Lapping with Dremel sanders?

[fuzzba11]

I was about to attempt this on my CAK38, but wanted to know if it would end up doing more harm than good. The bottom of my CAK is ugly. See below. Is it possible to smooth it down with a 120 Grit sanding band? Or do I need to go get some regular sandpaper and do it manually? And what's this wet/dry thing people talk about?? Sanding it while it's wet??? Thx for the info.

[BrianCapps]

I'm not sure what a CAK38 is, but it looks like a heat sink or something. If it is, I would use a sanding block with a high grit.

Wet sanding is just sanding whatever under running water, such as a faucet. Not a good idea if you are lapping a chip ;)

[Sonny]

fuzzba11 - use normall sandpaper starting with 600. Put the sandpaper on a thick & extremely flat glass work surface & do a figure 8 pattern. That'll make sure you have a flat HSF. Take a look at the front page of this site & there is an article that does not suggest a mirror finish on a lapped HSF

[fuzzba11]

Oh yeah, RTFM, am I right? ;) Thx, though, I'll check some stuff out, just hoped I could save time/money/car ride by using my dremel :p

[Gabertooth]

fuzzba11,

Alright..I use a dremel and an abrasive band to take stuck on thermal compound off. But it would take forever to sand out the dremel marks if you use it first. Start with 600 grit and a glass sheet and move to 2000 grit for mirror finish.

-Gabertooth

[Monaco]

Hey bud,
try doing what sonny said. But if it is really uneven, try starting at 220 to save time, then 400 -> 600 and up but anyway-

Once you get past 600 use those little Q-tip looking polishing wheels on your Dremel to give a it nice finish & verify it is smooth. The place on Evans ought to have the right sandpaper for you if you can't find 600+ grit.

[William]

no no no no!

i went at a water block with a dremel to remove some as epoxy(the stuff would NOT come off, tried some freaky organic stuff and it failed) and it was not a good result. Use 600 and up sandpaper on a sheet of glass and slowly sand back and forth with even pressure. Go up in grit till you get the finish you like.

[fuzzba11]

Well, I decided to go and do my own thing...I tried out the dremel, but on the edge to test it out. I didn't like it, ultra uneven, although shiny...so I tried this orange bit thing I got with my dremel, but same results. What I ended up doing was using the side of a cutting wheel for sandpaper! Ingenius...it's a little scratchy, but it's a LOT better than it was before. If I have problems or time I'll take some proper sandpaper to it. Thanks for the response, now go check out my case in the gallery, dammit! :D

[fuzzba11]

Here are my results:

[CrystalMethod]

Be careful how much material you remove. Too much and that clip won't apply enough pressure to make the heatsink contact the surface of the die properly (assuming you're using the dremmel for this). Best bet is to do it by hand to avoid problems in the first place.

[fuzzba11]

To clarify: I just took one of the little cutting circles and put it flat on the HSF, not attatched to the dremel or a bit or anything, and rubbedit back and forth with my finger :p

[Monaco]

Looks good now! Do you have those little round cloth polisher dealies? Give 'em a try, worked for me. Good for removing old thermal goo residue instantly too.

[fuzzba11]

How do you attatch those suckers? They only have a pin sized opening, so they won't fit on the normal bit holders...

[Monaco]

Depending on which Dremel kit you got, you should have some "mandrels", same as the regular bit holders but with a sharp screw on the end, just twist it on good and the spin of the Dremel holds it on-

[fuzzba11]

ah, good call :p