Replace Low Voltage Bi-Pin Halogens with LEDs

Step 5 Mount driver circuit

The next step is to wedge the wood scrap with driver circuit into the back legs of the heatsink. You may need to file, sand or carve some of the wood away to get it to fit. Be patient and don't cut any of the wires. Try to push it in until the prongs from the bi-pin driver are just barely extending beyond the back legs of the heatsink. You might also want to take some measurements or test fit the assy in your intended light fixture to ensure that it will fit and adjust your height accordingly. With that all squared away get out the glue gun and glue the block in place. Once this cools you can drill some holes in the side to add screws if you desire or just use as is. The heat sink may get warm enough under prolonged use that the glue softens, depending on your LEDs, the current used, and the glue formulation. This heatsink is rated for 10W dissipation and a 5 degree C per Watt temperature rise in still air. So since we are running the LEDs at 600mA, this is about 9W and we can expect the heat sink to get 45 degrees hotter than ambient at steady state without active cooling. That is pretty hot, so some screws might not be a bad idea. Or you can dial back the current by replacing the current set resistor on the driver board. I believe it is R1 on the board and is either 1.5 or 3.0 Ohms depending on which version you buy.