foam: how to remove from brickwork

[Fred]

Hi,

I discovered that when my carport was built, the builders left gaping holes where the joists entered the brickwork of the house. I decided to fill these holes with some foam. I bought the low expansion type because I know how much trouble foam can be ;)

Unfortunately even though I used the low expansion foam and even though I underfilled the holes to allow room for expansion, the foam expanded a lot and some dripped down the walls. It looks like an ill snail has crawled all over it!

The problem is that I have these bricks with a rough surface, IIRC they are called "rustic" bricks. I think they are a PITA because there rough surface is a magnet to get things like foam stuck in and its not very gentle on your knuckles either ;)

I tried very light sanding with a 240 grit paper and it removes some of the cured "trail" and I have tried scraping the grooves of the brick clean with a Stanley knife but it is a slow process!

I did try foam eater but I think that made it worse because rather than have to remove a narrow foam trail, I now have a broader foam eater trail to clear away ;(

I am thinking of using a wire brush. Would that work? I'll have to go and buy one, I threw my old one away. I suppose a powered wire brush on a drill would be too powerful and ruin the bricks?

I found that using a hole pipe blasted a little off. If I borrowed one of those 100bar jet things do you think that would work?

Thanks in advance.

[Andrew Gabriel]

Wire brush usually damages brick. Depending on the hardness of the brick, you either scratch the brickwork, or the metal rubs off the brush leaving a metalic finish on the bricks. You could try it in a hidden area.

[Tanner-'op]

Nip to the chemist and buy some acetone (or you can use nail varnish) and the may do the trick - (it doesn't always work on porous materiala).

[Cicero]

=================================== If the wire brush is too harsh or marks the bricks try using an old style floor scrubbing brush. They have strong bristles and they're dirt cheap at a hardware shop.

Cic.

[Steve Firth]

Most chemists will now suspect you of being a wannabee terrorist if you try to buy acetone. And you mean nail varnish remover, not nail varnish.

[John Stumbles]

I was going to suggest that (a pressure washer). I bought the LiDL one the other day and found that it even gets the fine roots of Ivy off rough brick walls.

[Tanner-'op]

Nice spotting Steve, the old finger pressed the send button before the brain was engaged (or signature typed) - and as for the "wannabee terrorist" suspect - well if you take a photograph of a badly parked police car now, you have a good chance of getting arrested under the Terrorism Act (it was done recently to a person who did just that).

Tanner-'op

[NOSPAMnet]

And where did the word "foam" escape to from the subject line . I now have three seperate threads for this one topic showing ....

[Steve Firth]

Outlook Express is a pile of steaming manure, and it assumes that everything before a colon should be removed from the subject line. Since Outhouse believes that the only text that could appear before ":" is Re, FW etc.

[Andrew Gabriel]

Oh, I've got some of that. Sounds like a good excuse to get the 1600W water pistol out of the garage...

[Tanner-'op]

No idea, I just clicked on "Reply Group" and did not edit the headers - as it is here.

Curious.

Tanner-'op

[TheOldFellow]

One saving grace is that over the next year or so Ultraviolet Light will degrade the exposed foam and make it easier to brush off. You'll need to brush if frequently after this process starts to expose more to the UV. Of course, this assumes that the wall gets some sunshine....

R.

[The Natural Philosopher]

acetone is available from most fiberglass suppliers. e.g.

[The Medway Handyman]

Would a brass bristle wire brush be better?

[Andrew Gabriel]

Brass will rub off onto the brick.

[The Medway Handyman]

Ah. OK, just wondered.

[Fred]

Thanks, I couldn't remember what they were called. I have borrowed my neighbour's; I'll let you know how I get on.

[Fred]

Thanks. I expected a wire brush spun by a drill would do more harm that good. I never knew that doing it by hand would leave a metallic film though. What a shame that brass is the same too.

What about these nylon drill attachments (as seen in the Toolstation catalogue). Would they be too harsh?

[AW]

replying to Steve Firth, AW wrote: pvc cleaner is acetone and readily available without risk of arrest

[The Natural Philosopher]

I made the same point 8 years ago, when this thread was active.

I think there is something essentially stupid about people who use homeowners hub. Well there has to be: That's why they use it.