Lapping dance

The lapping kit comes in a fairly uninteresting plastic bag which contains all the parts that’ll get your heatsink base reflective.

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You get a small tube of Arctic Silver Ceramique, a small pane of glass which acts as a flat surface, an instruction sheet and finally the varying grades of sandpaper.

The instruction sheet is simply a photocopied A4 page with different steps explaining how to get the job done. There are some amusing quotes such as, ‘Go slow and easy, don’t bear down too hard... …”Slow and easy” is better than “hard and fast”!’. Once your maturity returns, the sheet actually contains useful information that is beyond commonsense; keeping the instructions from sounding patronising.

Each different grade of sandpaper is a distinctive colour, meaning that even if there are no markings on the back (giving you the ‘P’ value) you’ll still know which grade to use. You start with a fairly abrasive P400 which is designed to remove any slight lumps (i.e. gets the base flat) and then you begin the shining process which uses a P600 sheet, then P800, P1000, 40 micron, 25 micron, 20 micron, 15 micron, and finally 10 micron.

According to the instructions, there are two ways of sanding the base. You can either go for flatness, or reflectivity. Depending on whether your heatsink base was flat in the first place will determine which path you choose. The difference is explained here in more detail. To get a flatter base, you have to use a circular or figure-of-eight sanding method, while getting a shiny base requires you to simply sand in a straight line.

The sheets of sandpaper are the same size as the glass pane, and will only give you one try to get this right. It’s a one use kit, although the pane of glass is arguably the most useful part, as the sand paper grades can be bought separately from a good DIY store. Either way, this is a good kit, with everything you need, to start your lapping career.