Lap that SLK!

I finally got around to lapping my SLK-800a and my temps under full load dropped to 36c! (with all fans on full power) Room temp is about 23c today.

If you haven't lapped yet, I'd highly recommend it!

The base on the one i got looked kind of grooved, i think some people could benefit from doing this. I have not tried lapping mine yet. I plan to do so.

It all depends on how bad the base is. I had to lap mine because I had ridges that were each 1mm deep.

Mine came with a mirror finish, no lapping here

Zoilo... 1mm deep? That's .039" deep. About the equivelant of 8 hairs deep.

And what was the temps BEFORE you lapped?
Rob

Load temps averaged about 41c, so I gained 5 degees.

Can lapping destroy a heatsink if you mess up?

Only if you use the wrong sandpaper - using less than 600 grit will probably make the heatsink worse. As for minor screwups, if you angle the heatsink wrongly or keep rocking it as you lap then you will develop a convex shape to the base, which won't sit on the CPU as well.

aznchaos said:

Can lapping destroy a heatsink if you mess up?

Click to expand...

you would REALLY have to Mess up to destroy a heatsink with sandpaper... lapping is basically just using finer and finer grits of sandpaper to polish the bottom of the heatsink

heh, hope this clears it up for you
max

So lapping will give me a temp decrease of maybe 5c? I bought the SK-7 and it has very tiny grooves that I could feel while running my finger nail over the bottom so would lapping help me out somewhat?

Nasdaq said:

So lapping will give me a temp decrease of maybe 5c? I bought the SK-7 and it has very tiny grooves that I could feel while running my finger nail over the bottom so would lapping help me out somewhat?

Click to expand...

most likely

when i get new sinks i use wet/dry sandpaper from ace hardware and the glass from a picture frame for a flat surface.

I'm running at 35degC idle right now(2100+ at 2200mhz) with my slk800 but i keep my fans turned way down.

I don't understand why people need glass for a flat surface. Does no one have a desk or does everyone try and lap on their waterbed?

Glass is the flattest and most flex-resistant surface that you will find in an ordinary home. Thick glass that is. Flat surface = flat sandpaper = flatter heatsink.

So you are telling me a desk is not flat enough? lol

7h3r4py said:

So you are telling me a desk is not flat enough? lol

Click to expand...

The question is.

is it worth risking it?

Most desks develop a sag over use, either a sag or wear that you won't notice until you lay something thats perfectly flat on top of it.

I know on my last desk, I wore 1inch concave into the edge of my desk over the years of using it. Thats where my wrists rested and slipped around on

Strange, seeing as glass is just a really viscous (sp?) liquid...

Mico said:

Strange, seeing as glass is just a really viscous (sp?) liquid...

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Yeah.... Glass sure is a liquid... I put that on the front of my car to stop 60mph winds...

lapping is very safe, i would advise using a mirror below the sand paper as they are very very smooth and even (same reason people use mirrors when doing coke) you should be able to find a mirror big enough around your house to can lap with. i would start with 600 grit paper, when the whole hs is hitting the paper and has even scoring across the surface move to 1000 grit then 2000, 4000, 6000, continue until you have reached the finest grit you can find, if you really really want a nice surface, after you have finished with the sandpaper go to your local hardware store and get a peice of metal that has been machined and polished (it is a must for you to make sure you get a metal that is harder then your hs metal), mild steel will work fine for aluminum, might have to get mildly hardened steel for copper, you will also have to get a few different lapping compounds, after the sandpaper you should be able to start with a very fine lapping compound and move to finer and finer compound, someone at the store may be needed to choose the right compound. put a small bit of the compound on the metal you bought, do the same thing you did with the sand paper, after each compound clean the hs and the metal with brake cleaner that you can get at a hardware store or auto parts store. continue as you did with the sand paper until you have finished with the finest compound, then clean the hs until you can no longer get ANYTHING off of the hs, the towel you are using will stay the same color no matter how much you clean. dry off the hs and you will have the smoothest hs you have ever seen, have fun.