Lapping and Sliced bread

[Yyrd]

Just ordered my new I7 920. As i wait for Newegg to ship this new toy, I been reading. I am trying to get back upto date with my PC tech. Whats this Lapping thread? Oh, great idea! Flatting my CPU and heatsink. I think ill do this.

Then i think twice. Wow ,what if i ruin my CPU. what if i make a static discharge while sanding? How many ways can I ruin my $288 CPU. So i read more. I read everything i can about lapping. My end Opinion. Welcome to the latest Internet fad. This is one of those Email type scams where some litle girl was kidnapped at wallmart 2weeks ago,wrote 5years ago. Yet. this one people are doing everyday and people creating HOW-TO videos on Utube. How can they all be wrong.

"I gained 7c" ,after lapping one guy claimed. Sure I think these are valid Numbers. I think 90% of builders don't use grease correctly. I think this after watching 6 videos and reading 4 How-to-applie-grease threads.I've seen people simply coat the CPU head with a condom looking fingertip. I've seen other put a bubble of grease in the center and SQUEEZE the heat-sink and CPU. I've even seen a nail-polish-tool to paint on grease. All these declaring to be to correct way, as fellow internet users scream fowl-ball. It all left me with a bad taste in my mouth about these so called experts.

So, if you do not apply the grease on correctly , LAPPING is a great way to lower your CPU temp. but with the minor 0.001 imperfections on CPU, the grease if applied nice and thin; worked in all these imperfections. I don't see lapping as the next great invention since sliced bread. Now this will change my opinion if the Heatsink was cheaply made.

As always this is my opinion, I welcome anybody who disagrees with me. please do comment.

 

[4Ryan6]

Just ordered my new I7 920. As i wait for Newegg to ship this new toy, I been reading. I am trying to get back upto date with my PC tech. Whats this Lapping thread? Oh, great idea! Flatting my CPU and heatsink. I think ill do this.

Then i think twice. Wow ,what if i ruin my CPU. what if i make a static discharge while sanding? How many ways can I ruin my $288 CPU. So i read more. I read everything i can about lapping. My end Opinion. Welcome to the latest Internet fad. This is one of those Email type scams where some litle girl was kidnapped at wallmart 2weeks ago,wrote 5years ago. Yet. this one people are doing everyday and people creating HOW-TO videos on Utube. How can they all be wrong.

"I gained 7c" ,after lapping one guy claimed. Sure I think these are valid Numbers. I think 90% of builders don't use grease correctly. I think this after watching 6 videos and reading 4 How-to-applie-grease threads.I've seen people simply coat the CPU head with a condom looking fingertip. I've seen other put a bubble of grease in the center and SQUEEZE the heat-sink and CPU. I've even seen a nail-polish-tool to paint on grease. All these declaring to be to correct way, as fellow internet users scream fowl-ball. It all left me with a bad taste in my mouth about these so called experts.

So, if you do not apply the grease on correctly , LAPPING is a great way to lower your CPU temp. but with the minor 0.001 imperfections on CPU, the grease if applied nice and thin; worked in all these imperfections. I don't see lapping as the next great invention since sliced bread. Now this will change my opinion if the Heatsink was cheaply made.

As always this is my opinion, I welcome anybody who disagrees with me. please do comment.

If you lapp your CPUs heat spreader, your warranty is instantly gone, doesn't matter if its Intel or AMD, I would hope you at least read that part in all your knowledge gaining of the lapping guides, to come to your assumptions.

Members here that lapp their CPUs and Heatsinks know exactly why they're doing it, and they chose to share this information with others, in guides, that also may also be needing to gain some extra cooling margin, to get the highest overclocks they can possibly get from their hardware.

Its all about overclocking, and thats the THGF section you're posting this in.

This is a flame bait thread that you've started here, so we'll just see how it goes for now.

 

[jitpublisher]

Just ordered my new I7 920. As i wait for Newegg to ship this new toy, I been reading. I am trying to get back upto date with my PC tech. Whats this Lapping thread? Oh, great idea! Flatting my CPU and heatsink. I think ill do this.

Then i think twice. Wow ,what if i ruin my CPU. what if i make a static discharge while sanding? How many ways can I ruin my $288 CPU. So i read more. I read everything i can about lapping. My end Opinion. Welcome to the latest Internet fad. This is one of those Email type scams where some litle girl was kidnapped at wallmart 2weeks ago,wrote 5years ago. Yet. this one people are doing everyday and people creating HOW-TO videos on Utube. How can they all be wrong.

"I gained 7c" ,after lapping one guy claimed. Sure I think these are valid Numbers. I think 90% of builders don't use grease correctly. I think this after watching 6 videos and reading 4 How-to-applie-grease threads.I've seen people simply coat the CPU head with a condom looking fingertip. I've seen other put a bubble of grease in the center and SQUEEZE the heat-sink and CPU. I've even seen a nail-polish-tool to paint on grease. All these declaring to be to correct way, as fellow internet users scream fowl-ball. It all left me with a bad taste in my mouth about these so called experts.

So, if you do not apply the grease on correctly , LAPPING is a great way to lower your CPU temp. but with the minor 0.001 imperfections on CPU, the grease if applied nice and thin; worked in all these imperfections. I don't see lapping as the next great invention since sliced bread. Now this will change my opinion if the Heatsink was cheaply made.

As always this is my opinion, I welcome anybody who disagrees with me. please do comment.

I tend to agree that lapping your CPU is one of the more silly things I have seen.
It comes in right behind submerging you whole rig in mineral oil to keep it cool.....have you seen that one yet? :lol:

 

[SirCrono]

I beg to differ, I think lapping is pretty useful, but only if done carefully.

I'm considering a new rig now (an i7 920 or an i5 750, I haven't decided yet) and I will most certainly lap the HSF and will consider lapping the proc itself, the thing I'm most "scared" about is to screw over the lapping process, but I think I'll do fine.

I do agree with you about the TIM and the applying "instructions" found around in the web, I personally am a fan of applying a drop in the center and squeezing/twisting the HSF, (to spread the TIM more evenly in the center, which is IMO the most important part) but I haven't found a 100% foolproof way of applying it. I think this is partly solved through lapping, after all, the more even the surfaces are, the less need of TIM there is.

Anyway, if lapping mi HSF gets me 2 or 3 degrees less I'll be happy, if I can get 5 or more I might start recommending lapping to everyone.

The thing is, I'm already risking my proc when OC'ing it, so one more risk is not one big a concern.

Cheers and happy lapping (or not, depending on what you choose)

 

[Yyrd]

"It comes in right behind submerging you whole rig in mineral oil to keep it cool.....have you seen that one yet? :lol:"

I got to see this. now to explain the "Oil" wet spots from those pesky leaks under my desk....

 

[Yyrd]

About how to applie Grease.

I always took a razor blade.

I put grease on the CPU . push it as thin as i can get it. Change direction 90 degrees, and repeat till it as thin and smooth as i can do with my hands/eyes.
repeat with the heat-sink. Then i stick heat-sink on the CPU and try not to move it at all. Basically try to aim it and clip it in 1 move.

If i am wrong on this method, i guess i could add my name to the list of those call called experts i mentioned above.

 

[Guest]

Thermal Compound... a little dab will do ya! I usually use AS5 and put on about the size of a pea, and then spread it around with my fingertip. Then after that I use a razor and thin in out some more and put some TC on the heatsink as well (or the H50 as in my i5). It's worked so far, but as is the case with AS5 is it takes about a week to properly set and then you'll see some impressive cooling. Some use Ceramique, some use AS5 and some use that compound with diamond dust. As long as it isn't the same garbage they use on stock heat sinks, I am a happy guy.

 

[Conumdrum]

About how to applie Grease.

I always took a razor blade.

I put grease on the CPU . push it as thin as i can get it. Change direction 90 degrees, and repeat till it as thin and smooth as i can do with my hands/eyes.
repeat with the heat-sink. Then i stick heat-sink on the CPU and try not to move it at all. Basically try to aim it and clip it in 1 move.

If i am wrong on this method, i guess i could add my name to the list of those call called experts i mentioned above.

Yep.

 

[cletus_slackjawd]

I've always wondered about using Brass-O or some other metal polish, cleaning it off with alchol and cotton and then applying the grease with your finger on the other side of sandwich bag as to not introduce oils.

 

[Conumdrum]

Yyrd. Lapping can help. Only if your surfaces are wonky to start with. Funny post title, good job.

Take your chip upside down with the protective cover in your hand.

Place it on the plate of glass on the table that has a thing layer of ketchup spread on it. Push down, then look at the dispertion of the ketchup. You'll see the middle is thicker usually. After doing this to 20+ processors over the years you'll know when it's really concave.

Then do the same to the CPU heatsink. Hopefully it's convex, and it's really hard to do right since the HS rocks.

Or use a razor blade and shine a light from the other side and see the gap.

Many (most) CPUs are concave a bit. Good heatsinks might be a bit convex.

You actually want the CPU to be flat and the HS to be ohh so slightly convex. You want the absolute thinnest GOOD layer of Tpaste right over the spot on the CPU where the silicon (less than half of the metal top of the CPU) meets the top of the CPU heatspreader for best thermal contact. Tpaste is still somewhat of an insulator in comparison to perfect metal to metal contact.

So, in short, there is more to it. My best suggestion is don't lap to start. If your temps are fine on the install, then your good. If there is problems, troubleshoot and consider lapping as one of the last things you can do.

Ohh, applying Tpaste like you mentioned. Say you got a concave CPU and a concave HS. That neat ohh so thin layer leaves an air pocket. Nice! ACKKKK.

A small amount larger than a grain of rice, smaller than a small pea works great. having an exposed HDT heatsink changes application methods.

I'm not an expert, but done this stuff a bit more and read many top forums every day for the last 3 years. I'm reading other forums. My first computer was a Commodore 64 in 1983/4? My first PC was in ohh 1990? Every one was home built, I been at it a while.

 

[christop]

It only makes since lapping both so you have a perfect contact point help in heat transfer. I lapped my heatsink and chip and had a 5 degree drop. Read about thermal dynamics might help you understand..

 

[Conumdrum]

It only makes since lapping both so you have a perfect contact point help in heat transfer. I lapped my heatsink and chip and had a 5 degree drop. Read about thermal dynamics might help you understand..

A remount itself can have a variation on 1-3 C difference. Anythime you get a drop with a remount or a lap your good. But a 5C should be possibly a 2-3 C drop, unless you did 10 mounts at the same exact ambients and averaged under load, and then did the same with the lap. I give you this link as proof, and this is absolute pros testing cooling blocks.

Scroll down a bit and look at the different temps on each mount. Remember, this guy has probably done over a THOUSAND mounts, so he's pretty consistant.

http://vapor.skinneelabs.com/i7/Round2/Heatkiller/R2i7Heatkillers.html

 

[espslyxerx2]

Guys don't forget, some heat sinks are bought assuming the end user will lap them. A good example of this is the TRUE. These coolers come terribly finished from the factory, however once their lapped they are almost always on the top of best coolers as far as the last time I checked.

I have a lapped TRUE and E3110 at 4.3 ghz rock solid and stays under 60 C with full load. But again, there may be "better" coolers out now, however I still recommend the TRUE to people who want one of the best coolers AFTER lapping.

Good luck, don't forget to take a break every few minutes. Lapping is boring and time consuming but totally worth it if your willing to take the risk.

 

[JackNaylorPE]

"It comes in right behind submerging you whole rig in mineral oil to keep it cool.....have you seen that one yet? :lol:"

I got to see this. now to explain the "Oil" wet spots from those pesky leaks under my desk....

http://www.pugetsystems.com/submerged.php

 

[JackNaylorPE]

As always this is my opinion, I welcome anybody who disagrees with me. please do comment.

Well, here's one of the best coolers out there...read what they have to say about lapping:

http://www.prolimatech.com/

Lapping Warning!
Prolimatech does not condone any type of lapping done to the CPU or to heatsink base. Every Prolimatech's heatsink base is designed on a pin-point scale of how the base is to be flat and/or curved where it's needed to be. We have programed our machines to machine the surface in a very calculated way. Any after-manufacture lapping or modding done to the base will alter the design, hence negating its performance factor as well as its warranty.

As to the various best methods....lotta myths debunked here:

http://www.innovationcooling.com/applicationinstructions.htm

 

[LoneWolf_53]

Guys don't forget, some heat sinks are bought assuming the end user will lap them. A good example of this is the TRUE. These coolers come terribly finished from the factory, however once their lapped they are almost always on the top of best coolers as far as the last time I checked.

I have a lapped TRUE and E3110 at 4.3 ghz rock solid and stays under 60 C with full load. But again, there may be "better" coolers out now, however I still recommend the TRUE to people who want one of the best coolers AFTER lapping.

Good luck, don't forget to take a break every few minutes. Lapping is boring and time consuming but totally worth it if your willing to take the risk.

You've got that right.

I don't consider myself a glutton for punishment and if I weren't expecting significant improvement there's no way I'd even consider lapping.

I found myself the owner of a TRUE 120 though that was seriously warped on the bottom right out of the box.

I got the materials and chunk of glass and after about two hours of wearing my fingers down came to the realization that I needed more than just sand paper.

Luckily for me my best friend owns a lathe so we set up a jig and took about 15 thousandths off the bottom of that thing to get it flat.

Another ten minutes with lubricant and the sand paper and it is now smooth and level and somewhat closer to what I expected to get when I first opened the box.

To each his own but I'm not obsessed enough to mess with the CPU as it is not bad anyway.

Before I lapped it this TRUE matched the performance of my OCZ Vendetta 2 exactly and as far as I was concerned it should have been clearly superior based on all the reviews I've read.

There's no doubt in my mind that in this instance lapping was necessary and I'm just awaiting delivery of a selected CPU fan to go with my TRUE before I prove it.

 

[Yyrd]

need a valid un-biased test.

1 using valid grease methods/amount.
2 waiting 2-4 days for grease bonding.
3 using same chip, therefore normal none lapping if fist test.
4 un-baised tester who is not trying to prove a point.
5 load and unloaded readings.
6 use more then one type of heatsink. also report on the imperfections of each heat-sink.

suond good?

 

[4Ryan6]

need a valid un-biased test.

1 using valid grease methods/amount.
2 waiting 2-4 days for grease bonding.
3 using same chip, therefore normal none lapping if fist test.
4 un-baised tester who is not trying to prove a point.
5 load and unloaded readings.
6 use more then one type of heatsink. also report on the imperfections of each heat-sink.

suond good?

Are you volunteering for the job?

Because these tests have been run, application methods, different types thermal compound, many times in the past, and require a lot of work and time on the testers part, however what seems to be a serious question to you is old news to those of us that already know the answers, but you may claim us to be biased.

The reason to lapp a heat sink is to get better contact from a heat sink base that may be roughly finished, if you could get the 2 contacting surfaces microscopically perfectly flat, [Which is literally impossible], you wouldn't need any thermal compound at all.

I think theres a big misunderstanding of what thermal compound actually does, applying it to both surfaces is not necessary you're actually using twice over what you really need, you only want to fill the microscopic imperfections and if you use too much of it, it acts as an insulator instead of a conductor of the heat.

Most reasons for lapping a heat spreader on a CPU is to get higher OCs and lower temps from usually a CPU past its warranty anyway, as I've already said lapping the CPU voids your warranty, but it does give extremely good contact results, allowing almost no thermal compound at all.

Anyone here thats never even lapped a heat sink much less a CPU heat spreader, you really have no personal experience to share, so you're grasping for opinions, those of us that have actually lapped heat sinks or heat spreaders, know what we gained from doing it.

The choice is always yours of whether to go through the lapping process or not, but applying thermal compound is best done as a trial and error on the users part, mount the heat sink then remove it and inspect the contact footprint, if its squishing out, its too much, the least amount you can possibly use is the best amount, Period!

Theres nothing hard to understand about that.

http://benchmarkreviews.com/index.php?option=com_content&task=view&id=150&Itemid=62

 

[Yyrd]

i do not risk the $288 to lap a cpu. Also im an not experienced enough to do this. nor is my reputation valid for any to accept my tests. agree its alot of work. but isn't work how toms makes money? to offer an story idea can only be a positive. Hell i write like a 4th grader. this really takes any weight of me doing any test.

as all the others who have done tests, do seem on the bais side pro lapping, making them less a valid test for me. There more a how-to-threads. just become lapping is the new bandwagon does not make it REAL in any effect. this is why i referred to it as the latest email-scam, yes a poor analogy, but i think you understand my objective with it.

Seems people get really excited with shiny, shiny makes cheers, as lcd fans make $$ for shop builders.So those 2000 grit shines really pull more in the pro lappers. with out much logic entering these headlight-dazed heads. I am not anti-lapping, i am more playing the role of the devils advocate as the anti-lapping is a unrepresented minority. As many people did like i ,and read the sticky about lapping. We realy need another veiw before we jump into this very risky and costly experment. If toms is willing to sticky this pro-lapping-how-to people will automaticly think its SLICED BREAD.We trust anything from toms like its off the tablets of the ten commandments.

Its only fair to offer a complete story that shiny does not always equal better.

few pointers is. first don't you think intel knows how to build cpu right? if something as simple as lapping would make there product better, at least the highend cpu's will offer this?

why do the heatsink people scream in red ink, DONT LAP OUR HEAT SINKS?

we are talking about measurements as thin as rolling papper. just how thick is grease layer anyways?

isn't glass not flat and the taped sandpaper not flat too? so the end result is shiney lapping with imperfections? this is logical.

i heard that cpu are always curved one way, and the heatsink tend to curved the other way, suond like somebody knows what they are doing.

what does 3-7c help anyways? this is kinda picky. sounds rather hardcore extremist to risk all this time and money for a minor plausible improvement.

anyways, thank you for the good post ryan, your first one was less informative.

 

[arthurh]

To Yyrd

im an not experienced enough to do this

Agree

Hell i write like a 4th grader.

Agree

isn't work how toms makes money?

In part yes. Look at all the Articles written here. Also advertisers pay to have their wares displayed here because so many people come here to "LEARN" and help others to learn.

just become lapping is the new bandwagon does not make it REAL in any effect.

It is not a new way to do something. You happen to be in the "Overclocking" section. The people who come here looking for help hope to be able to get more performance from their PC using some or all of the practices of people who have Overclocked successfully. Lapping metal surfaces is one of those tools.

I am not anti-lapping, i am more playing the role of the devils advocate as the anti-lapping is a unrepresented minority. As many people did like i ,and read the sticky about lapping. We realy need another veiw before we jump into this very risky and costly experment. If toms is willing to sticky this pro-lapping-how-to people will automaticly think its SLICED BREAD.We trust anything from toms like its off the tablets of the ten commandments.

All stickies are "at your own risk" and say so. YOU do not have to do them and should not do them if you do not understand the risks involved or lack the competence That many require.

we are talking about measurements as thin as rolling papper.

Actually a lot smaller than that.

isn't glass not flat and the taped sandpaper not flat too? so the end result is shiney lapping with imperfections? this is logical.

No. That is your opinion from reading others experience and expertise.

i heard that cpu are always curved one way, and the heatsink tend to curved the other way, suond like somebody knows what they are doing.

You will hear a lot of information that can and is taken out of context to suit their means.

what does 3-7c help anyways? this is kinda picky. sounds rather hardcore extremist to risk all this time and money for a minor plausible improvement.

You are obviously not an overclock-er and once again state what is your opinion and not fact. Hardcore extremist????? Sounds like the kettle calling the pot black. Thats my opinion about what you are posting here.

Hope that cleared everything up for you.

Have a good day.

 

[Yyrd]

naa, i only do mild overclocking. i hate upping voltage. iVE FRYED a few cpu's in my life. /moment-of-silence. "extremist" has reached a new threshold i reckon.

why do you sound so angry?

 

[arthurh]

naa, i only do mild overclocking. i hate upping voltage. iVE FRYED a few cpu's in my life. /moment-of-silence. "extremist" has reached a new threshold i reckon.

why do you sound so angry?

Do you really think I am angry with you?

Not at all. Your statements are opinions only and I would not want some one coming here looking for good information to make more of them than what they are.

 

[LoneWolf_53]

To Yyrd

as all the others who have done tests, do seem on the bais side pro lapping, making them less a valid test for me. There more a how-to-threads. just become lapping is the new bandwagon does not make it REAL in any effect. this is why i referred to it as the latest email-scam, yes a poor analogy, but i think you understand my objective with it.

Your analogy is not only poor it's ridiculous.

Did it ever occur to you that just maybe some of these people you call biased are that way because they've experienced the improvements lapping made?

Seems people get really excited with shiny, shiny makes cheers, as lcd fans make $$ for shop builders.So those 2000 grit shines really pull more in the pro lappers. with out much logic entering these headlight-dazed heads. I am not anti-lapping, i am more playing the role of the devils advocate as the anti-lapping is a unrepresented minority. As many people did like i ,and read the sticky about lapping. We realy need another veiw before we jump into this very risky and costly experment. If toms is willing to sticky this pro-lapping-how-to people will automaticly think its SLICED BREAD.We trust anything from toms like its off the tablets of the ten commandments.

Seems more to me like you are the one lacking logic as the whole concept of lapping is based on scientific fact and you can play devil's advocate all you want that's not going to change.

few pointers is. first don't you think intel knows how to build cpu right? if something as simple as lapping would make there product better, at least the highend cpu's will offer this?

why do the heatsink people scream in red ink, DONT LAP OUR HEAT SINKS?

High end CPU's cost enough already and people buy them so why would Intel add another time and money consuming process to the equation when they don't have to? A step that would increase prices even further BTW.

You are really using a silly argument because the same could be said about auto manufacturers and just about every other product on the planet.

Auto makers could build a car that lasts a lifetime if they wanted to but what they give us instead is a balance of what they know we'll accept and what guarantees them continued profits. It's not unheard of for them to opt to go with a cheaper part or drop a process if the end result is still a running car that they know we'll buy. PC parts are no different in that regard.

The heatsink people scream don't lap because I'm speculating that they know many who try it will find themselves incompetent and perhaps even wreck the part or its effectiveness thus causing the manufacturer support problems that they'd naturally rather not address.

Also I doubt any of them would be too keen on admitting that they peddle a product that is sloppily made.

The Thermalright Ultra Extreme is one of the best examples I can think of as they are a very effective cooler but every one that I've purchased has had a base that's far from true (pun intended) and does not live up to its reputation without some extra work on my part. Look around the internet at how many users complain about the same thing.

i heard that cpu are always curved one way, and the heatsink tend to curved the other way, suond like somebody knows what they are doing.

If they were all that way yes it would make sense. So I can assume that if the CPU curves one way and the heatsink curves the same way that you'll agree lapping is in order?

what does 3-7c help anyways? this is kinda picky. sounds rather hardcore extremist to risk all this time and money for a minor plausible improvement.

Are you serious?

If you don't think 3C - 7C is a noteworthy improvement then I'm afraid you are doing an excellent job of displaying your ignorance.

If I could get a 5C improvement in cooling in every one of my PC's I'd lap everything.

Fact is though you don't get great gains on every piece of hardware and many are fine to use right out of the box.

My OCZ Vendetta 2 coolers all came adequately finished and lapping them would be nothing but a waste of time.

Others like the TRUE however you need to do some work if you expect to see anywhere near its full potential.

 

[Yyrd]

i think somebody needs to read the other side of the coin, this is my point. i found very little info besides the" flash and shine" of lapping. and less on what i found more logical information.

i know the argument, i read it. its one sided. somebody needs to do what i did and give the flip side, other then, "all thing come with inherent risk". Im sure alot of experts could validate my plausibility, if this is really a silly sham.

pity my writing skills are so off par i am not capable of providing an argument worthwhile , kinda hoped somebody else with better skill then i could offer there two cents.

i decided not to touch my prized cpu, and will lap my heatsink depending on its level of needing.

 

[espslyxerx2]

Im not going to touch anything above as I think everything has been explained well enough. However, some people just enjoy modding their pc's to make them different then the guys next door. Whether this includes internal pc mods that NO ONE will notice (such as lapping) to putting a bunch of LED's and cool fans inside the tower. Lapping is just the next step for some people.

I want my pc to stand out more then the normal Dell you see in every household. Unfortunately, the only thing that gets appreciated for custom pc's is the way they look and is ultimately the only thing people notice when they see my pc. I forget the statistics but something along the lines of less then 1% of computer users actually OC their system. The only positives anyone receives from OC'ing is possibly increasing their frame rate in Crysis and being able to brag over forums what clocks you were able to achieve. (Basically what im doing right now.)

After building a few pc's I was getting bored with the run of the mill build. So I started lapping everything I could just to prolong the building process and make the hobby last longer then just a few hours. I will never recommend to anyone to lap a cpu or heatsink. I would never want to take the blame for something that may happen.

Before this turns into a college paper: I lapped my E3110 and TRUE just because I could. I very well could have achieved 4.3 ghz without doing so, but wheres the fun in that?

I was able to achieve a great OC and keep the temp down to an acceptable level. I don't remember but I probably got another 2 - 5 C with the lapping which was totally worth it.

Im done.