Maybe I didnt understand what you are saying but carbon fiber for spacers will conduit elec depending how it is coated but I'm sure everyone know that.
Best Plastics, Composites, Rubber for structural antenna parts
Just a warning note about using ABS for structural parts that I've mentioned many times before - hopefully what you're planning to use is the thick walled stuff that has little or no flex. If you go to Rona or Lowe's or Home Depot and shake a 10 foot ABS pipe like a sword it flexes a lot. 
It seems to be rigid, but its not. If you shake a length of PVC like that it will seem like a wet noodle, so avoid using PVC for structural use either, except when recommended in build plans.
From experience I'm clarifying that ABS should never be used as a pole or mast, and it should be carefully considered if you're thinking of using it as a horizontal boom of any length more than a meter or a few feet.
It seems to be rigid, but its not. If you shake a length of PVC like that it will seem like a wet noodle, so avoid using PVC for structural use either, except when recommended in build plans.From experience I'm clarifying that ABS should never be used as a pole or mast, and it should be carefully considered if you're thinking of using it as a horizontal boom of any length more than a meter or a few feet.
