What grit sandpaper for a heatsink?

lastig21

Platinum Member
Oct 23, 2000
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I just got my heatsink in from compuwiz1 (great guy) and after scraping off the TIM, I've put small scratches into the copper plate. I was going to sand everything smooth again and am wondering what grit sandpaper to use. Any info is appreciated.
 

Viper GTS

Lifer
Oct 13, 1999
38,107
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First off, you should have used a solvent & your fingers to take of the TIM. Goo Gone works great.

But since you've scratched it, start out with 320 or 400 until you can no longer see the scratches. Then go to 600, 800, 1000, 1500, & 2000.

That will put a mirror finish on it if you take the time to do it right.

Viper GTS
 

SuperT

Senior member
Jun 7, 2001
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look in the cases and cooling threads area, you will find lots on this topic.
;)
 

eshtog

Diamond Member
Jun 7, 2001
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uh oh! I was getting off the thermal pad on my heatsink and I put in a lot of good scratches in it what should I do? does it matter?
 

AMDPwred

Diamond Member
Mar 22, 2001
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<< uh oh! I was getting off the thermal pad on my heatsink and I put in a lot of good scratches in it what should I do? does it matter? >>



Same here:(
 

Quickfingerz

Diamond Member
Jan 18, 2000
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I remember doing some testing and sanding under any sandpaper makes things worse. Why? You make the surface uneven. Some parts you'll scratch more and viewing with an x-ray. you can see that thereare too many gaps. If you can sand a PERFECTLY flat surface then go ahead. It seems as if you are trying to remove scratches. eliminate those scratches then leave it as that. Don't make your cooling any worse.
 

eshtog

Diamond Member
Jun 7, 2001
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what if I dont sand will I be screwed? what if I leave it the way it is and just install the HSF?
 

Viper GTS

Lifer
Oct 13, 1999
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433
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Some tips...

- Buy wet/dry sandpaper, you'll need water up to 1000 or so, 1500 &amp; 2000 can be done dry.
- Go get a piece of scrap glass from a hardware store. You want a perfectly flat sanding surface.
- Keep the HS level. Go as slow as you have to, but keeping it level is vital. Otherwise you'll end up with a curved surface.
- Don't skimp on the time. It's tempting to move too quickly from one grit to another, but take your time.

If you do it right you'll end up with a mirror-like surface that's MUCH flatter than when it came.

Viper GTS
 

gygheyzeus

Golden Member
May 3, 2001
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You know what I find takes off a thermal pad really easily? Take the lid of a pen and gently scrape away at it. Plus, since the pen is plastic, you've got no chance of do anything dumb.
 

Viper GTS

Lifer
Oct 13, 1999
38,107
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You know what I find takes off a thermal pad really easily? Take the lid of a pen and gently scrape away at it. Plus, since the pen is plastic, you've got no chance of do anything dumb.

It tends to leave streaks of TIM. I just squirt a decent amount of Goo Gone on them, &amp; start rubbing with my thumbs. It takes a minute or two, but it will dissolve nicely.

Viper GTS
 

Viper GTS

Lifer
Oct 13, 1999
38,107
433
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It totally depends on the depth of the scratches, where they are (eg are they where the core will be contacting), etc.

Lap it if you want the best possible connection.

Viper GTS
 

eshtog

Diamond Member
Jun 7, 2001
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maybe I might not because you can see the scrathes but can really feel them when you run youre hand over them just a little you can feel them
 

Viper GTS

Lifer
Oct 13, 1999
38,107
433
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It's not all that much work, &amp; it guarantees a good interface.

It's a little time consuming, but if you're serious about cooling do it.

Viper GTS
 

Midnight Rambler

Diamond Member
Oct 9, 1999
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If you're leary of doing it yourself, you could always take it to a good machine shop and have them do it for you. Tell 'em to glassbead it while they're at it ... ;)
 

Bleep

Diamond Member
Oct 9, 1999
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If you decide to lap it with a piece of glass and emory I suggest that you move the heatsink in a figure 8 this will eliminate any chance of a convex surface.
Bleep
 

sad

Senior member
Jun 15, 2000
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Eh... just go to your local autoparts shop and buy the 3m sandpaper kit. Go above 800 if you're really really REALLY bored.;) I just let artic silver take care of the rest.
 

Mday

Lifer
Oct 14, 1999
18,647
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600 grit is what is the highest grit commonly found at hardware stores. it's not fine enough for flattening a heatsink surface.

1000 grit and higher is needed.

viper is quite correct on how high it should go.

but if you DO go that high, get arctic silver 2 which has finer particles of silver since using EXTREMELY fine grit paper will decrease the &quot;gaps&quot; of the heatsink requiring as2.

after you get the mirror shine, don't touch it.
 

sad

Senior member
Jun 15, 2000
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Another person's opinion. Believe what you want to believe... I have better things to do with my hands then lapping a heatsink for hours. er..no comment.;)
 

RanDum72

Diamond Member
Feb 11, 2001
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Whats the purpose of Arctic Silver and thermal grease anyway? Aren't they suppose to fill in the gaps so that the HS and CPU have proper contact?