How to Clean Thermal Paste Out of CPU Socket?

How would you clean up thermal paste if someone put it on the motherboard, where the CPU pins go. Been working on this computer for a bit, very odd stuff going on, finally pulled the CPU today.

And: :-D

Isopropal alcohol and compressed air? I will say I would not have thought on checking for thermal paste on the CPU pins as a no boot cause.

 

Plastic putty knife for the heavy stuff, high alcohol content rubbing alcohol w/cotton balls or q-tips for the rest.

And dude...thats wayyyyyyy too much paste for....anything.

 

Yep, that is like frosting on a cake. Might keep a bit of it, should have me in tp bidness for a while.

Joking aside, hopefully can get it cleaned up, we have serious compressed air at work, and get his computer going for him.

Of course, I will have to confiscate any thermal paste he may have at his house. :-D

After looking a bit more, there are bent pins on the CPU. When I removed the heatsink the CPU came off with it, and the locking bar was locked. Suspect it was not seated properly.

New one on me. :major

 

Crikey what a disaster rolleyes
Isopropyl for the worst but something like contact cleaner to finish up as it leaves no residue.

Something like this is very easy to obtain over here in Australia


but this is much better although harder to get as you need to go to a specialist electronics service supplier



I get mine from a company called Radio Parts and they are in Melbourne
Make sure it is not contact cleaner and lubricant like most other brands seem to be as you don't want to finish with an oily socket

Take it real easy on the compressed air as you may drive the paste to the bottom of the pins in the socket and then it will be near impossible to clean.

The commercial way to clean something like this would be with a large ultrasonic cleaning machine using isopropyl alcohol or another solvent in the tank and then fully submerse the entire board upside down in the tank and leave it to clean overnight. An ultrasonic cleaner this size would cost serious $$$ and most places only have them for small parts like you might find in a camera or a watch. Places that load panels of SMD (surface mount device) type PCBs with a pick and place machine that uses solder paste stencils would probably have a large ultrasonic cleaner as they often need to clean off solder paste from PCBs if the stencil goes out of alignment. Sometime these places will clean things for a small fee but they will be unlikely to offer any guarantee on the job.

Good luck and I think you will need plenty of it

 

Well the good news is I did not do it, so if I can't fix it, oh well...

Ultrasonic would be the way to go, but we just have the little ones, won't help with this.

Would heat help harden the paste to make it easier to remove? We have a digital heat gun, can set the temp very precisely. Don't want to melt or weaken the solder, but any thoughts on heating it up to 45 or 50C? This stuff is not hardened at all.

What a mess.... :-D

 

Heat won't help as heat sink compound is never supposed to harden and is designed for high temperatures. The best idea is find someone with a big ultrasonic cleaner but these are few and far between. Sometime metallurgy labs have big ultrasonic cleaners but whether they would clean it is another thing rolleyes

Disclaimer time rolleyes
Use this at your own peril Fred but if you are careful pure Acetone is much better at shifting the paste but try not to slop the Acetone on the PCB as it can affect some capacitors and some types of diodes. Short periods will be OK but don't leave it there to evaporate as it softens some plastics. When using Acetone I use a strong 10mm flat bristle artist's type paint brush like below and an absorbent pad of cotton waste or tissues. The method is to use the brush dipped in the acetone and then stab the area to be cleaned a few times only then immediately dry with the pad. Don't use the brush in a stroking action as you will just keep spreading the paste. The pad is what takes the pste away. Wait about 30 seconds between each application of the brush and repeat until clean. Doing it this way you are less likely to damage any plastic items that may be damaged by acetone. The acetone will probably remove the conformal coating and also the solder mask and definitely the silkscreen on the PCB so more reasons not to get it on the PCB if possible. If this happens don't stress too much unless you will be using the PC in the tropics and then an after market PCB sealer should be used
Remember acetone is both toxic and flammable and should only be used in a very well ventilated area.

The stiff flat brushes like below left are the best but the stiff round ones on the right of the picture are also OK but lose their bristles easier so you need to pay much closer attention. Personally I use either the number 8 or 10 brushes and I buy them 10 at a time. Try to avoid the crappy chinese brushes as they lose their bristles far too easily and go for quality hog's bristle brushes.
Don't use the soft tapered type brushes as they drop their bristles far too easily and don't clean as well



Fred, if this isn't working then there are some other strong solvents you can use but they are too toxic for me to suggest on the forum. If you pm me then I can make some other (more toxic) suggestions :major

 

Thanks Joffa, but I use enough chemicals at work, don't really want to mess with anything more than alcohol on my time off.

Think I am going to pull the plug on this one. I spent almost an hour cleaning it, got a lot of it off, but there is still a lot down in the sockets. It still won't boot, and the mobo only costs around $70 or so. Even at the 'friend' rate, it I would have to charge him more than that for cleaning it and the stuff I have done on it before, and there would be no guarantee it would even work.

 

You have a water pressure washer? Its free and fun. Dry it out for a night somewhere warm though.

Either way your buying as new motherboard so what the hay.

Could try a boiling hot kettle of water, it's not water soluable though.

The thing that cleans heat paste best are citrus cleaners, none toxic and powerful, try using some of that and then washing it away with boiling water.

 

maybe Arctic Silver ArctiClean Thermal Material Remover and Surface Purifier??
http://lmgtfy.com/?q=Arctic+Silver+ArctiClean+Thermal+Material+Remover+and+Surface+Purifier
And something to suck it out, like an aquirium pump?
http://www.instructables.com/id/Electric-Vacuum-Pen-From-Aquarium-Air-Pump/
http://www.instructables.com/id/Vacuum-Pump-from-Aquarium-Air-Pump/

 

Good links there, thanks. But I am not getting paid enough to go to that much trouble.

 

If I was the owner of that computer, I'd find the person who applied the thermal paste and rub his/her nose in it. Sheesh!

 

Trust me, was tempted, but "Let he who is without sin cast the first stone." came to mind. I have done plenty of stupid myself. :-D