[TowerTalk] Spacers for Open Wire Line

[Bud Hippisley]

AA4LR asked what to use as spacers for open wire line.  I used to buy the old ceramic spacers at hamfest flea markets whenever I could find them.  Unfortunately, I found that the weight of the resulting feedline was far too heavy for my installation circumstances  (since most of my open wire feedlines are in excess of 100 feet long and go to dipoles that don't have a center support).   Then I tried plastic coathangers, but couldn't find any that were strong enough to survive my drilling attempts. 

So three or four years ago I went to the nearest glass store and bought some six foot lengths of clear rods of (probably) Lexan (R), which I then cut at six-inch increments.  I'm not where I can measure the actual diameter I chose, but I'd guess it's maybe 3/8" or so.  (The six-foot long rods have a fair amount of flex but the six-inch spacers don't.)  I drilled a slightly over-sized hole close to each end for the copper feedline and after threading the spacers onto the two wires, epoxied the wires to each spacer.  Based on the past three or four years' results, I'd say my epoxying job was only fair, as some of the spacers have moved.  Alternatively, if you make the holes only slightly larger than the wire, once you have the spacers where you want them, you can give the feeder wire a slight "tweak" with a pair of pliers next to each spacer -- the spacers are then *very* hard to move!  

My original first choice was to cut a slot in each end of each spacer, drill a small hole inboard of each slot, and use magnet wire to anchor the spacers.  But I didn't have the time or the jigging to make slots that didn't chip off, and I've had problems getting the magnet wire to adequately grip the feeder wire in some prior creations, so I chose the epoxy route.

Bottom line for me -- these spacers are inexpensive, relatively easy to obtain raw stock for, and contribute only slightly to the total weight of the open wire line.

Bud, K2KIR




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