*A big thank you goes out to PCTorque for hosting this amazing forum NBF.
Today, I decided to pratice lapping for the first time on my Thermalright HR-05 SLI heatsink. I checked it first with a razer to see how flat the base was and found it was convaved.
Items I used for this project are:- 400 grit sandpaper Walmart
- 800 grit sandpaper Walmart
- 2000 grit sandpaper Walmart
- 91% alcohol Walmart
- Masking Tape
- Thin piece of glass or marble
- Paper Towel and Q-tips
- 1 hr of free time

My lapping station, note I have the sandpaper in thin long sheets, you want to make long constant strokes, without adding pressure. You want the weight of the heatsink on the paper only.

The three types of sandpaper I'm using today. Some people suggest using 400,600,800,1000,1200,1500,2000 grit paper, but really isn't needed, because the paper will get smoother as you sand and it saved me alot of time this way.

Notice the base of the Thermalright HR-05 SLI heatsink is pretty shiny, but it has a rough nickel plating on top of the copper base. Lets get to work on removing the nickel and getting a smooth base of copper.

I used a sharpie to mark out the X, ok lets begin with the 400 grit

After about 20 mins with one sheet of the 400 grit paper, the base looks something like this. Notice the nickel is still around the middle? That is were it is convaved.

After another 25 mins with 800 grit

Finishing up with the 2000 grit you can see the shine and the middle of the base is raised from the edges, this will allow better contact to the chipset of the motherboard.
For this build, I'll be lapping the SB, NB, CPU heatsink, and the CPU waterblock. Cooling is very important to my build.
I hope you enjoyed my pratice run at lapping a heatsink