Trim parts from assembly

[ortho]

I have a cylinder assembled to a plate that is curved. I want to trim the cylinder so that it is flush with the curved plate, just as you would have it manufactured. I know it can be done but I can't figure it out for the life of me. Hope someone can help me out.

Thx

[robnew]

Edit the cylinder in the assembly , depending on how it was modelled extend it up to the plate surface i.e. if it was extruded then extrude it up to surface, which would be the curved plate.