Removing mortar

[Saifu]

I've got a stone wall 2.5ft high and 4m long to pull down and rebuild but I need to work with the existing chunks. They are 50mm concrete slabs broken up. Is there a quick way to remove the old mortar than using hammer and chisel? Reason I can't use fresh pieces are due to location. Garden without a side access. Wall is at bottom of terraced garden, 3/4 levels down from street.
Taking the old stuff out and bringing the new down would be backbreaking labour.

 

[Tigercubrider]

possibly an SDS drill and chisel

 

[^woody^]

A sharp 2" bolster chisel and lump hammer, and use it right at the joint between the slab and the mortar.

 

[Saifu]

Been using a 2" chisel and lump hammer. Apart from wearing down knuckles, chisel doesn't stay sharp for long. Its pretty blunt after doing 1m section. Also mortar doesn't always come off in one piece and there are places mortar is a mound with no leverage. Will take days to bust the mortar this way. Was hoping I could find some solution that would etch it off and I could then throw the pieces in a bucket of solvent.

 

[Saifu]

possibly an SDS drill and chisel

SDS drill sounds possible. Wonder if cheaper one for £60 would be effective or bits would just go blunt. Maybe tricky to hold drill and pieces of slab?

 

[^woody^]

Its pretty blunt after doing 1m section

You must have a cheap Chinese chisel then.

BTW, if this is so hard, why does the wall need to be rebuilt?

 

[Saifu]

You must have a cheap Chinese chisel then.

BTW, if this is so hard, why does the wall need to be rebuilt?

Chisel wasn't sharp to start with really. Amazon purchase. Around 70% good reviews. Assumed they don't design them to cut salad. It's a retaining wall leaning out on top, towards the last 2 or 3m with vertical cracks in two places. I dug out he soild behind the wall. I've rebuilt 1m2 section successfully on another terrace. Took me 2 days of 3hrs chisseling and mortaring each time. All the while thinking, I feeel sorry for stone masons!