Lapping success

shoman24v

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Smoove910 said:
There's always the chance your IHS (Integrated Heat Spreader) is not making good contact with the core. In this case (for extreme) you could always remove the IHS using a razor blade and try mounting your heatsink to the bare core. Sorta like the Athlon XP's....

All depends on how dedicated you are on getting your temps down.
I'll pass on that.
 

Sandman

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I second the argument of not polishing. Sure, I admit, it looks awesome. But IMO, it's a waste of time and money. I never go beyond 600 grit, I doubt there are any significant gains past that.

I also don't know why people say no circles. I've always used figure 8's, rotating the part 90 degrees after ~10-20 repetitions. I'm sure both ways are perfectly valid, maybe circles ruin the polish? :)

Oh, and I invested in a 1.5'x1.5' piece of glass about 5 years ago and it's lasted me through many lappings (most recently last weekend, for my server I'm building). A countertop should be ok, but for perfect flatness you need something guaranteed to be flat. All I care about is that my heatsinks pass the razor blade test.
 

Zero82z

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The thing about polishing is that some polishing compunds contain chemicals that block heat transfer, so if you polish a CPU or heatsink you could actually be hurting its heat transfer capablilities. Remember, it's not how shiny it is, it's how flat it is.
 
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Thats why U use metal polish, as it doesnt leave a residue. Meguiars makes a good one, or U can use Denatured alochol, as it leaves a nice shine (it is fuel oil after all)

As for the 600 grit comment, I usually see a substantial gain in polish and depth of scratches (they are almost invisible) at 800-1500 grit. 2000 grit and 2500 just get out all the imperfections. After that, your right. 400 and 800 are used to get the big "scratches and gouges" and the high grit is just to perfect what you did with those 2 at the beginning.
 

darktiger

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After you guys lap the HS and/or CPU do you apply AS5 at all?
 

454Casull

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solobaricsrock said:
Thats why U use metal polish, as it doesnt leave a residue.
That's not what I hear...
Meguiars makes a good one, or U can use Denatured alochol, as it leaves a nice shine (it is fuel oil after all)
No it isn't.
 

Brahmzy

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I wouldn't recommend polish either. Just use a very high count wetsand. They've got 'em all the way to 3000 and above.

If you do polish it, I'd take at least a few passes with the wetpaper and thoroughly clean it before you install it. This will remove any residue.
 

nooh

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I did mine last week and I was amazed to see it had copper underneath , i did it to make sure that the coolaborotory liquid pro was safe with this stuff


Did some lapping and its copper underneath
 

Erasmus354

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nooh said:
I did mine last week and I was amazed to see it had copper underneath , i did it to make sure that the coolaborotory liquid pro was safe with this stuff


Did some lapping and its copper underneath
I would advise against the coollab liquid pro...unless of course you never plan on ever switching heatsinnks or processor ever again. That stuff has a habit of seizing up tighter than, well lets just say its a real PITA to pry the two things apart once you use that stuff. Just stick with AS5.

And once again about the polishing. Shiny means jack shit, flatness is everything. It isn't the residue that is a problem with polishing, it is that when you polish you make the surface less flat then it was before. You aren't significantly removing any of the microscopic holes anyways with polishing.

Also some heatsinks have a very good lap job from the factory. I know that the Little River Storm is lapped to such a flatness that any lapping you try to do to it will actually hurt.


Its not about teh shiny!!!
 

ChingChang

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The reason why a surface is shiny/reflective is becasue it is FLAT. If it is perfectly flat, light will reflect off of the surface at the same angles. If it has very small microscopic valleys, most of the light will reflect at the same angles, but some won't (where it hits the valleys) so the image reflected will appear blurry.
Example of a rough surface reflecting an image:




If you lap a heatsink good enough, it will appear like a mirror and reflect light almost perfectly.
Here's an example of a lapped heatsink with a "mirror finish": (no polish used)




If you lap a heatsink but don't get that mirror like finish, it's not flat enough. If you then polish it with some crap, the polish is what will fill in the gaps and make it appear reflective/flat. But you don't want polish filling in the gaps. You want thermal compound filling in the gaps. It conducts heat better.


rest of the images if anyone cares:
http://www.systekonline.com/upload/...e&userid=2&folder=public things/HR01 heatsink
 

ChingChang

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Yeah it scared me too, which is one reason why I don't use that heatsink anymore. It has terrible mounting clip, and it would always twist around so I just used zip ties to hold it in place. And no fan clips so have to use zip ties for that.
 

indokyne

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ahh ic. nice quick fix.

great job on the lap too btw.
you must be bouncing off the walls with all that redbull in you.
 

Erasmus354

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ChingChang, I am sorry but mirror finish does not mean a flat surface, it merely means a smooth surface. However smoothness is not the first thing you want when you lap a heatsink.

You say that the measure of flatness is how well something reflects light...well riddle me this, does a parabolic mirror reflect light well? (Most certainly yes) Now is a parabolic mirror flat? (Most certainly no)

This is the problem you run into when you polish a heatsink. Sure you make the metal shiny, but you are taking away some of the FLATNESS which is the most important thing. Let the thermal compound do what it is supposed to do, and fill in those tiny microscopic gaps between the metal. If you have the heatsink flat that is all that matters. If your heatsink is slightly concave or convex as a result of polishing it to pretty, yet thermally meaningless mirror finish, then you have poor contact and need more thermal compound to fill the resulting gap left by the non-flatness of your heatsink.
 

ChingChang

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Erasmus354 said:
ChingChang, I am sorry but mirror finish does not mean a flat surface, it merely means a smooth surface. However smoothness is not the first thing you want when you lap a heatsink.

You say that the measure of flatness is how well something reflects light...well riddle me this, does a parabolic mirror reflect light well? (Most certainly yes) Now is a parabolic mirror flat? (Most certainly no)
Hey, I said if the surface is perfectly flat, light will be reflected off at the same angles and you will get a mirror finish because of this. I never said that a mirror finish means the surface is flat. Read my first sentance.

I did however say "If you lap a heatsink good enough, it will appear like a mirror and reflect light almost perfectly.", which implies the heatsink was lapped correctly, so it should be flat if done correctly.


It's a fact that if you're not getting a mirror finish, the surface still has imperfections. If you lap it correctly it should be flat and not curved at all.
 

Jodiuh

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Oh come on now guys. Neither of you are advocating polishing and I'm thirding that.

As an aside, my ninja has a "floaty" feel to it, much like your HS did ChingChang. After a lan party, I notice temps going up where they shouldn't be, lol! With the Zalman 9500 and it's nice screws...well, I don't have that problem.
 

nooh

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Got mine nice and flat and I ran it against the Heatsink plate to see it touched flat and no light was showing through , Hopefully will have the 590 board in the next week or so, I am just going to use the cpu once so I am not that bothered if it gets stuck, i have seen both cases with the french guys and both exposed it to aluminium (coolaborotory liquid pro), if more care was taken then I personally do not think it would have happened.

The second guy that was trying to take it off with a wrench , now he does not tell us this that the thing that holds the cpu has aluminium around it(it is a pentium).

If it was covered with insulation tape then I do not think it would have got stuck that bad.

Anyway I would like to experiance this first hand , I am aware of the risks and I dont mind.
 

Erasmus354

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nooh, just putting the two together and checking for light will not show you flatness or how good the contact you are getting. The only way to tell is to put a dab of thermal grease, then attach the heatsink. When you remove it you check and see if you have an even spread. Then you know everything is good. Your heatsink and IHS could only be touching on the outside and not the middle (most important part) and you would never know with your method.

Also, I have seen cases of someone who has a copper waterblock cemented to his cpu with coollabpro, and no there is no aluminum in sight.
 

Jodiuh

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Erasmus354 said:
Your heatsink and IHS could only be touching on the outside and not the middle (most important part)...
Like this...


 

nooh

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Erasmus354 said:
nooh, just putting the two together and checking for light will not show you flatness or how good the contact you are getting. The only way to tell is to put a dab of thermal grease, then attach the heatsink. When you remove it you check and see if you have an even spread. Then you know everything is good. Your heatsink and IHS could only be touching on the outside and not the middle (most important part) and you would never know with your method.

Also, I have seen cases of someone who has a copper waterblock cemented to his cpu with coollabpro, and no there is no aluminum in sight.
cool on the case now
 

nooh

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When i was trying to take it off it was very difficult and was like if it was stuck like glue , which looks like a good sign
 
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