Heltec V4 Solar Tree Node - PVC Pipe Mast Version

This is the follow up to my Heltec V4 solar tree node. The original hangs from a rope and worked fine, but I wanted to get up above the canopy, so I redid the whole case to screw onto the top of a 1-1/2" PVC pipe. The pipe gets hoisted up on a rope over a limb, and a tag line on the bottom keeps it from spinning around and gives you a way to pull it back down when it hangs up in the branches.

Same guts as the original: Heltec V4, 3000mAh pack and 3 of the little 6V panels. The panels slide in from the top, the sled drops in from the top, and the cap goes on with 3 screws. The antenna hangs down inside of the pipe. There are still no seals on purpose. The electronics sit up high and there are weep holes below the panels so anything that gets in can drain back out.

The thread in the shell was sized to a Cantex 1-1/2" male terminal adapter (Cantex 5140107, Ace #33222). You glue the adapter onto the pipe and the node screws onto it. Mine threaded on nicely printed in ABS, but that was tuned on my printer with that adapter, so yours may run a little tighter or looser. The thread is a straight approximation of NPT so it snugs up instead of wedging like the real thing. 2 M3 screws through the collar lock it in place.

Rope options

Rope Guard is the one I'm running and the one I'd recommend. Use the drill jig to put a 3/8" hole through the pipe, clamp the 2 guards on, run your rope through and tie a normal knot. Print 2 of the same file.

Hoist Collar A and B are my first attempt. It clamps the rope in an S shaped groove so you don't need a knot, but it's fussy to get together and the rope guard is a lot easier. I left it in here in case somebody wants it.

Bottom end

The End Cap slides over the bottom of the pipe with 6 M3 screws. Drill the pipe with a 1/8" bit. The tag line goes through the center and the Clamp Puck halves bite down on it inside of the cap, so no knots to come undone.

Before you hoist it, pick it up by the rope point with the node on and make sure the bottom end drops. If the top wants to flop over, your rope point is too low. I'm running 2 10 ft sticks now with the rope about 9 ft down from the top.

BOM

1x Heltec WiFi LoRa 32 V4

1x Meshnology 3000mAh LiPo battery

3x 6V 1W mini solar panels, 110 x 60 mm (Flylin)

3x 1N5817 Schottky diodes, one per panel

1x 2-pin SH1.25 pigtail for the solar input

1x U.FL (IPEX) to SMA bulkhead pigtail

1x 915 MHz SMA whip antenna

1x Cantex 5140107 1-1/2" male terminal adapter

1-1/2" Sch 40 gray PVC conduit (sunlight resistant, avoid foam core)

PVC cement

5x M3 heat-set inserts

3x M3x10 screws for the cap

2x M3 screws for the collar

12x M3x16 socket head screws and 12x M3 hex nuts (end cap 6, puck 4, rope guard 2). Add 8 of each if you use the hoist collar

4mm paracord

Foam for the battery bay

Printing

I printed everything in ABS, no brim. ASA should be fine too. Everything is already oriented in the files. PLA won't last outside.

Shell and Sled: 5 walls, 25% gyroid, 6 top, 5 bottom. No supports except inside the 2 collar screw holes on the shell. I dropped the layer height to 0.12 through the thread.

Cap: 5 walls, 15% gyroid.

End Cap, Clamp Puck, Hoist Collar, Rope Guard: 6 walls, 30% gyroid, no supports. Turn on sacrificial layer bridging for the screw pockets (counterbore hole bridging in Bambu Studio).

STEP and Fusion files are included so feel free to change it and stuff whatever you want in there.