I had some issues drilling the spreader, I thought the drill would go through the copper like butter, that is partially true, but as this is a very thick piece I’m drilling, it grabbed the drill and twisted it. I had two 2.5mm drills twist to bits and I could not get them out of the hole. This actually happened on the first hole I drilled, so I ended up moving the whole PC board 2mm to the side. Now I marked the MRF150′s and I think it’s very important to mark them first, drill and solder afterwards so there will be no forcing of the pcb when they are clamped tight. Unfortunatly I broke on drill in one of the mrf150′s mounting hole, but I could drill the hole and tap it. I hope I did not damage the tapping drill, as a bit of the old drill was wedged in the hole!. secondary plan was to widen this one hole to M4.
Here is a picture, this was surprisingly badly drilled – I blame not having a proper tool to mark with ;P
here is a picture of the “handywork” – put some lines over to see how it really went, it’s still withing tolerance and the mrf’s are clear of the PCB, and no forcing when taped down. I used M3 screws – and for that I think you have some room for “mistakes”
