In article .com,
"51" writes:
(Posted this early today but news server is not releasing it)

Hi all.
I will need to rake out the old mortar on my back yard walls.
What is the best power tool solution for this kind of job?

I would say that generally if it needs a power tool, it doesn't
need doing. There are exceptions (like where some clueless person
has pointed with pure cement, or a very strong mortar which has
shrunk and cracked).

I use a tool which looks like the front wheels from an old roller-
skate, with a handle and a replaceable nail which you set the depth
you want to rake out to.

--
Andrew Gabriel