Which tool to route out a 30mm x 6mm slot in mortar?

[epsilonGreedy]

Rather than build up 6 block corners above dpc with appropriate fixing slots for my new Blake brick laying profiles, I want to mount them onto the existing below dpc blockwork. This will require creating two small slots per corner for the profile mounting tangs. The slots need to be 30mm x 6mm x 40mm deep to receive the profile mounting tangs.

 

The slots will be created between the blocks in strong mix mortar that has been set for 3 weeks.

 

I have read mixed reports online about how well a corded multi-tool will cope with this job. There is a total of 12 slots to route.

[Moonshine]

from your description of what is needed, could you not use a wall chaser? basically its two cutting discs side my side, used usually to chase out walls for electrics to run in.

 

https://www.screwfix.com/p/titan-ttb293wch-150mm-1700w-electric-wall-chaser-230-240v/80530

 

 

Edited July 1, 2019 by Moonshine

[Declan52]

A hammer and a cold chisel or if you have them metal line pins. 

Just remember that you need to rake them out when still wet for when you need to lift them. 

[Mr Punter]

Stitch drill with a masonry bit.

[Russell griffiths]

4inch grinder with a diamond blade. Wiggle it from side to side whilst plunging. 

Would take less than a minute per slot. 

Edited July 1, 2019 by Russell griffiths

[Onoff]

Would 8mm be too big?

 

https://www.ebay.co.uk/i/163663062981?