Thick wall or solid part of an otherwise medium-fill part I'm trying to design a camera handle, which will be around 8" long and will have a brass camera thread insert in the end, where the camera will be mounted.  (That way, I don't have to screw the camera thread into plastic which will wear out faster.)

If I print the handle normally, the end of the handle won't be solid so I can't solidly put that brass fitting in.  If I set the fill in Cura to 100%, the print will take a very long time and will be unnecessarily solid.  I only need a centimeter or two at the end to be solid.

Is there a way to get one particular wall in Cura to be very thick (1-2cm) without affecting the other walls?  Is there some other way to get a solid chunk in the end of the part?
I'd suggest creating a hollow tube with ~1 to 1.5&nbsp;mm walls. Then to increase the strength design your own internal structure rather than relying on the slicer to fill the part. This takes longer to model but you can design the strength of your part much better. 

Something like this 

If you were to then print this with 60&nbsp;% infill you'll have the strength and also use less material. If you happen to know specifically how your part would be loaded, you could then change the dimensions on that internal cross structure to take the loads better.