problem: making a barrel cam in Solidworks,

Hello everyone, I'm working on a project which is a cam profile design.
for making barrel cam I have 2 pairs of 3d spline, each pair make a 3d plain as a support for the follower.
The problem is when I'm trying to make a plain between this splines a deviation about 1 degree will be added, In other words Solidworks make a small slope in plains which make it impossible for CNC machine to create the part
if further information is needed I can provide it to you

Edu ​​​​​​​SOLIDWORKS ​​​​​​​