Best Chisel/tool to flatten concrete jutting out

[Israfel]

I'm about to tile my bathroom. One wall must have once had a Boiler and the hole for the vent has been concreted in. This concrete is jutting out and there's no hope of a flat surface to Tile onto. What's the best solution to smoothing down this concrete

 

[RedHerring2]

Can you post a picture? It might be a disc cutter will do the job sufficiently, or a hammer & chisel, depending on the amount and depth of concrete to be removed.
You might need both.

 

[^woody^]

Use a cold chisel

But a few blows with just a hammer will normally sort any protruding lumps out

 

[Prodigy]

Hello, are you sure it's concrete?!

I think you probably mean bonding, which does come in grey sometimes and so could be confused with concrete. Anyway, either way, you can't really "smooth it down" - unless it's only a small few mm protrudance, in which case an electric sander with P40 grade or lower should gradually do the job, you'll have to bash it out.

 

[Aqua]

The hole can't be large, therefore can you knock it out and rewall it so the finish is level/plumb?

If not and assuming it is concrete can you get hold of a Kango type breaker with a spade attachment which will be quicker and easier than a hammer and bolster.

 

[Israfel]

Hi all, thanks for the replys, the hole was large enough to be bricked in, it was the cement which was very roughly jutting out and what appears to have been a layer of polyfilla or one of those white cavity fillers generously dolloped on top. That was easy to get off, the ridges of cement I ended up cutting grooves in with an angle grinder and chiselling out. Not a professional job but it's flat enough to tile over now