Thermal mod: safe drilling strategy for sealed pocket router enclosur - Page 1
Forum section: electronics / beginners

author: Xolin
author_rank: Newbie
timestamp: October 14, 2025, 04:43:41 am
content: I am planning an active cooling mod for my ZTE F50 5G router, which overheats significantly under load due to its fully sealed plastic case. The goal is to drill intake holes (bottom) and exhaust holes (top, for an 80mm fan).My primary concern is electronic safety during drilling, as the PCB is likely very close to the internal surface of the thin plastic case (~1mm to 2mm thick).I plan to use a Pin Vise (manual hand drill) for maximum control.My questions are highly focused on safety and execution:1. Drilling Safety: What are the best methods (other than visual caution) to ensure the 3mm to 4mm drill bit penetrates the plastic but does NOT scratch or damage the PCB tracks/components directly beneath?2. Antenna Risk: Since 5G/WiFi antennas are usually on the perimeter, is drilling small holes in the center of the top and bottom panels generally considered safe from an antenna damage perspective?3. Optimal Airflow: Is the top Exhaust configuration the undisputed best choice for a single fan in this sealed-to-vented configuration?For reference on the internal layout/PCB proximity, here is a disassembly video of the F50:https://youtu.be/Fy4PpXumxIM?si=UQZfQKRZ7uW30fRUAny expert advice on safe DIY drilling for sensitive electronics would be greatly appreciated.Thank you!

author: 5U4GB
author_rank: Super Contributor
timestamp: October 14, 2025, 05:04:45 am
content: Trying to get more info here, how is the case sealed? Is it welded PVC/ABS/whatever? If it's not a permanent seal, can you crack it open with a spudger to find the best locations for ventilation? For example if you do find a safe location to drill/cut it won't help much of there's a wall of FR4 sitting above it.

author: Xolin
author_rank: Newbie
timestamp: October 14, 2025, 08:01:41 am
content: Thanks for the feedback.The video I attached already shows how the case is sealed and the process of opening it, but I still agree that opening it is necessary to check for internal obstructions:https://youtu.be/Fy4PpXumxIM?si=nJMcsk6iNli5yk47I accept the advice and will indeed fully disassemble the router and remove the PCB before any cutting or drilling. This step will eliminate the risk of damaging components and allow me to take accurate measurements.

author: 5U4GB
author_rank: Super Contributor
timestamp: October 14, 2025, 08:24:08 am
content: In that case another thing you can do, if you've got a thermal camera, or with a bit less accuracy a thermal sensor, is check whether most of the heat is being generated in one spot, then cut a hole in the case to match a finned heatsink and thermal-epoxy it onto whatever the heat source is so the fins protrude outside the case. 40mm Northbridge heatsinks are ideal for this. I've done this before when there's a single major heat source, it carries the heat outside the case without relying on air flow through what looks like a very cramped layout.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: October 15, 2025, 01:10:13 pm
content: Good Morning Xolin, I wouldn't think it should get so hot, but I see in reviews that it does. The specs say it draws 2 amps, which is quite a bit, so I agree with the others that you should open it up to see what is generating the heat. Maybe just some ventilation holes would be enough, as adding the load of a fan would prove too much for the power supply. I see several videos on the net, so it seems to be popular. Good luck opening it up, and don't forget to come back here and let us know of your experience, whether good or bad.

author: jpanhalt
author_rank: Super Contributor
timestamp: October 15, 2025, 01:37:06 pm
content: The safest way to make holes with negligible push through is with a milling machine and center cutting, end mill. You can get down to translucency, then pick out the plastic disks. That also helps avoid getting chips inside the case. Since it's plastic, "hogging in " of conventional drills will be a problem. A mill will mitigate that problem.Most 2-flute cutters are center cutting. With a 4-flute cutter, you need to ask. If you are stuck with drilling, you can get drills for plastic that will not hog in so easily. An alternative I use is to dub off the cutting edge so you get a scraping action.

author: amyk
author_rank: Super Contributor
timestamp: October 15, 2025, 07:23:41 pm
content: I'd definitely disassemble it completely first, it's much easier to drill if you don't have to worry about what's on the other side.In the case that that's not possible, you can use a drill-stop clamped to the bit.(Is it just me or does the OP look heavily AI-generated? It's not how one would normally write here.)

author: wraper
author_rank: Unknown
timestamp: October 15, 2025, 07:33:00 pm
content: This won't work. It's akin of drilling holes in a smartphone. And even if you succeed drilling them with no damage to electronics, air won't go though it anyway. In best case some air could be pushed by slim laptop fan from one edge to another along the circuit board. EDIT, you cannot do even that as there are antennas all around. The best you can do is cut a hole in a housing and attach a heatsink onto the shields on PCB. If the device is just heating a lot but not malfunctioning when hot, just forget about modifications.

author: Analog Kid
author_rank: Super Contributor
timestamp: October 17, 2025 07:18:15 am
content: Quote from: amyk on October 15, 2025, 07:23:41 pmMight just be you. They made some mistakes, like their use of Odd Capitalization (the kind of stuff Trump does all the time):Quote"AI" probably wouldn't make those boo-boos. So I'm willing to give them a pass on being human.

author: nali
author_rank: Frequent Contributor
timestamp: October 17, 2025 08:41:06 am
content: Well GPTzero gives it 100% and Quillbot 75% probability of being AI.Looks like a duck, quacks like a duck...?