how to remove paint from brickwork?
Fred
Following advice from this group, I am now staring to paint the inside
of my single skin brick garage with bitumen paint to waterproof it.
But... one wall is already covered in paint. I checked with the
manufacturer of the bitumen paint and they advised removing the
existing paint first. I had hoped I might be able to paint over it ;(
I don't know whether this is masonry paint or emulsion or what because
it was there when we moved in.
I have tried a flap disc in an angle grinder and it does remove most
of the paint but judging from the dust, it is also removing some of
the brick too. I know some people are quick to warn about the dangers
of angle grinders; are flap discs any safer? I presume the danger is
from discs shattering and high speed fragments flying towards the
operator?
I haven't used a wire brush for the same reason; I thought it would
scratch the bricks.
I tried a paint stripper, all I had at home was "yellow" nitromors. It
certainly took the top layer of paint off but the bricks are still
white rather than red, and I have now run out.
So what do you suggest I buy and try next?
A quick google suggested paint stripper but also sand blasting and
pressure washing. The problem would be that I have only emptied half
the garage and moved the rest into the middle, so to pressure wash I
would need to empty it completely. There was a suggestion that
pressure washing would damage the mortar though and this is not good
mortar to begin with. It is quite sandy and I have tried to repoint
where it has crumbled already.
I see you can get sand blaster attachments for pressure washers. Are
they any good? But aren't we back to where we began that any abrasive
will scratch the brick?
TIA
Jim K
<big snip>
> I see you can get sand blaster attachments for pressure washers. Are
> they any good? But aren't we back to where we began that any abrasive
> will scratch the brick?
but if it's inside your garage AND you are going to slap bitumen paint
all over it - why does it matter if it's scratched/abraded? for the
bitumen paint plus whatever else, you *need* a good key (as,
presumably, the manufacturer you spoke to was intimating)?
Jim K
stuart noble
> Hi,
>
> Following advice from this group, I am now staring to paint the inside
> of my single skin brick garage with bitumen paint to waterproof it.
> But... one wall is already covered in paint. I checked with the
> manufacturer of the bitumen paint and they advised removing the
> existing paint first. I had hoped I might be able to paint over it ;(
>
and see on a small area
Fred
<stuart...@ntlworld.com> wrote:
>You probably can, but no manufacturer is going to tell you that. Suck it
>and see on a small area
Hi. I have had since another email from a different manufacturer of
bitumen paint; this manufacturer has said you can over paint, so now I
don't know who to believe! I think your suggestion of trying a small
area is the only way to see.
In reply to Jim, since the wall will be covered I suppose it won't
matter about scratching the bricks with an abrasive.It's just it makes
a lot of mess and the garage is not empty. if it were empty, then that
would be a different matter.
Perhaps I'll try to skim the top layers of with a quick sand and over
paint what's left. What's best to us: a flap disc, a wire brush, I
wonder whether a sander would be adequate?
Thanks again.
Spamlet
"Fred" <fr...@no-email.here.invalid> wrote in message
news:uf8v76phoq8uttaj9...@4ax.com...
Can't see why you can't over paint: it's only a garage after all.
On the other hand, as it is a garage, if you did want to get the paint off,
it is one place where you could slap on caustic soda or caustic soda based
strippers, and hose down. Getting paint off masonry is never easy - but
easier outdoors than in! (People who put gloss paint straight on to plaster
are swine!)
S
The Medway Handyman
>
> I see you can get sand blaster attachments for pressure washers. Are
> they any good? But aren't we back to where we began that any abrasive
> will scratch the brick?
They are spot cleaning tools. Doing an entire wall would take ages & fill
the garage with damp sand :-)
--
Dave - The Medway Handyman
www.medwayhandyman.co.uk
stuart noble
it, but might well soak into the brickwork and create a new headache.
If the surface is clean and reasonably sound, I'd be inclined to leave
well alone. Maybe a quick going over with a wire brush to remove loose
stuff, but abrasion probably isn't going to significantly improve the
chances of the bitumen bonding to it. The danger is always that it will
pull the old paint off, but that is usually obvious during the application
Jim K
> On Thu, 02 Sep 2010 15:14:02 +0100, stuart noble
>
> >You probably can, but no manufacturer is going to tell you that. Suck it
> >and see on a small area
>
> Hi. I have had since another email from a different manufacturer of
> bitumen paint; this manufacturer has said you can over paint, so now I
> don't know who to believe! I think your suggestion of trying a small
> area is the only way to see.
>
> In reply to Jim, since the wall will be covered I suppose it won't
> matter about scratching the bricks with an abrasive.It's just it makes
> a lot of mess and the garage is not empty. if it were empty, then that
> would be a different matter.
dustsheets?
> Perhaps I'll try to skim the top layers of with a quick sand and over
> paint what's left. What's best to us: a flap disc, a wire brush, I
> wonder whether a sander would be adequate?
for just this purpose I've used one of these in an angle grinder
http://www.toolstation.com/shop/p35654
(says in 230mm grinder? but I've used em fine in a 4" angle grinder)
- let it have a go all over
- any obviously loose stuff will fly off no bother with little
pressure from you
- if bits stay put leave em on and paint over
- steady away.....
Jim K
Phil L
I can't understand why you are concerned about scratching the bricks when
you intend to slop bitumen all over them.
--
Phil L
RSRL Tipster Of The Year 2008
Jim K
echo
Fred
<stuart...@ntlworld.com> wrote:
>Maybe a quick going over with a wire brush to remove loose
>stuff
I was going to remove all flaky patches anyway.
> The danger is always that it will
>pull the old paint off, but that is usually obvious during the application
I think this is what the one manufacturer was afraid of.
Thanks.
Fred
<davi...@no-spam-blueyonder.co.uk> wrote:
>They are spot cleaning tools. Doing an entire wall would take ages & fill
>the garage with damp sand :-)
I might have tried on the external side of the wall but not the
inside. I just wondered what they were like generally?
Tabby
The only downside of not stripping it first is that the underlying
paint might peel off one day. Since its not going to come off easily
I'd almost certainly overpaint.
NT
Fred
<jk98...@googlemail.com> wrote:
>for just this purpose I've used one of these in an angle grinder
>
>http://www.toolstation.com/shop/p35654
>
>(says in 230mm grinder? but I've used em fine in a 4" angle grinder)
How strange. They sell this 75mm one for 4" grinders:
http://www.toolstation.com/shop/Power+Tool+Accessories/Wire+Abrasives/Wire+Crimped+Cup+75+mm/d80/sd1920/p68932
yet they sell the one you quoted, which is also 75mm, but state it
must be used in a big grinder. The wires in yours seem much more
substantial, do they think a small grinder would not have the power to
spin it? A big grinder will be heavy though.
Re. yours and Phil's question about why I was worried about grinding,
I did a google and found a number of postings on web sites and forums
advising against scratching bricks because it damaged the glaze. I
read these out of context: these were posts about removing paint from
external walls where the final appearance would have been important. I
suppose I was also unsure whether this was a purely cosmetic issue.
You are quite right that these walls will be covered and so I can
proceed this way.
I haven't got a wire cup (yet) but I do have a flap disc. I had
another go at it this evening and am making progress.
Thanks again.
Spamlet
"stuart noble" <stuart...@ntlworld.com> wrote in message
news:7DSfo.7800$os5....@newsfe18.ams2...
Er no: we covered all this quite recently in a long thread on paint
stripping, and the main problem with caustic is how to keep it in contact
with the paint for long enough. 'High tech' strippers have thickeners and
form a protective skin to keep the caustic in contact with the paint for
periods up to a week. Then paint and stripper can often be peeled off in
one sheet leaving clean masonry beneath.
There may be some caustic sensitive materials in modern walls for all I
know, but with traditional materials, acids are the problem: not alkalis.
Sodium hydroxide simply turns into sodium carbonate and washes out, on
exposure to air.
If the paint is water based and still stuck, the OP does not have a damp
problem in his garage after all.
S
Spamlet
"Fred" <fr...@no-email.here.invalid> wrote in message
In my experience, a wire cup will just cover your wall with grey metal
deposits that will look horrible and then go rusty. The 'brush' should
match the material to be brushed as much as poss - steel for steel, brass
for brass etc. Your flapwheel is probably nearer the mark, but really, as
others have said, you are just making unnecessary work for yourself.
Personally I wouldn't even bother with the bitumen. Limewash will be
brighter, and can be topped up as often as you like.
S
stuart noble
>>
>> If the surface is clean and reasonably sound, I'd be inclined to leave
>> well alone. Maybe a quick going over with a wire brush to remove loose
>> stuff, but abrasion probably isn't going to significantly improve the
>> chances of the bitumen bonding to it. The danger is always that it will
>> pull the old paint off, but that is usually obvious during the application
>
> Er no: we covered all this quite recently in a long thread on paint
> stripping, and the main problem with caustic is how to keep it in contact
> with the paint for long enough. 'High tech' strippers have thickeners and
> form a protective skin to keep the caustic in contact with the paint for
> periods up to a week. Then paint and stripper can often be peeled off in
> one sheet leaving clean masonry beneath.
So the blurb says but, in practice, there is no way to keep caustic on a
vertical surface, whatever thickener is used. If it dissolves the first
layer of paint, it then slides downwards. The real point here is that
caustic only works on oil based paints, so there is no point using it on
the typical masonry paint or emulsion.
>
> There may be some caustic sensitive materials in modern walls for all I
> know, but with traditional materials, acids are the problem: not alkalis.
> Sodium hydroxide simply turns into sodium carbonate and washes out, on
> exposure to air.
But both are penetrative and hygroscopic. Not something I'd want in my
bricks
Fred
<spam.m...@invalid.invalid> wrote:
> Your flapwheel is probably nearer the mark, but really, as
>others have said, you are just making unnecessary work for yourself.
I wasn't making work for myself, I was hoping to over paint, it was
the manufacturer that wanted to make more work for me! ;)
I did remove some more with the flap disc last night, until that wore
out. I did find that it wasn't making as much dust, so perhaps I was
learning to hold it better or apply the right amount of pressure the
more I used it? It seems I could have saved myself the work but as
it's 3/4 done, I may as well finish the last bit. Thanks.
Fred
<spam.m...@invalid.invalid> wrote:
>If the paint is water based and still stuck, the OP does not have a damp
>problem in his garage after all.
I don't know what the paint is but I guess it is either masonry or
emulsion, so I think both are waster based aren't they? I don't think
I ever had a big damp problem: the dpm is at ground level so a couple
of bricks on the first course have peeling paint from where those
bricks must have got wet in the past. Perhaps it's not just the
sanding where I am making work for myself; perhaps I shouldn't be
painting too! I am hoping to line the walls next with celotex and the
advice here was to coat the walls with the bitumen first. If it turns
out to have been unnecessary at least I haven't wasted too much money,
I guess the paint is only about £30 to do the whole garage. Thanks.
Dave Liquorice
> I am hoping to line the walls next with celotex and the advice here was
> to coat the walls with the bitumen first.
Seems a bit odd to have a damp proof coating on the coldside of the
insulation. With the celotex aren't you going to end up with a void
with damp proof on both sides thus capturing any damp...
Warm air holds more moisture than cold and the inside of the garage
will, generally, be warmer than outside and this warm relatively
moist air will make it's way into the void(*) and if not actually
condense raise the RH in there.
(*) Unless you foil tape all the joins etc as one would normally do
with celotex etc.
--
Cheers
Dave.
chris...@removebundy.co.uk
I dont have a genuine Dremel, my lookalike ( Aldi powercraft ) has
collet sizes of 3.2mm and 2.4mm and I want to make sure of a fit
before I purchase.
Chris