In Gadgets and Gizmos Part 8, http://www.youtube.com/watch?v=IEJVMRM1xaI - part of the video described this tool and the basic tool rest. It is not meant to replace 'conventional' tools but sometimes it can be useful for certain applications. Here it is shown in use for roughing a (incomplete) radius, as well as a groove, such as might be wanted for an "O" ring perhaps. Form tools usually do the job better but sometimes this approach can be another option. Watch my whole "Gadgets and Gizmos" series which begins with a very basic intro - http://www.youtube.com/watch?v=QeBU97uC-Yk - and then proceeds though several parts to gradually cover various things made in the past -- all usually to further small scale machining options on a tight budget.
