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Tune Around! Topics For
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The N3HNA PVC TUBE MAST TOWER PROJECT by
Dan, N3HNA
20' PVC Ham Radio Mast/Tower Parts List: (See end of article for additional
information) Qty. Part Description 1 2" (diameter) 10 Foot Solid Core PVC Pipe - Schedule 40 1 3" (diameter) 10 Foot Solid Core PVC Pipe - Schedule 40 2 3" U-Bolts 1 PVC Reducer from 3" to 2" 1 PVC Glue 1 PVC Purple Primer 1 2" PVC End Cap 3 4" Galvanized or Stainless Steel Bolts with washers and nuts 2 1.5" x 5" Galvanized Backing Plates 1 NIBCO 1/2 inch Copper Adapter 1 NIBCO 1/2inch Copper Pressure Cup C x MNPT Adapter 2-3 Large 1/2 inch Galvanized Washers 3 2" Diameter Hose Clamps (Optional) 3 3" Diameter Hose Clamps (Optional)
The photo above includes: Copper Adapters NIBCO 1/2 inch Copper Adapter NIBCO 1/2 inch Copper Pressure Cup Adapter 2" PVC End Cap PVC Reducer 3" to 2" High speed internet connection required to view
videos below!
It is assumed that basic tools are available; electric drill (either hand drill or bench press), wrenches, screw drivers, pliers, etc. This project can be constructed by one person, however, it would be much easier and much more enjoyable with two or more people. 1. Coat one end of the 3" diameter, 10' long PVC pipe with PVC primer. Coat the inside of the 3" diameter PVC reducer (3" opening) with PVC glue. Attach parts. Let glue set up for a couple of minutes. 2. Coat one end of the 2" diameter, 10' long PVC pipe with PVC primer. Coat the inside of the 2" diameter PVC reducer (2" opening) with PVC Glue. Attach parts. Let glue set up for a couple minutes. (At this point both 10' long sections are attached with the PVC reducer in the center. The 20' long assembly is pretty tender at this point. Prop up the ends as well as center joint to reduce flexing. Or have the assembly on a level surface.) 3. Drill a hole through the 2" collar on the PVC reducer that goes completely through; or drill a hole on each side that provides a clear path for the bolt. The drill bit size should be matched to the bolt size. Run one of the 4" bolts through both holes, attach washer and nut. Tighten firmly but watch the flex of the PVC. Do not over-tighten to the point of severely bending or cracking the PVC. 4. Place backing plates over the 2" reducer lip/collar by approximately 1/2" and at the joint of the 2" PVC pipe and reducer. Mark holes and drill through. Tighten but do not over-tighten to the point of severely bending or cracking the PVC. At this point the assembly should be pretty rigid and strong. 5. Drill a 1/2 inch hole through the center of the 2" end cap. Spend extra time trying to make the hole as centered as possible through the end cap. A slight off-center hole will be more obvious with a long vertical antenna at the top. (At this point it is assumed that a copper antenna like the J Pole has been constructed per any of the online guides, or my video of a simple J-pole build. See below for more of my video projects including the J Pole.) 6. Solder the 1/2 inch copper adapter to the bottom of your copper antenna of choice. 7. Assemble the 2" end cap with washer, and 1/2 inch copper pressure cup mount on the inside of the end cap. Tighten. 8. Apply PVC primer to the open end of the 2" diameter 10' PVC pipe (this is at the top of the assembly). 9. Apply PVC glue to the inside of the 2' end cap. Attach end cap to 2" pipe. Let glue set for a couple minutes. The placement of the PVC mast is an individual choice. For my assembly I used two 12" long 2"x4" cuts to hold the lower section of the assembly off the corner of a greenhouse. I used the two 3" U-bolts to hold the lower assembly by simply drilling holes through the 2"x4" cuts and then screwing/bolting the two holding cuts into the corner of the greenhouse. I ran the coax feed line and grounding wire down the outside of the PVC assembly. A different option would be to run the coax feed line and grounding wire through the inside of the PVC assembly. If this option is chosen, two holes can be drilled at the top of the mast and then the wires simply run/pulled through. This PVC mast/tower has been surprisingly strong. It has survived 70+ mph winds with driving rain and debris. In time the PVC will degrade from UV exposure as well as exposure to large temperature extremes. However, several years of use for a very inexpensive project may make the effort worthwhile. The total cost for this build in July of 2012 was around $50. Your cost may be different! See more cool video projects, 46 in
all, by Dan, N3HNA on YouTube here! Download
a PDF copy of this article here! Check out his web site at http://www.dans-projects.com/Home_Page.php Good luck! 73 - Dan - N3HNA Additional info and ideas from John, HI3/KL7JR For my "brackets or backing plates" (I call them splice plates) I use either one or two lengths of 12 inch long aluminum angle secured with hose clamps to beef up the pvc reducer. For smaller dia PVC one angle is adequate but for heavier and longer runs of PVC pipe a length of angle goes on each side of the reducer and hosed clamped down. See drawing below.
Obviously aluminum angle is the
lightest available and easily strengthens the transition piece. The
aluminum angle will be lighter than using steel bars and bolts and
probably just as strong. 73
John |
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