I needed to come up with a solution to adding water cooling to a outrunner motor mount.
I decided to use some 3.5mm aluminium tubing as it was a good size and a good conductor of heat. Only two tubes were used as the mount is small but more tubes could be added to larger mounts. 3mm aluminium was used for the packing in-between the tubes, being slightly smaller meant the tubes clamped nicely in place when the mount was assembled (see picture below).
Finally L shaped cooling fins were added to the back of the mounting to improve cooling.
The mount seems to be doing its job as my little motor is now running cool.