• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

First Time Lapping

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

Lunar_Lamp

Member
Joined
May 5, 2005
Location
UK
I joined these forums less than a month ago, having absolutely no idea whatsoever what lapping was. This evening I have just completed my first attempt at it, so thought I would recount my experiences so that any other newcomers can discover this at some later date and learn from my mistakes, and be encouraged! (sorry for poor picture quality)

Ok, before I started I had this:
Beforeresized.jpg



90minutes later I had this (and a pair of very wet trousers :p ):
Afterresized.jpg


I felt this was a pretty good result considering the highest grit I could find was 1500!

Now I'm not going to recount the precise details in here of how I got from A to B, as there is a lot of detailed information out there on how to do sp, and following it will yeald good results it seems. I would just like to say a few things to those considering trying this for the first time.

Firstly, it is easy. It's not complicated to understand, and it's not particularly time consuming either, you could even do it whilst watching tv!

Secondly, go easy on the water. If you overload the wet and dry paper with water, it seems to stick a little, so don't try and do it under running water like I started off doing!

Thirdly, cleanliness is next to Godliness has never been more true. Concentrate on keeping the paper clean of little specs of dirt that might fall onto the paper, as these will cause havoc with the heatsink!

Fourthly, use a really smooth surface to work on. I started on a piece of chipboard, and that did not cut it. I needed a piece of glass, which was located in the fridge - as the bottom shelf. Borrowing that for a little while shouldn't cause too much hassle, as long as you clean it well both before (see above for why) and after use.

Fifthly, don't get disheartened when you see new scratches appearing, or if you make a mistake (like dropping it onto a concrete paving slab :bang head). Ok, so these will take a little time to work out, but they will go eventually.

Sixthly, don't get disheartened if you don't seem to be getting anywhere. I was about to give up after about an hour, until I looked at the surface from an angle, instead of directly head one - and I could see a proper reflection! This redoubled my workload and spurred me on; don't give up!

Finally, give it a go! All the wet and dry paper cost me only £4, and I have plenty left over; so it's cheap, you can't really break the heatsink, and you willl probably improve it!
 

infinitevalence

Member
Joined
Nov 14, 2002
Location
Nashville
you can check the flatness of your lapp job using a screen window, just set it near the window and look at the reflection if all the lines from the screen still look straight then you have lapped it well. Just remember that flat is the goal not mirrored.
 

dogooder

Member
Joined
May 30, 2004
Location
Minnesota
Good job Lunar_Lamp, my last lap job took 4 hrs, on a XP-90. ( no wet trousers though, lol). What were your before and after heat ranges?
 

Susquehannock

The Mad Smelter
Joined
Aug 26, 2003
Location
Maryland, USA
infinitevalence said:
you can check the flatness of your lapp job using a screen window, just set it near the window and look at the reflection if all the lines from the screen still look straight then you have lapped it well. Just remember that flat is the goal not mirrored.

Good idea - a piece of graph paper works well for the reflection too.

And I'm with you that the goal should be "flatness" not necessarily a perfectly
mirrored finish.
 

SolidxSnake

Member
Joined
Dec 26, 2004
thats a VERY flat surface. I like to use my mousepad as a flatness indicator (check out the thread in my link, and then check the lapping pics).. My zalman is heavily scratched, cause I placed it base down (wtf was I thinkin) on my marble bathroom counter while I was blowdrying it after lapping for around 1:30.. anyway, after I blowdried it, i picked it up with a thick cloth (thinking it was only somewhat warm). Damn, that copper is rediculous. burned my hand through the cloth. anyway, goes without saying, i kinda dropped it on the marble vanity top. not like a huge thud, but enough to put a small gouge in it.

Nice lap job. few tips though:

#1, spend more time on the last grit. maybe 5 minutes more than normal. it smooths the base out more at the end, makes it look better.

#2, this is a personal technique (from I.M.O.G., hope to see you soon dude, get that full-time job!), but instead of rotating the 'sink every few strokes, DON'T rotate at ALL. Stay in one orientaion at all times. better edges.
 

Susquehannock

The Mad Smelter
Joined
Aug 26, 2003
Location
Maryland, USA
Generally agree with #1 and #2 ... the only thing I can add is to clean everything with
water often, especially when going from one grit paper to another.
Don't want 800grit particles on your 1,000grit paper ;)
 

mjw21a

Member
Joined
Sep 29, 2004
Very true. I pretty much always forget to tell that to people though. A good thing you don't forget then Susquehannock.
 

mjw21a

Member
Joined
Sep 29, 2004
Just use finer grit sandpaper. Yes, you can polish if you want too, but who cares how pretty the base looks. You can't see it when its installed.