Cleaning plaster off a carpet

[Lobster]

Oh God....

Despite having encased the entire hall and landing in h/d twill dustsheets, the plasterer who's just finished skimming the bedroom has at some point managed to bypass the dustsheet on the landing and deposited a 2"x1"x0.2" blob of multifinish directly onto the newish carpet, where it has now dried roughly to the consistency of granite and is stuck like shit to the proverbial blanket.

How the hell do I get this off then? Is there something which will dissolve it but not the carpet (or the colour therein?) I've thumped it a bit to break up the lump, but virtually all the plaster is still bonded to the carpet, just in hundreds of fragments.

I did some googling and was pleased to see my keyword "plaster" come up in NT's "cleaning FAQ" on uk.d-i-y - however when I expanded the link I discovered that the reccommended treatment was actually a rotary wire brush. So maybe I'll pass on that...

Help! David

[The3rd Earl Of Derby]

best you can do is keep breaking it up with a pin hammer till its becomes just hooverable dust then a carpet shampoo over.

[The Medway Handyman]

I would have thought a stiff brush (not brass) would do the job, along with some el bow grease. Plaster should go soggy when wet, so maybe a carpet cleaning machine? Failing that a mild acid should disolve it.

If its a newish carpet I guess you have some offcuts knocking around? Try stuff out on a spare piece first.

[The3rd Earl Of Derby]

Whats a mild acid? bearing in mind the stuff will bleach the carpet.

[Andrew Gabriel]

Something that doesn't dissolve the carpet. I have used kettle descaller to clean plaster splashes off stonework (what I had to hand at the time), but the OP will need to test a sample of carpet first. If the carpet has any plastic in the mix and you are using descaler, make sure it's suitable for plastic kettles or it will make the plastic strands brittle. The acid will need neutralising afterwards to prevent it continuing to slowly destroy the carpet after drying out, which can be done with Sodium Bicarbonate solution. Then you'll need to wash the Sodium Bicarbonate out.

[Owain]

You don't. Anything you do might make it worse and negate your claim against the plasterer.

The plasterer dropped it, it's up to him to sort it out. As it's newish carpet, it's not unreasonable to expect his insurer to pick up the tab for a new carpet if he can't come up with some trade secret for getting rid of it.

Actually, if it hasn't sunk/got trodden in and it's fairly dense pile carpet, you might be able to cut the lump out without damaging too much of the pile.

Owain

[The3rd Earl Of Derby]

To be honest all this chemical jargon and this 'n' that is not called for,had a few dollops of plaster on my carpet here an there when I've been plastering and I've let it set befor smashing it up into fine dust,hoovered it then got some fairy washing up liquid and dampened the affected area waited ten minutes then got the vax on it. Only problem was I had to vax all the carpet after the drying out process because the affected area look cleaner and newer.

[The Medway Handyman]

One with a pH of 2 or more. Acids do no bleach. Bleaches bleach.

Acrylics, polypropylenes & polyesters have good resistance to mild acids, nylon doesnt. Wool will withstand mild acids quite well.

Depends on what the carpet fibre is, that's why I suggested a trial on an offcut.

[meow2222]

First thing I'd do is sit the hoover nozzle by the lump and keep squashing it in pliers, each squash will break some more free and it'll be sucked up. Just keep going.

Which link took you to a rotary wire brush to remove plaster from carpet? I get the feeling this is not what was recommended.

NT

[Mark]

Ive done this more time then I care to admit ; Don't use anything wet or abrasives like wire brushes, just keep hitting it hard with a hammer and hover up the dust so you don't compress this in the carpet. When _all_ the plaster is gone and you are left with just a white stain then lightly wet and sponge dry two or three times.

-

[Lobster]

Souds a good first-line of attack: will have a go.

Oh, you feel right!

This was the posting I found: however when this link popped up on a google search (searched something like "carpet+plaster+cleaning", the two-line google summary of your post was all I saw, and it wasn't until I expanded the link that I found the advice therein wasn't exactly appropriate for my scenario!

David

[Stuart Noble]

Bloody hell. Just pick it off with your fingernail. If it's just plaster the whole lot will come off dry