[Chris McDowra (KI5HSQ)]

Finished the first truck node and figured I’d document the process for anyone else putting one of these together. Photos below track the build from rough start to finish.

The parts pile

Everything laid out before assembly: U.FL antenna pigtails, empty 2-cell 18650 holders in a few stages, and the fully-wired holder with battery leads and JST connectors attached.

Core components: RAK WisBlock (base + core), the N-type antenna and bulkhead connector, the printed enclosure back panel, the 20mm cooling fan, the KSD-01F thermal switch, and the wired 2-cell battery holder.

Dry-fit inside the enclosure: WisBlock mounted, batteries seated, antenna pigtail routed, USB cable staged for the solar connection.

Full electrical dry-fit with the solar panel connected via the barrel-to-ZH1.5mm pigtail, before final assembly and painting.

The bare white PETG enclosure back panel, straight off the printer, ready for sanding and paint prep.

Painted and clear-coated — red enamel over PETG, U-Pol UV-resistant clear on top.

Solar panel mounted to the finished red enclosure with the magnetic feet.

Finished Product

Final mounted result on the truck roof, antenna up, out in the field.

Bill of materials

Item	Link	Est. Price
RAKwireless WisBlock Meshtastic Starter Kit (RAK19007 base + RAK4631 core)	Amazon	$34.97
Omni Meshtastic 915MHz LoRa antenna, 5dBi, N-type	Amazon	$16.95
2x USB Solar Panel, 6W 5V	Amazon	$18.99
MEETOOT 40pcs 18650 Battery Holder (cases)	Amazon	$7.99
JST-PH 2.0mm 2-Pin connector pairs (20-pack)	Amazon	$8.99
JST-ZH 1.5mm 2-Pin connector pairs (10-pack)	Amazon	$7.89
uxcell M2.5 threaded inserts (50pcs)	Amazon	$6.39
M2.5 x 6mm flat head screws (50pcs)	Amazon	$5.69
XIITIA 20mm 5V DC fan (6-pack)	Amazon	$15.99
uxcell Normally Open Thermal Switch, KSD-01F 40°C	Amazon	$9.99
DIYMAG Rubber Coated Magnets (4-pack, for solar panel mount)	Amazon	$9.99
White PETG filament (Soleyin)		~$13.00
Rust-Oleum red enamel, filler primer, adhesion promoter, U-Pol UV clear coat, assorted sandpaper	AutoZone	~$80.00
	Total:	~$240.00

Estimated total: roughly $210–260, not counting the 3D printer itself or shop consumables (solder, wire, heat shrink) already on hand. But we are building more than one, so the price is lower per node.
(Per-unit costs on the multi-packs — battery holders, screws, connectors, fans — are stretched across more than one build, so actual per-node cost is somewhat lower than the sticker price on those line items suggests.)

Tools used

• Soldering iron (Butane doubles as a heat gun for the shrink tube)
• Micro Pliers
• Large and small Phillips head screwdrivers
• Hot glue gun
• Two-part epoxy (JB Weld — already had on hand, used to secure the battery holder to the bottom plate)

3D print files

1. 18650 battery holder: by Emigrand on Printables — Printables – 18650 Holder
2. Main enclosure: by Jesse Barlow on Printables — Printables – Mesh Car Node

Note that the main enclosure link is for the V2 and doesn’t include the fan or switch.

Notes from the build

• Printed the enclosure in PETG, not PLA — after some research on heat deflection temps for a sealed, roof-mounted enclosure in Texas summer, PLA’s ~56°C average softening point was too close for comfort. PETG’s ~80°C rating gives real margin.
• Watch your JST connector pitches — the RAK19007’s solar port (P1) uses ZH1.5mm, while the battery port (P2) uses the far more common PH2.0mm. Easy to order the wrong one if you’re not paying attention.
• Paint sequence that worked: sand (220, then 320–400 grit) → adhesion promoter → filler primer → red enamel (2 coats, within the 1-hour recoat window) → U-Pol UV-resistant clear coat (within 20 minutes of the final red coat).
• Fan + thermal switch is wired as its own independent circuit straight off the battery leads — not routed through the WisBlock — so it only draws power when the enclosure actually hits 40°C, which conveniently overlaps with peak solar production.
• Solar panel mounts to the roof via magnetic feet; antenna bracket is screwed down since it needed to be a permanent, low-loss N-type connection rather than a magnetic mount.

Happy to answer questions on any part of the build.

73

KI5HSQ

• This topic was modified 2 weeks, 2 days ago by Mike Spracklen.
• This topic was modified 2 weeks, 2 days ago by KI5HSQ.
• This topic was modified 2 weeks, 2 days ago by Mike Spracklen.
• This topic was modified 2 weeks, 2 days ago by Mike Spracklen.
• This topic was modified 2 weeks, 2 days ago by Phillip Beall. Reason: Updated to fix site induced formatting issues. - Phillip

[Phillip Beall (PHILLIPHAM)]

All,

OK, Chris’ post educated at least me, resident genius Mike Spracklen (K5ILO) explained it to me, but WP has a default that if a post has more than 10 links it has to be moderator approved. Seriously… I had no idea. That caused a lot of misery this evening. All fixed and OK, Chris, thank you VERY MUCH for your thorough debrief of what you did, how you did it and for the great pictures! Seriously, that is some great stuff!

73

Phillip Beall (W5EBC)

[Chris McDowra (KI5HSQ)]

Out in the wild.

[Phillip Beall (W5EBC)]

All,

Now that I finally figured out where Chris’ post had gone and got it properly published, I wanted to come back and add one more comment.

Chris, this is an exceptionally thorough build report. I especially appreciate the work you did looking at temperature limits for the various components. A sealed enclosure sitting on top of a vehicle in the Texas summer sun is a very different environment from something sitting on a workbench. Your decision to use PETG instead of PLA, along with the temperature-controlled fan, shows that you were thinking about the entire installation and not simply whether the electronics would work.

For anyone considering duplicating Chris’ setup, I would add one practical caution: before depending on magnetic feet, make sure the roof of your particular vehicle actually has enough steel content for the magnets to hold securely.

I learned that one the hard way. My personal Ford F-150 has an aluminum body. A while back I ordered some magnetic door panels for Tour de Paris, only to discover when they arrived that they would not stick to the doors of my truck. That was an entertaining way to learn the lesson.

So, before building around a magnetic mounting system, take a magnet out to the vehicle and test the actual mounting location. If magnets are not an option, I would look at suction-cup mounting feet or another removable mounting system that provides a secure attachment without requiring permanent holes in the roof.

That is exactly the kind of practical detail I hope we continue documenting as we experiment with Meshtastic installations. Chris has given anyone wanting to build a mobile solar node an excellent head start.

Great work, Chris. Thanks again for taking the time to document not just what you built, but why you made the choices you did.

73

Phillip Beall (W5EBC)

[Chris McDowra (KI5HSQ)]

HRCC has a similar build for an aluminum-body F-150 or a glass-topped roof. It’s the same type of print just uses suction cups instead of the magnetic feet. In his video, he does uses the slim, low-profile 3D print without the fan or switch.

HRCC – Truck Node

• This reply was modified 2 weeks ago by KI5HSQ.

[Chris McDowra (KI5HSQ)]

And the second one is painted and put together. This one went together in about half the time.

The full print time is about a day and a half with my Ender 3 Nero. Painting takes a full day to dry. Then putting it together is only about 30 minutes of work.

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