Hi guys - I wanted to share an experience I had this morning with my new friend derickh. He came by to collect his wheel this morning after asking me to do the Bühler motor install for him. So I stayed up most of the night working on another motor block that I promised to send out this morning - and while I had derick's wheel already done I decided to give him a nice upgrade since he was letting me borrow his Oculus Rift. I decided at like 4 or 5 a.m. to switch his old style single fan "V16" circuit board for my spare new style "V18" PCB as a free upgrade. Anyways, I switched the boards out and switched the motor wires around (they are opposite polarity between the older wheels and newer ones). Then I fired up the wheel and made sure it went through calibration. So far so good. Time to get 2-3 hours of sleep.
So derick is knocking on the door at 10a.m. - our agreed upon meeting time, and wakes me up.
So I get up and get everything setup and ready - deciding to set up his wheel so he can try it out before he goes. And so I hit the power button, the wheel goes through calibration, and
all of a sudden there's a nice zapping sound and magic smoke comes out of the wheel!! Oh no!
So I unplugged the wheel
(so embarrassed) and started surgery. Turns out you shouldn't work on wheels when you've been up all night, lol. I had gotten lazy as it was late and I was super tired and when I removed the MOSFET heatsink I had just put a little more thermal compound on instead of cleaning everything up good first, and it overflowed the top surface enough to short one of the drive MOSFET pins. It must have worked for that super short duration the night before but been on the verge of zapping, then maybe flowed a bit closer to the pin after sitting upright all night and in the a.m. ZAP!
So derick had to sit patiently while I went through troubleshooting and repairing his wheel - which he was very good about - and I tried to give some pointers and explanation along the way so he wasn't bored. We desoldered the damaged drive MOSFET and a few other nearby components on accident because of the airflow of the hot air gun blowing them a bit and swapped the damaged MOSFET for a spare good part then resoldered the couple tiny ones that came loose due to the hot air. I made real sure to clean up the board good this time! After that we fired it up and raced for a couple hours with no issues, and boy is that Oculus Rift neat!
Just goes to show you that just because some magic smoke gets out it doesn't mean it's the end of the world. I keep a nice little supply of spares for the boards around just in case something like this happens - but this is the very first time I've had to use them. I'm still dope slapping myself for not cleaning that dang compound off last night.🤬