With Heat Sink and Pentium Cooling Fan
Here is how I tried to keep my regulator cool. I installed an extra plate of aluminum between the regulator and the frame, and attached it with silicone heat transfer paste. Then, attached the cooling fins and the fan on the outside.
The VFR regulator has the heat sink on the frame side of the regulator, so it's a toss up whether the regulator is dumping heat into the frame, or if the frame is heating the regulator. So I added the extra plate in an attempt to dump more heat into the atmosphere. Also the Fan heat sink only contacts the regulator on the outside edges, so not a lot of heat gets to the fan heat sink.
It didn't work. The regulator was already acting up, but this kept it alive for another few months. So it was better than nothing.
When it finally failed, I was caught short, and in order to keep going down the road, I replaced it with a regulator from a VF500.
The VF500 regulator is made just the opposite of the VFR. The heat sink is on the outside and the potting material is next to the frame. Also the VF regulator has cooling fins. So I mounted the fan on the cooling fins of the VF regulator.
The connector was salvaged from the original VFR750 regulator. As you can see the soldering at the connector is not pretty, but it works. The Idea was to replace the VF regulator as soon as possible, but it has worked so well, that I've decided to run the it until it fails.
When I do go back to the proper regulator, I
will invert it. Mounting it with the outside against the
frame, and a pentium fan and heat sink against the frame side of
the regulator, which is now the outside. That will minimize the
amount of heat that gets to the regulator from the frame, and
maximize the amount of heat that gets from the regulator to the
fan cooled heat sink.