Use PVC plastic for antenna builds?

Yeah, you’ve heard by now you can make anything out of PVC pipe. Youtube has a gammit of videos about it.

So you’ve also heard about using PVC pipe for home brew ham radio antennas? You bet. But beware that plumbing grade, white PVC pipe, unless you paint it, degrades, breaks down in ultraviolet sunlight.  All that effort to build your mast or rig only to have it fall apart in couple of year if that plastic is unprotected!

Note that the ‘grey’ color PVC pipe intended for electrical applications does not degrade as badly in outdoor applications.  It’s approved by the electrical code for this reason.  But it’s more expensive, and the grey PVC isn’t suitable unless it’s ‘Schedule 40’, thick PVC.  If you choose this option, go to an electrial supply house and buy it as they will stock the thicker walled grey PVC for your application.

Beware, however, that just painting plumbing grade, white PVC without prep could mean the paint flakes or peels away just months after painting it. This is not too disimilar to what happens with painting galvanized steel if not properly prepared prior to painting.

The instructions I’ve read about painting PVC plastic are TOO COMPLEX. Here it is simplified from a guy who does professional fabrication:

  1. You must prep the plastic surface if you plan for the protection to last as long as you intend for the antenna, or other PVC project to last outdoors.
  2. Prep means breaking down the glossy PVC surface, the “wax” surface of the PVC. Failure to do this is what makes your hardware store paint peel off.
  3. ‘Sand’ off the glossy surface using a 3M or similar abrasive pad. Don’t use finer grit sandpaper as it only gums up the sandpaper. At that point your sandpaper is useless.  The abrasive pad doesn’t clog up.  If the spot is still glossy, this is where it is likely to peel away.  This is the mechanical prep choice and requires arms that will not tire easily.
  4. Another prep choice is using ACETONE to break the wax surface of PVC. Problem – it’s super flammable!  Flash fire hazard.  I don’t recommend this choice unless you’re a pro and have fire suppression gear and proper ventillation.  Done improperly also means making the PVC material Gumby-like, loose like a pasta noodle.  This is chemical prep choice #1.
  5. Second chemical prep choice is choosing a paint with a solvent that will mildly attack the PVC plastic causing a super-bond and become part of the PVC.  The problem here is cost potential of the paint and availability of where to buy it at a hardware store.  Consider buying from a boat/marine supply house; just tell them you want paint for PVC plastic.