of skim onto the
rough. The first coat fills in the small holes in the rough backing
coat and gives a key to the second coat which is applied second
(funnily enough) and then 'polished'.

Don't even consider doing it in one coat. It's no fun and anyway you
could catch a cold (sorry).

With skim coats, cleanliness is essential. As is a consistency of
mix. The last thing you want is bits of dirt or lumps of unmixed
plaster in your skimming. Start by putting clean water into a clean
bucket. I wouldn't put more than two inches in the bottom of a
standard builders bucket to start with. When you've done this, start
to add your plaster using a small shovel or scoop. One scoop, mix
with the whisk (incidentally you can get these from decent hardware
shops or screw fix for about a fiver and they're absolutely essential
unless you have arms like Arnie) until it's dissolved and then add
another scoop, mix and so on until you have about a third of a bucket
of gloopy pink (or grey) muck in the bucket. Don't get carried away
and mix too much, you'll just finish up throwing it away.

Now, with the aid of the gauging trowel and gravity, tip the muck onto
your ligger. Unless you have a labourer (remember the advice about
recreation and the wife?) stop at this point and quickly clean the
bucket, whisk and anything else that has plaster on it. Do not skip
this under any circumstances.

You now repeat the picking up, slopping down, rugby ball pasty making
exercise you started with yesterday. This time however the muck is
much finer, slippier, sloppier and altogether livelier than yesterday.
Persevere, it's essential you utilise your superior intellect to
subdue the material and get it to do what you want. Word of warning
though. Skim is the knee trembler of gypsum and it's going 'off'
quicker than you think, so subdue it quickly and with panache.

With the pasty on your hawk approach the wall and with the same knee
bend, but this time at the bottom left hand side of the wall (unless
you're cuddy-wifted), same flick of the wrist, same curse, as most of
it (but not all), goes on the floor, get some onto your trowel. Push
the trowel against the wall and in an arcing motion, just spread it.
All you're doing in this exercise is getting a thin coat onto the
wall. As long as it covers it, it'll do.

Depending on how large an area your wall is I would be careful about
trying to do it all at once. If you can first coat an area
approximately four feet square I think you'll have done well. The
problem again is going to be speed. You're going to have to get a
second coat on before the first one has gone completely hard and only
practical experience is going to tell you how big this area can be.
Don't be tempted to try and get this first coat looking like a mirror,
it just has to cover and key. It's the second coat where your skill
will really shine through. This is how:

Mix about the same amount again, same rituals and prayers, same steely
determination. Start in the same place and apply the second coat,
about 2 - 3 mm thick if you can. Again at this stage all you're doing
is covering but try not to get too many 'craters' in it. If you are
doing, just spread a little more on. Keep looking at it (but not to
the exclusion of doing it) and you'll soon get the hang of it. When
you've covered your first coat, leave it for about ten or fifteen
minutes. Clean your tackle while you're waiting. Now with clean hawk
in left hand, clean trowel in right (or not, if you're cuddy-wifted),
clean bucket of water on floor and clean brush in said bucket, set to

Using the edge of the trowel held at an angle of approximately 40 degs
to the wall, drag it over the plaster. You'll soon see what the
effect is. Either it'll gouge out a trough in the newly applied
plaster or it'll remove the application marks and start to smooth it
out for you (exciting). If the former, the plaster is probably too
un-set so wait another ten, if the latter; keep going lad, you'll soon
be on the vinegars! It's now a question of edge troweling until its
all nice and smooth. The longer you go on, the harder the plaster is
getting and the smoother your finish is becoming. If it goes off too
much, don't fret, dip the brush in the water bucket, splash it on the
area you're polishing and it'll buy you some time. Scrape, place on
your hawk and re-use as necessary any plaster that comes off to fill
any craters you may have.

Apart from being on the knackered side you should now start to be
experiencing a rather heady feeling of achievement. You'll be finding
out how to do the edges and corners and amazed at how much pressure
you can apply and still keep a smooth surface. Don't worry too much
about the thin lines appearing at the edge of the trowel, these are
mostly water lines and will disappear. If they don't, a quick once
over with the a sander after your first coat of emulsion will cure

Finally. Clean your tackle, open the champagne and lead your chariots
into Rome. Best of luck.

Patrick (CTID)