RE: is there a tool to cut slots for hinges?
GP slotter is the only way to go. I used it to hinge my 35% Edge. What would have been a day long job was finished in 30 min. BTW when building profiles I hinge half way through covering the covering process. I really like the Hangar 9 CA hinges the best for profiles. They have a slot in the center that really helps the glue to wick all the way through. I'll use Radio South hinges for pattern planes.
Adam Q