so i finally got around to building a proper dipole instead of just buying one. been putting this off forever honestly. used 14 gauge stranded copper wire i had leftover from some electrical work, cut it to length for 40m using the 468/f formula which gave me something like 66.5 feet total. the balun is just a choke i wound myself, 8 turns of RG-8X through a FT240-43 toroid i had in the junk box.

anyway my question is about the center insulator. right now i just drilled two holes in a piece of PVC pipe cap and ran the wire through with some silicone around it. it works but it feels kinda janky and im worried about water intrusion over time especially since this thing is going up and staying up. does anyone make their own or do most people just buy the plastic egg insulators or whatever. also wondering if the PVC is gonna get brittle in UV after a while.

SWR is coming in around 1.4:1 at the low end of 40 which im pretty happy with for a first attempt. gonna try to get it up higher than the current 25 feet if i can talk my neighbor into letting me use his tree.

yeah PVC will degrade in UV, not immediately but after a year or two outside you'll start seeing it get chalky and brittle especially if you're in a sunny climate. the egg insulators are cheap enough that its probably not worth messing around with — you can get a bag of them for a few bucks and they last forever. that said a lot of guys use those plastic cutting boards from the dollar store, HDPE is what they're usually made of and it holds up really well outdoors. i've cut my own center pieces from that stuff and they work great, drill a hole in each end for the wire and one in the middle for the feedpoint connection.

your 1.4 SWR on 40 is fine, most tuners will handle that no problem and even without one most modern rigs wont complain. if you want to trim it down a bit try pulling from the ends a few inches at a time and rechecking. also 25 feet is usable but yeah get it higher if you can, even 35-40 feet makes a noticeable difference on 40m.

the cutting board tip is legit, i think i read about that on eham years ago and have been using that method ever since. mine has been up in the midwest weather for going on 4 years now and still looks basically new. i do coat everything in self-amalgamating tape at the feedpoint connection which probably helps keep water out too.

one thing i'll throw in — if you ever decide to build a vertical next, the math is a little different and the ground radials are kind of a pain to deal with but the results can be worth it on the lower bands. i have a homebrew 160m vertical that beats my dipole by a decent margin on the low angle stuff, which makes sense given the geometry. anyway good luck with the tree negotiation lol