The Brew Cabin

Hello!

I have just laid a patio with buff slabbs with a 10-12mm spacing that I was going to point.

I though it might be nice to include some red cement dye in the pointing. I mixed the dye and cement and sand as a dry mix and brushed it into the joints.

I then wet the mix and took a rounded tool along the top of the joints which helped bring out the dye. I also rinsed off any excess jointing at this point.

The trouble is that I now have a slight pinky tinge round the edge of some slabs where I had to brush the dry mixture in. Can anyone tell me how I might remove this pinky tinge.

Thanks.

Hi
If you have a digital camera post a photo of the worse bits.This is a job for either Oxalic acid,Muriatic acid or a phospheric acid depending on the severity of the stain.I`m sure Tony has posted info on these substances before -be very careful!

Also can you be a bit more specific on "buff slabs" what sort of stone? natural,or a comp.flagstone?

I don't think any of the acids will help very much, as it's the dye that has 'stained' the edges of the paving, and that colour comes from an Iron Oxide based product that is incredibly hard to shift - that's why it's used as a dye!

Cement dyes are not intended to be used 'dry' - they have to be mixed with a wet mortar, to fully disperse the dye and bring out the colour. Until the mortar is wetted, you've no idea just how 'strong' the colour will be. Further, water 'fixes' the dye into the cement content of the mortar. By using a dyed dry mix, the dye has been able to migrate and seep into the concrete of the flags. :(

A digipic would be handy, but when I've come across this issue in the past, it's been impossible to rectify. The worst case I've seen is the eejit in a village not too far from here (a builder, would you believe??), who decided to joint some buff block paving he'd laid with a mix of jointing sand, cement and black dye ....OH....MY....GAWD!! :o