I was looking for variable capacitors for my home brew projects that do not have high costs.  I did a Google search and found the following links:

http://www.qsl.net/n4dfp/buildcaps.html

http://www.eham.net/articles/15975

The nice part is that you can make changes as you see fit.

I made some changes and modeled the design in SolidWorks.

From SolidWorks, I made a sheet layout in FabriWIN.  you can see spacer washers cut out of the “scrap”.

My .030″ aluminum rotors and stators only needed some deburring from the CNC turret punch press at work.  I also did not make the spring loaded rotational contact.  I just attached a ring terminal and some wire to the rotor shaft.  Below is a cap that I will be testing in a home brew antenna tuner.   I will increase the air gaps if I find it arcing.  I’m not sure that will happen at QRP levels. The knob is an old plastic gear from an old printer.  It prevents my fingers from changing the capacitance value.

73,

Mike (AB1YK)