Operation CPU & HS lapping

TheRift said:
http://www.techpowerup.com/articles/cooling/air/39

Scroll down to "Do I want a mirror finish?". Very interesting and makes sense too.
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I think what the writer means is that if the mirror image is achieved you have to cut down the paste drastically. The paste is only to take up the micro gaps not contacting between the surfaces thus as you aproach the ideal mirror image you need less compound. Still the better the mirror the better the contact. Its a case of maybe place a minute amount of compond in the exact middle/center of CPU HS, place HS down on CPU as straight/level as possible, press in latches, remove HS again and inspect the spread of the compound if the full base of heatsink/CPU is covered then you are Ok, if not clean everything and redo with a bit more until an ideal spread is seen (Max round circle) without any much compound visibly sqeezed out over the edge of the CPU

Mabe a bit of a waste but the final result will be more satisfying.

Remember that you should try and place the HS down flat/level and staright the first time as the evenly spread in all directions.
 
I am Penguin said:
Remember that you should try and place the HS down flat/level and staright the first time as the evenly spread in all directions.
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Vitually impossible if you ask me. A real biatch to install this heatsink and keaping it level.

Anyway, I'm done with the lapping now. The cpu has a dull mirror finish but the heatsink does not give me the same result although also sanded down to 1500grit and I know it's 1500 because everythime I changed paper I rotated 90deg to make sure I sand out the previous grain.. Must be a harder copper or something but I think it's good to go.
 
Yeah, sorry, that's kind of what I was getting at.

It's going to be a long run waiting for my new CPUs warranty to run out when I get it. :)
 
ponder said:
Vitually impossible if you ask me. A real biatch to install this heatsink and keaping it level.

Anyway, I'm done with the lapping now. The cpu has a dull mirror finish but the heatsink does not give me the same result although also sanded down to 1500grit and I know it's 1500 because everythime I changed paper I rotated 90deg to make sure I sand out the previous grain.. Must be a harder copper or something but I think it's good to go.
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Probably a very different copper alloy of sorts. Remember to clean off the surface with some acetone. I used to do alot of aluminium and other metal polishing and that fine dust gets into all the left over grooves.
 
ponder said:
Vitually impossible if you ask me. A real biatch to install this heatsink and keaping it level.
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I Know, the important thing is to at least try and that would be 100% good enought. If you don't try then the result of lapping could be negated.
 
That article contradicts itself slightly by first saying that all the water is flushed out between the glass and the lapped processor, and then saying that the mirror finish will cause a buildup of paste?

Surely if you screw that sucker down, between two very flat surfaces, then all the paste will be forced into the holes, with excess paste moving out the sides???
 
TheRift said:
Probably a very different copper alloy of sorts. Remember to clean off the surface with some acetone. I used to do alot of aluminium and other metal polishing and that fine dust gets into all the left over grooves.
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Maybe I'm missing something here, but surely you would want the fine dust to fill the grooves?? The metal will be more conductive then the paste and should therefore assist cooling?

Sorry if I'm missing the obvious, only had 9 hours sleep in three days....
 
Guys, this paste thing is not working. It does not spread all the way and when I add more the layer just gets thicker which is not what you want :mad:

So I scraped it really fine with a credit card using less than my previous 4 attemps and it's much thinner than any of my other attemps. Really I'm not usig much here.

Fark, I need a beer now.

EDIT: Well at least the beast boots so the cpu is still in tact :D
 
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R, sorry if this sounds daffed mate, but you may want to try burnishing compound (the stuff the panelbeaters use to polish out light scratches from a car's paintwork. It is really a grinding paste with ultrafine particles, which would probably give you that mirror finish you are after. You can buy some tomorrow at builders warehouse (most other paint shops will stock it).

If you really want to go the extra mile you can use Meguiars' Scratch-X, which would really buff it to a gloss. I know the "shine" is not what you're after but this is how I removed the bull-terrier's nail marks off the bonnet of my AMG! :)

Keep us posted, Rudi
 
Are you not supposed to outline the shape of the processor with tape, and then use the credit card to spread the paste, i.e. the paste is then the thickness of the tape?
 
rudirautenbach said:
R, sorry if this sounds daffed mate, but you may want to try burnishing compound (the stuff the panelbeaters use to polish out light scratches from a car's paintwork. It is really a grinding paste with ultrafine particles, which would probably give you that mirror finish you are after. You can buy some tomorrow at builders warehouse (most other paint shops will stock it).

If you really want to go the extra mile you can use Meguiars' Scratch-X, which would really buff it to a gloss. I know the "shine" is not what you're after but this is how I removed the bull-terrier's nail marks off the bonnet of my AMG! :)

Keep us posted, Rudi
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Rudi,

I did actually buy burnishing compound and I did try it as well. My conclusion, put two days aside to rub your ass off because it's like facial cream, not worth it. Better to go 2000grit paper if you can find some.
 
DJNgoma said:
One of the requirements in the OCC guide lol. Just apply the paste and test. Kind of retarded to lift the HS and check that it's spread, no offence I am Penguin.
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Read again my dear, I stated clearly not to disturb the HS once the unit is placed on the CPU.

The exersize of lifting and checking was just merrily to determine the exact amount of compund required/to be used for the specific degree of lapping. Then the HS/CPU must then be cleaned and redone before final placement.;)
 
rudirautenbach said:
R, sorry if this sounds daffed mate, but you may want to try burnishing compound (the stuff the panelbeaters use to polish out light scratches from a car's paintwork. It is really a grinding paste with ultrafine particles, which would probably give you that mirror finish you are after. You can buy some tomorrow at builders warehouse (most other paint shops will stock it).

If you really want to go the extra mile you can use Meguiars' Scratch-X, which would really buff it to a gloss. I know the "shine" is not what you're after but this is how I removed the bull-terrier's nail marks off the bonnet of my AMG! :)

Keep us posted, Rudi
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Of the two properties, obtaining a flatter surface is far more important than a smoother surface. A mirror finish is nice, but as mentioned above, it does not mean that the contact surface is flat. Also, it is quite impossible for us to manually polish a surface to a mirror finish without using some kind of polishing agent. Using a polishing agent is highly discouraged, as some of the polishing agent will remain on the surface and contaminate the contact surface, reducing the effectiveness of the thermal paste
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From previous link!
 
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DJNgoma said:
One of the requirements in the OCC guide lol.
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I read that and ignored it. I should have got some beer with the rest of the stuff. So for those of you following this, remember the beer and don't be an idiot like me. It's a crucial part of the procedure :D

PC is up and running which means my CPU survived the ordeal. Gonna let it run for a little while to get up to idle temp as I suspect it is still cold or this is working very well.
 
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rudirautenbach said:
If you really want to go the extra mile you can use Meguiars' Scratch-X, which would really buff it to a gloss. I know the "shine" is not what you're after but this is how I removed the bull-terrier's nail marks off the bonnet of my AMG! :)
Click to expand...

I r require pictures of AMG. :D
 
ponder said:
I repeated that 4 times before deciding to spread it rather.
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The point was only to see the size of the spread, it would not look good as you lifted it off which should not be done normaly. If you lifted it and there is a nice smooth layer of compound left then it was to much. The spread should have been a roundish circle just the size of the CPU "cover"

Anyway I wish you luck to see an improvement
 
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