Removing broken fencepost

[Bill Wright]

A much safer idea would be to use high explosives.

Bill

[stuart noble]

I've always managed to get the old stump out. Not easy, but neither is removing (and disposing of) great lumps of concrete

[Andrew Gabriel]

I've done this a number of times. You simply use the stump in the concrete as a giant rawl plug. You can get Metpost repair spurs which are specifically designed for hammering in to this (a collar which wedges between the stump sides and and the concrete hole sides), but the ones designed to hammer into the ground work too, but may need shortening.

Ideally, the post should position in the socket so it doesn't quite touch the ground. That way, it won't rot.

The sockets with a clamping nut will grip the post better than one where you just hammer the post into the top with a wedge fit, and you can tighten them up if the post becomes loose.

BTW, if it's not really concrete but just a bag of postcrete, I rather doubt this will work as it won't be strong enough.

[Cursitor Doom]

That is the most exceptionally inaccurate/error-riddled explanation of how acids work I think I've ever seen. The rest of your post was more constructive, though!

[Cursitor Doom]

Exactly. There seems to be some "lack of awareness" here as to the capability of the oxidizing agent I suggested. I am talking about stuff like Rothenberger Toilet and Drain Unblocker which is approaching 99% pure sulphuric acid. "Concentrated" acids are typically only about 70% pure IIRC so it's very misleading. You pour "concentrated" acid onto wood and it'll probably only change colour. Pour on pure (or close to pure) acid and the results are totally different. You get instant charring, burning, smoking and spitting as the wood is destroyed. Any organic matter in fact will be attacked in this way, including human flesh. It really is like something out of an old horror movie. I'm quite astonished anyone can actually buy this stuff from places like BnQ in this day and age, but who am I to complain?

[stuart noble]

You can even have it sent through the post