26
Switched my mind about thermal paste after a 5 degree difference
I used to think any old thermal paste was fine for avionics boards. Last month I had a GPS receiver that kept throwing errors in the shop here in Phoenix. I cleaned off the old crusty stuff and put on a name brand paste I ordered from DigiKey. Dropped the core temp from 78 to 73 degrees Celsius after a 20 minute run. That 5 degree change stopped the intermittent lockouts completely. Now I actually measure the spread and don't just glob it on. Anyone else seen big swings from just swapping paste on flight hardware?
2 comments
Log in to join the discussion
Log In2 Comments
fionaa3519d ago
Oh man, that's wild! I read somewhere that on avionics boards the thermal paste can actually act like a tiny capacitor if it's the wrong kind, messing with signal noise. A 5 degree swing is huge for GPS lock reliability; those chips are super sensitive to heat creep. I saw a video where a guy tested different pastes on a drone flight controller and the cheap stuff actually had weird gaps after a few thermal cycles. Makes me wonder if your old paste was just cooked to a crisp from the Phoenix heat. Good call on measuring the spread, that's the part everyone forgets.
5
jennifersmith19d ago
That bit about the cheap paste having gaps after thermal cycles is exactly what I was thinking, it probably shrinks or separates over time. The Phoenix heat probably just accelerated that process, turning it into a crumbly mess instead of a smooth transfer layer.
6