Removing fire cement residude from flue?

[Mr. Clueless]

I'll leave that as the thread title because that's the important one of the two.

I applied some fire cement to the flue joint as it had cracked. Wiped up where it had spilled, used water (didn't saturate, just dampened). All looked good.

Lit the fire & as everything dried out i saw runs over the flue. Not all over, but i'm not happy with it.

So it's not like it can be 'picked' off as it's just sort of residue.

Is there a trick to getting this removed??



Also, while i'm at it - same issue but this time cement residue. Not lumps of cement, just the staining that'll come from cement water but this time on paving slabs / bricks. Is there a way of removing that?
I'm not overly fussed about that one because it's a little out of the way & isn't terrible, but i thought i'd ask while i'm asking about the fire.

 

[Burnerman]

I just use one of those sponge wash ups on mine, with water.....takes a few goes maybe but there's no trace now.
How about a wire brush on the paving flags?
John

 

[Mr. Clueless]

I tried the wire brush on the paving but it didn't fare too well.

I was considering some acid solution but 1) wasn't sure if it was OTT and 2) didn't want to wreck the actual paviours.