Very course sandpaper to take paint patterns off the walls

[sammy.se]

Hi All,

I hope this is the right forum to post this in:

A relative of mine (not me, I promise!) - in a moment of inspiration - decided to freehand decorate their newly plastered walls with flowers, using dabs of paint for the petals etc. Using all sorts of paint: Emulsion, gloss, basically - whatever they had to hand. This was 2 years ago, so it's well and truly dried now.

now, they've realised the error of their ways and want to paint over it. The problem is, the raised texture from the dabs of paint it showing through. I've used a powerful dewalt power sander on it, to smooth it down, but it's a very slow process. I'm using standard "B&Q" sandpaper, which isn't helping and gets clogged all the time. I'm sure I could achieve better results if I invested in some really course, specialist heavy duty sandpaper.

So, my question is - does anybody have any recommendations for a really heavy duty course sandpaper that will be effective on this task? A link to a specific product would be appreciated.

Thanks!!

 

[dc_ni]

Would something like this help:

http://www.axminster.co.uk/mirka-abrane ... 70-x-198mm

Here's the Mirka site which lists the types available:

http://www.mirka.com/en/Abrasives/Net_S ... ANET___540

 

[Phil Pascoe]

Hermes, Mirka, Bosch...there are many good ones - try a tool hire or a decent builders merchant rather than a shed, or buy on line.
You'll probably end up skimming over it. For every hard peak you manage to take off, you'll leave a trough somewhere else.

 

[henton49er]

Have you considered sandblasting?

 

[petermillard]

If you have something that can use it, then Festool Cristal is designed for sanding plaster - the abrasive bits are spread out over the surface of the paper to help prevent clogging - and is available from P40. If you need really aggressive sanding then Festool Saphir is good, available as coarse as P24.

As Phil.p says above, I'd expect to do a lot of filling, or have it skimmed afterwards.

HTH Pete

 

[Graham Orm]

Hot air gun if it's gloss?

By the time you've finished faffing you could have skimmed it, or got someone to do it for £60.

 

[petermillard]

By the time you've finished faffing you could have skimmed it, or got someone to do it for £60.

Not round here, you couldn't, lol!

 

[Mike.S]

I had a similar(ish) challenge when re-decorating - caused by the build up of gloss paint underneath a picture rail. Previous attempts at sanding (power and by hand) failed - the ridges always showed up under thick lining paper and emulsion. So, I used 'proper' paint stripper (supposedly for professionals nowadays but search the usual places and you shall find) - just two coats, each left for 10 mins then scraped off. Worked a treat. Grayorms hot airgun solution might also work, but I'd worry about cracking the plaster if used for too long in one place.

Incidentally, for other reasons I skimmed all walls in the room - used Toupret's Cachet Blanc (Decorators Skim Coat), sanded smooth using Mirka Abranet on Mirka's hand sander with shopvac attached. Worked a treat and got flat and smooth walls.

The Toupret is excellent stuff but pricey. I'd probably try one of the Gyproc skimcoat or filling plasters in future e.g. Easifill.

 

[carlb40]

Sand areas with 100g paper. Then use either a filler or patch plaster the areas, but cover a larger area than the paint to allow for feathering the edges. So lets say one area is 4 inch square, sand/fill an area of 18 inch square. That way you can keep the walls flat rather than have obvious bumps.

 

[Graham Orm]

Make sure you paint with PVA mixed 50/50 with water before putting any plaster on.

 

[novocaine]

http://www.screwfix.com/p/marshalltown- ... asp/74692#

then as is suggested fill in the holes and a bit around the surrounding area, light sand with sand paper at that point.

edit, whoops wrong link.

 

[Graham Orm]

I think he's done one

 

[sammy.se]

Thanks guys... all useful suggestions. It's mix of paint - gloass, emulsion etc, so i'll need to see if a heat gun would work on that (will take a while I imagine!).

I will try the Mirka abrasive and see how that goes - if it doesn't do the job, i think I'll recommned they go straight to skim!

Thanks for all the suggestions

Sammy