Does anyone know how best to remove tar from flagstones? Have tried a stripper, but it leaves a stain on the surface. The flagstones are inside, so a power washer is not an option!
Depending on what the flags are cut from? stone I guess you could try diluting the tar with thinners, this will probably have the effect of making it bigger, but will remove it eventually, alternatively try Fullers earth made in to a paste with white spirit, applied over the stain, then using some brown paper and an old iron, iron over the stain. Do this after a good period of time has elapsed, say over night, the spirit will soften the tar, and the Fullers earth will draw it up, provided it is a very thick paste, the ironing will further soften the tar and allow it to drawn into the earth. Let us know how you get on.
IF tar is dry and not wet and sticky, you could try using a needle gun, they are available to hire from most tool hire centres. Careful use is advised to avoid marking face of flagstones though. Hope this helps.
Thanks, I'm going to try the poultice and see how I get on. I'm a bit concerned about using a neddle gun in case the stone is marked, and have tried sandblasting before and the dust was horrendous. It can also remove the silicates in the surface of the stone and over time the flags delaminate.
One last thourght Oldhouse, contact SPAB. http://www.spab.org.uk/ If these dont know, then nobody will!