Victor Burnouts

[Bob Ward]

Al,
I've unsoldered parts from a lot of non-USF boards, including packages like these FETs, but the solder seems very difficult to melt out on these. My always reliable heated solder sucker can't melt it. I put a larger 1/4" chisel point iron on all three pins and it took a while to melt. I guess the traces must be huge since these just pull the heat away. Parts of the board and the screw terminals get pretty hot. I seemed to lift a pad on one side or the other on just about all of them. Then I started snipping the FETs off and taking out pins one at a time. Still lifted pads. I guess you need a very hot iron. Since my sucker wouldn't work, I ended up using a PC board drill to clean the holes out. Of course, if they are plated through, I may have partly or completely removed that. I tried soldering in a new FET, but there wasn't anything for the solder to stick to on some pins.

I am sure if I play around longer I can get the knack, but I don't think I will. You are right about the stress probably shortening the life of the rest of the board. I will either have them rebuilt (I see http://www.rotordesign.com/victor.html is doing them for $75 now plus shipping) or we will just get new ones. The rebuilts will be good for practice and we'll save the new ones for competitions.

I guess we have a motor problem that is blowing them. We lost one Vic and the replacement also went. I wish the breakers 'broke' fast enough to protect the Vics. As someone mentioned, the Vics 'sacrifice' themselves to save the breakers. Well, for my sake, they don't have to be so selfless. I wish they would let the breakers do their job.

Since I have trashed this board, I will probably rip it apart and see what I find in the way of layers.

BTW, I have now 24 brand new (and one slightly soldered) IRL3103 FETs from Mouser that I probably will not be needing any more. I don't know if its legal to offer things for sale here so I won't do that, but if anyone wants to discuss FETs, let me know.
Bob