Michel...
The extension is from MLCS.
www.mlcswoodworking.com There is a model that holds 1/4" bits and a model that holds 1/2" bits. Both models are to be used in a 1/2" router. They extend the bit about 2". Cost $35 They are, or were, on sale for $25.
They also sell carbide spiral upcut bits. They have a 1/2" diameter, 3" long, 1-1/2" cutting length for $35.
I'd be very interested in how the router approach works for you.
Joel
