Lapping heat sinks

[Snafu]

I received an Arctic Ice video cooler and the base of the heat sink for the cooler had a milled surface (you could see the milling marks). To clean up the heat sink, I separated the heat sink from the fan/shroud and followed these 4 steps:
- 220 grit to quickly take off the high spots,
- 400 grit to smooth it out a bit more,
- 1000 grit to give the surface a smooth feel
- Polishing compound to give the surface a mirror finish
(All of the sand paper was wetted with oil and was done on a glass plate)

I finally cleaned off the surfaces with acetone (no IPA around and no plastic was around to damage). The finsihed piece looked great (not quick perfect but not bad for the first time)

I thought I would post to find out other tricks for lapping a heat sink. Would you use a finer grit?

I woudl like to learn any tricks from others before I start lapping teh heat sink on a Zalman heat sink that should arrive soon.

[RotorHead]

Sounds like you got the process down :thumb:

I don't think you will see very much improvement by going with a higher grit.

I've seen some folks use a sharpie to mark lines on the bottom as a guide for keeping it perfectly flat.

Did the lapping give you any performance improvement in temps or OC...?

[Snafu]

Thanks for the news. Good tip about the sharpie :thumb: . With ALuminum being so soft it is important to keep it flat or you round off the edges.

Unfortunately, I did not test out the cooler before lapping the heat sink ( :hide: ). Even though it was brand new the milling marks were very evident (your nails caught on the groves) so I just delved into the lapping.

I have not even tested the new cooler as yet (running a number of tests on my case with different airflows to see which offers the best overall cooling - plan to post the finding). This cooler should cool the card better than stock and with luck even drop the case temp down a bit. I would expect the lapping will help but not to same extent as adding this cooler to the card.

I should test it out with the Zalman heat sink but with my FSB-challenged proc I am not sure if I can get over 235 even with the new cooler. My hope is that with the Zalamn I can get over 235 but if not I would hope to see a temp drop.

I will post all testing results as soon as I can. Work and summer interferes with testing :lol: .

[Snafu]

The Zalman arrived after issues with the posties ( :irk: ).

Unlike the Arctic Ice Cooler the base of teh Zalamn looks very clean and shiny. Doubt I will need to lap this heat sink.

Need to run a few tests with air flow (and rewiring) before I can post any improvements with these new toys (desk is now cluttered with parts just itching to get inside :lol: ).

[flexkill]

cool snafu, sounds like you got some work to do. BTW remember that 3.0c i was going to install. well i got kind of busy and it laid around for a few weeks. my nephew(who is also a oc freak)kept beggin me for it, it was getting harder and harder to keep him away so i finally gave in and sold it to him(very cheap i might add) any way he comes over and tells me he hit 262 fsb on air :yikes: :irk: you believe that crap!!!! screwed myself again :| :beat:

[Snafu]

Yeah lot's of testing to be done. Between new heat sinks for the video card and proc and then some testing on air flow (gotta a couple of 50mm fans for the ram and an extra 120mm for the hard drives to test out). I would not be surpised if my rig starts acting like a hovercarft :lol: . Gotta back up my raid first before I start mucking about inside (also goning to get the bios savior - recommend you look into it too - will have to try out a modded bios :mischeif: ).

:yikes: You gave it away :yikes: and cheap too! I wish I had uncles (or even family) like you :cry: . 262 on air. Holy Carp. Tres cool :cool: (lucky son of a... :D ).

One good thing about you not getting it installed. At least it's not covered in donut dust :D :rotflmao: .

Can you get any more from your vendor? (maybe I can convince them to send me one too).

[flexkill]

ya but before i get to excited i still have to see his claim of this great oc. he duz have the tendency to bs just a little. but actually i hope he did, i will find out soon enough!!! :mischeif: :thumb:

[Snafu]

Hopefully it's no BS. Sounds like a good chip. I want to get one but its hard to find on-line. I think the oly way to confirm a 30-cap is to visit the store and see it for yourself. I guess a 3.0C packed after Feb-2004 with 30 caps should be one of the good ones. (P.S. did you find it on-line or at a local store?)

Get your nephew to install MemStat from BE (just don't enter the score). It's pretty good at detecting stability. I found out after running seemingly stable at 240 then the QuickPi part of the test quickly froze my system ( :lol: ). Hopefully the Zalman will cool the proc enough so I can go higher (I will pull the chip off to see if it is a 30 capper or not). The Zalman is pretty smooth already so I doubt lapping will help this one.

[flexkill]

hey snafu, go to zipzoomfly.com. they are a trusted company and very friendly to the oc community. you can call them and ask them for what you want, they will chek and if they have you get. thats the way i went, great service and good prices....check it out :thumb:

[Gaspar]

I recommend using a marked (sharpie) and daw an X on the heastink srfae. Then using he same method ou were using. You can tell if its even when the marker dissappears evenly. 1000 is good but 1200 is better for the final product. Good luck :rotflmao: :rotflmao:

[Snafu]

Gaspar - Thanks for the great tips. I thought using a polishing compound would be even finer than 1000 grit and it gave a mirror finish.
The Zalamn arrived and it looks pretty good right out of the box. Not sure if it needs any lapping. The Arctic Ice video cooler certainly did need some lapping - milling marks were very evident.

[Gaspar]

I can honestly say though I havent really seen a temp differnece when Lapping. I do it for the piece of mind I guess.

[Hybrid-Mods]

I go all the way up to 2000 grit, provides the mirrior finish with out any polishing compound. When i Lap heatsinks i see a general 1-5 degrees drop in tempetures. But you have to remeber when you lap a heatsink.. you won't need much thermal paste as you did before.

Great Sharpie idea.. i'm gonna do that next time i lap mine

[Snafu]

I will have to give 2000 grit a try :thumb: .

Not sure how fine polishing compound is in relation to grit but I know it's fine. Though using paper is easier than compound.

Thanks

[Snafu]

I noticed that the smoothness of Intel procs leaves a lot to be desired. I think I coudl get a smoother surface with a grinder.

Has anyone tried lapping thier proc? All the printed code would go and RMA would not be possible but I thought I would ask to see if anyone has done this and if it worked well?

[Killer Munkey]

i saw a thread on tbreak.com about from a guy named QuadDamage who lapped his A64 and dropped 5c off his temps because of it. personally i'd be careful not to lapped it down to much at all, don't want to get the core by accident.

i made the mistake of lapping my already very smooth sp-97 and made it worse than it was before :( i still gotta find some good sand paper to go at it again.

[hey]

Yep- I've lapped our 3gig Northwood- I started with 600, followed with 1000, and finished with 2000 grit. For the wet-lapping, I used... umm, saliva. But after cleaning with alcohol, I noted a small (3C drop at load, no change at idle) using some basic DOW thermal compound I use at work. I'll play with some Ceramique at some point in the future to see if it helps more.

So much for warranties... :D

[Snafu]

So much for warranties... :D
So true and once you overclock the warranty is voided.

[timpanogos]

xp-120 came, the mill marks are VERY evident on this hs also.
the shapie tip looks very good ...
I also wondered about giving the cpu a once over ... wondered about
getting the wax out from the stock thermal pad I put on.

Questions ... the oil on the sandpaper.

The AS5 instructions say to keep oil far away... will the acetone and
good alcohol washdown remove all the oil from the "valleys"?

Also, you mentioned using flat glass ... how best to actually do the sanding?

I was thinking somekind of flat edge, I don't know, like 1/4" wide or something?

Any other hints appreciated!


Thanks

Chad

[Snafu]

I think the xp120 has a chromed copper base. I seem to recall someone lapping an xp120 but cannot remember where. Google probably woudl find it.

Once you start lapping you void whatever warranty you might have. Since heat-sinks are relatively cheap this is less of a concern. However, if you have a $1G FX55 or EE proc you might think twice about it.

I have had no problems with oil and a good cleaning. Acetone is a good cleaner but does have some downsides. It is very volatile and may evaporate too quickly. It is also an excellent solvent and by this could dissolve any plastic components or ink printing on procs (void your warranty). I use acetone myself if ther eis nothing nearby that coudl be dissolved and then some 99% IPA.

Make sure you get any lint of the surfaces before applying your paste and seating the sink. I think AS5 directions suggest rubing the surfaces with teh paste then add the dab in the middle. Check the site www.arcticsilver.com (if I have it right). It is also in the BE Links page.

I put the glass (stolen from a picture frame) on a coffee table, add the paper on top then the oil and the heat sink on top with a circular motion - less chance of irregular wear than if your go in one direction (same technique used to buff out a paint job). I wouldn't use a 1/4" wide flat edge - like a file - too many chances to get an irregular surface.

Try not to fold the paper around the edges of teh glass. If you need smaller piece then just cut the right size. Helps keep the paper flat. Ideally I think it would be good to glue the paper to the glass but the oil may not let it stick for long. I just recently picked up some rubbing compound that I want to try inbetween the 1500 paper and the polishing compound.

Oh one last thing - it takes a while to get it nice. So turn on the tube while you're doing it or you may become bored out of your skull :lol:

[harleybro]

Snafu I had just read an article on this over at XS the other day. It seemed like the common thought was up to 600 grit is where you would see results. When you take it up to 1000 it was more for the eye then any additional cooling help. If I come across it again I'll link it to you.

[Snafu]

Thanks bro :thumb:

I guess I like to see my face too much :o either that or the monotony of polishing up the surfaces (not much else to do in the cellar except maybe poke a stick at BB or glorfy :D)

[timpanogos]

hmmm, looking around most advise against doing the xp-120 - mine is nicked up a bit on the edges, but not in contact area ... when you read about the space of a fingerprint making a difference, those milling marks are mountains in comparision..

guess I'll as5 it up and give it a shot ... can always tear it down again ....

[boshuter]

Snafu I had just read an article on this over at XS the other day. It seemed like the common thought was up to 600 grit is where you would see results. When you take it up to 1000 it was more for the eye then any additional cooling help. If I come across it again I'll link it to you.

I think that's right, a mirror finish looks cool but isn't going to help your temps any. The main thing is getting it flat. I believe water would be a better choice than oil for the process; the only purpose of the liquid is to wash away the grit built up during the sanding. Use plenty of water to keep the paper clean. When they wet sand in a body shop they usually keep a garden hose running on the area, a wet sponge used liberally works very well also.