The Lapping Process

Out kit included the small piece of glass to provide a perfectly flat surface to do the sanding on. The process sounded quite simple: take the piece of glass, drop a few drips of water to hold the paper steady, place the sandpaper on top, put the heatsink on top of the paper and movie it in varying motions.

Just keep on lapping, and lapping, and lapping.

Things started off with the edges of the base becoming very smooth first, and gradually going inward with time. Unfortunately, the very center of the base still had a somewhat rough texture that was visable by the time we had used up the piece of 600 grit. Wanting to do things correctly, I went to the local hardware store and purchased another piece of 600 grit to make the base uniform (As a side note, 600 grit was the highest Ace Hardware carried. So, if you're thinking of buying all your own sandpaper it may be harder to find it then you would expect.). This piece helped, but after a good half hour the center of the base was still not as smooth as the rest. I decided that this was already taking long enough, and would continue on with the higher grits even though the center was not quite perfect. Keep in mind that it was still a drastic improvement over how the heatsink originally was. We do feel the supplies included in the kit are quite enough for the average lapping, but you may need an extra piece if you have a severe case.

You can still see the center isn't quite perfect, and doesn't reflect as well as the rest of the heatsink. However, it's still a huge improvement.

Going on to the higher grits things became much easier and took much less time. By the 2000 grit paper the base had already become very mirror-like (except in the center, where the slight roughness still occured. After the 2000 grit, I rinsed the heatsink well for the final time and placed it in the sun to dry. Thirty minutes later, I pulled out the dremel, the 10,000 grit polishing compound, and the correct soft attachment for the dremel. The polishing process was easy, although much of the compound was just thrown off the dremel (Okay, maybe the attachment I used wasn't perfect for the job, but it did it none the less).