4-Axis Lead/Lag Perpendicular problem

Hi all,

I have Mincer Screw as I shown in picture1. I tried to machine using Isoparametric Machining with 4-Axis lead/lag for Tool Axis. Catia created tool path , but this tool path is not exactly what ı looking for. its not perpendicular to the surface. In 2nd picture I shown what I looking for and what I get , any advice for this ? 

I solve problem just use Multi-Axis Curve Machining and select guide with contact , for guide select helix