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Why solvent and a rag will not remove all of the thermal grease from your HS.

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The solvents won’t hurt the chip. As for lapping, do it once, apply Artic Silver and don’t worry about it. You will have to lap the chip again to get the Artic Silver off. I lapped my chip until the AMD was barely visible. If I needed to lap it again, just in case Nevin pulls a rabbit out of his hat, I think there is a little more room. By that time I am sure I will have another chip anyway.
This whole lapping thing sound dangerous. Anyone every tried the Soft Scrub cleaner? God knows everyone probably has at least 1 bottle of that stuff lying around somewhere. And should I use like a cotton cloth or what?
I've only lapped once before....only out of necessity..the cpu & heatsink didn't connect properly and you could see the gaps between hs & cpu...
The toliet bowl cleaner idea sounds good...another thing to try : Scrub Free Soap Scum Remover...it dissolves damn near anything.

btw...good article :)
Like I said in another category, I just use turpentine and an old tube sock. Cleans just fine. I count on the microscopic porosity to hold the thermal grease in place so it can do its job. No lapping on the proc, only the HS.

BTW, after honing the HS down with a couple fine stones (300, then 600), I switch to jewler's rouge for a final polish. For those with the necessary power tools, you could use automotive valve grinding compound then switch to the rouge, but this requires three different poloshing wheels dedicated to the purpose in order to do it right.
plane old rubbing alc will do it

celly 566@986 it aint no p3 but for 60 bucks lol
Please make your logo image smaller CooperTown Bob, you're screwing up all the formatting!

That is exactly the point of the article, rubbing alcohol and a rag only cleans off the visible material. It cannot remove the material from the microscopic pores in the metal. The heatsink only "looks" clean to the naked eye. At the microscopic level, it is still massively contaminated. This is why the FBI lab can find human blood on a knife even if it has been cleaned and scrubbed and washed 100 times.

To really understand the difficulty removing thermal grease, you have to look at the world at a microscopic level. A level where over 300 micronized silver particles would have to be stacked on top of each other to reach a height of 1/1000 of an inch. A level where trying to clean the grease out of the pores in the metal with a rag or paper towel is like trying to clean grease out of a coffee cup with the trunk of an oak tree. When the finest fibers on the rag or paper towel are 100 times larger than the pores, there is no way they can get into the pores to clean.

This ir rather like beating a dead horse, since I mentioned it earlier in this thread, but don't you think the molecules of the oil carrier for the silver solids are smaller than the solids? That being the case, wouldn't they be the more likely component to be filling those pores? When you apply a fresh coat of AS, the same oil would again fill those pores. So, what is the harm in leaving the old oil in those pores? At some point there simply has to be a diminishing return syndrome when cleaning the HS.

I used the ENGINE DEGREASER I had in the garage (you can find it at the grocery store) to remove the old thermal pad from my FOP32-1 and it worked great. Then I cleaned it with rubbing alcohol & a lint-free cloth (had one with my old glasses) put a little Arctic Silver2 on CPU, smoothed it out with a credit card so I had a very thin even surface, and mounted the FOP32-1 back on my 1.1GHz TBird. Job done and running well at 1.33GHz.

I like overclocking but that lapping stuff didn't appeal to me because I didn't have the sandpaper, didn't want to spend the time to do it, and felt the work above got me 80% of the way there.

My guess is that the ENGINE DEGREASER would do a good job on thermal grease as well.

Hinge out
TriChlorEthylene is the one to beat, but it's hard to find since it;s on the naughty chemical list. TriChlorEthane comes close, but if you can find a solvent with a little Methylene Chloride in it, (also on the naughty chem list) you will fare better. It attacks many plactics, so use care. Brake Degreaser is an excellent, readily available solvent for these kinds of jobs.

For all of those who think that a rag and solvent won't clean off all the compound, listen up! Metal is NOT porous enough to absorb ANY of the thermal compound into the matrix. The only metals that can absorb are Powder Metallurgy metals, which are sintered powder particles that leave pores inside the metal matrix. This is the process that is used to make oil impregnated parts. Heatsinks and cores are NOT powder metallurgy parts; they cannot absorb thermal compound, or the oil in it. The only compound left will be residue in the *macroscopic* valleys left when sanding. The valleys will be only as deep as the finest sandpaper you used. They are regularly spaced and of even depth (NOT LIKE THE ARTICLE PICTURE). If you just scrape off the old compound, then you will have the old stuff still in the valleys. But when using a solvent, the solvent actively dissolves the compound, even the compound in the valleys. The rag does not scrape the compound out of the valleys, it absorbes it out, carrying all of the dissolved thermal compound with it. The referenced article is for a semi rigid object being used to *scrape* the compound out of the heatsink, not for a solvent situation!

Furthermore, the valleys are so small and shallow, I would guess that 90% of the old compound can be wiped off due to the flexibility fo the rag fibers and their small size WRT the valley size.

Again, the referenced article does not apply to 1) lapped metal 2) rags and solvent being used. I don't see how you can use it to invalidate the rag+solvent method of removing thermal compound. Its comparing apples and oranges.

Four points.

1. The abrasive particles on any grade of sandpaper are not all uniform in size. There will be a maximum size, but many of the particles will be 1/2, 1/4 or even only 1/8 that size. Thus the "Groves" in the bottom of the heatsink will not all be uniform when viewed under a microscope.

2. Very few solvents actually dissolve silicone oils or polyol esters, the two most common fluids used in thermal greases. (Thermal pads are paraffin wax based.) Most people and hardware testers clean their heatsinks with isopropyl alcohol, which dissolves neither silicone oil nor polyol ester.

3. Even fewer solvents dissolve zinc oxide, aluminum oxide, aluminum, or silver; the thermally conductive particles actually used in thermal compounds.

4. The finest fibers on the best cleaning cloth are 15 to 30 microns in diameter. The finest fibers on paper towels are 30 to 60 microns in diameter. The valleys in the heatsink are as small as 3 microns in diameter. It is a very tight fit.

I agree that with solvents that are unavailable to most people and special cleaning cloths that very few people have, that you could probably get 90% of the old thermal grease off. But read the posts in a variety of forums and look at a few thermal grease comparisons on hardware sites. The most common cleaning method is a paper towel with about 1/3 of the people using it dry, 1/3 using isopropyl alcohol, and 1/3 using acetone, WD40 or lighter fluid. Almost all of the comparisons or tests are on stock unlapped heatsinks. Can you estimate how much of the old thermal grease or melted thermal pad these people are getting off of their heatsinks and the validity of their thermal interface comparisons?


When I mix toilet bowl cleaner and zincoxcide based thermal compound it bubbles and pops and fizzes. Do you think this reaction is taking place because of zincoxcide or the silicone. I'm just curious. How much more/less effective do you think acid based solvents are in comparison to non-acidic alcohol or degreaser based solvents?
You know what?? This is ridiculous. If you're that obsessed with cooling, just say screw aircooling altogether and use a water cooler or Peltier setup. It's ridiculous to spend more on industrial strength solvent and sandpapers than a frickin water-cooler!

I'm just gonna say screw it, put on isopropyl rubbing alcohol on a paper towel and hope for the best. It's not as if a Celeron dissipates that much energy anyways.
I just use 90%+ Isopropyl alcohol and it gets most of it off. If you say you have to lap the heat sink, then how is the core of the cpu or GPU or whatevr any diff. It to has micoscopic pits that could hold the old thermo grease right? So you would have to lap them too.

I use a Alpha p3125 for cooling my p3 700 @ 1120 and get full load temp in the low 30s. So to me the gain of a couple degrees f. isnt worth lapping everthing. Are people having some major temp problems from not lapping when appling a new thermo compound? Guess I havent seen anyone complaining but dont really keep up onthe cooling seen.
hmm, i have used 1-1-1 trichloroethane. Works really well, but i think i will lap between applications of goop. good post!