Hardware Advices for Technicians Read Before Rework!

[psytr0nic]

black glue = oooop still fighting against it .. searching good solution for it .
sometime I lost Ic or Board pins due to it ... OMG ,, who will briing easy thing to remove it ?

[blu angel]

it's just so silly because sometimes the black glue extends to other parts that makes it more harder to remove the desired ic..


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[psytr0nic]

and often , even under ic ... i killing every day ...

[Argento7]

I just like to add a little comments. I ALWAYS clean PCB after work with an cheap toothbrush! Yes, low cost tool I know but 100% good. Maybe professional tools in market, just choose. But te thing is when you desolder/solder any IC on board, small pieces of welding beads can freely get stucked between pcb components. So, I clean ALL the PCB with my toothbrush! Sometimes with thinner (to clean flux (if conductive), somethimes dry.
Try and look your final work very clean.
BTW, I was searching solutions for "Black epoxy", an this is what I found:
...... FIRST OF ALL: some chemicals listed here are CANCER CAUSING SO BEWARE!!!!....

how to remove epoxy resin and smd chips - YouTube

We used to make our own by *slowly* adding sodium hydroxide pellets (one at a time; wait until pellet is dissolved before adding another) to 100% ethanol. A good, muddy brown color usually indicates the ethoxide is ready to use. You won't need much, only a few microliters to cover the section on the slide. Also, monitor carefully. The dissolution of the epoxy occurs fairly rapidly.


Epoxy Removal from Gold Fingers

http://********.com/2010/07/16/decap...uits-with-sap/
One of the biggest hurdles in this process has always been just getting to the guts of the chip. He used acetone to dissolve the plastic case but had trouble getting through the epoxy blob. Commonly, the epoxy is soaked in nitric acid for a few minutes but [James] didn’t have access to that chemical. Instead he popped into the local music store and picked up some rosin (used to make violin bows sticky enough to grab the strings of the instrument). After boiling down the rock-hard rosin and the chip for 20 minutes, he got a clean and relatively undamaged semiconductor that he can easily peer into.

[Wites OM Tesla]

Originally Posted by Argento7

I just like to add a little comments. I ALWAYS clean PCB after work with an cheap toothbrush! Yes, low cost tool I know but 100% good. Maybe professional tools in market, just choose. But te thing is when you desolder/solder any IC on board, small pieces of welding beads can freely get stucked between pcb components. So, I clean ALL the PCB with my toothbrush! Sometimes with thinner (to clean flux (if conductive), somethimes dry.
Try and look your final work very clean.
BTW, I was searching solutions for "Black epoxy", an this is what I found:
...... FIRST OF ALL: some chemicals listed here are CANCER CAUSING SO BEWARE!!!!....

how to remove epoxy resin and smd chips - YouTube

We used to make our own by *slowly* adding sodium hydroxide pellets (one at a time; wait until pellet is dissolved before adding another) to 100% ethanol. A good, muddy brown color usually indicates the ethoxide is ready to use. You won't need much, only a few microliters to cover the section on the slide. Also, monitor carefully. The dissolution of the epoxy occurs fairly rapidly.


Epoxy Removal from Gold Fingers

http://********.com/2010/07/16/decap...uits-with-sap/
One of the biggest hurdles in this process has always been just getting to the guts of the chip. He used acetone to dissolve the plastic case but had trouble getting through the epoxy blob. Commonly, the epoxy is soaked in nitric acid for a few minutes but [James] didn’t have access to that chemical. Instead he popped into the local music store and picked up some rosin (used to make violin bows sticky enough to grab the strings of the instrument). After boiling down the rock-hard rosin and the chip for 20 minutes, he got a clean and relatively undamaged semiconductor that he can easily peer into.

Of course toothbrush is best i know for cleaning boards after i use it for cleaning my teeth.

[gscardua]

A person told me that a toothbrush is very electrostatic and recommended that I stay away. This same guy recommended to use 450°C and medium air flow to solder/dessolder SMD components from iphone motherboard. As I can read from experts on this forum this is not true. I don't know what I think. Sorry my English and thanks.

[psytr0nic]

450° hummmmmmm too much bro

[ctflight13]

Hi mr wites !!!

Please can you post educational videos for change/repair PFC touch screen conectors for iphones and soldering 01005 smts ....

Thank you for helping us !!!
You are very good !!!
Best regards

[Wites OM Tesla]

Originally Posted by ctflight13

Hi mr wites !!!

Please can you post educational videos for change/repair PFC touch screen conectors for iphones and soldering 01005 smts ....

Thank you for helping us !!!
You are very good !!!
Best regards

Thanks i will try to make time and make some videos have allot of work.

[peeko786]

sir how can i remove glued ic?

[jegerjon]

Hello friends, I just wanted to share a method I have started using for removing the black resin surrounding the BGA chips. It has proven very good and is a lot faster than dental-pick and hot-air!

Enjoy

[Binoy.c]

Originally Posted by jegerjon

I was wondering what material people uses to replace the black resin around chips? Say you have removed the resin, reballed the chip, and want to add a new pool of resin, just to leave everything the way it was before. What materiel would you recommend?

removing glued ic is not simple as it is mentioned but if it is a regular work it may be also a simple one like other complicated hardware works the following steps should be in mind while removing a glued one with a themocole cutting blade

1.apply flex and put the reworking heat in the normal ic mode
2.find a gap to insert the knife in to the ic while applying the hear try to remove the glue layer nicely sideways
3keep in mind that there are copper tracks under the ic dont harm it while removing the ic
its a simple work but there is no vedio to upload with me so search it goodluck

[Wites OM Tesla]

Originally Posted by peeko786

sir how can i remove glued ic?

Try give 500C of heat let me know if work!?

[shaiiskiaev]

do someone know more abut this "low temperature solder" ? its more easy to put a new battery connector and more PFCs when you use low temperature right?
i have tryed to look for it on ebay but its very expensive

[Wites OM Tesla]

Originally Posted by shaiiskiaev

do someone know more abut this "low temperature solder" ? its more easy to put a new battery connector and more PFCs when you use low temperature right?
i have tryed to look for it on ebay but its very expensive

It is very useful to unsolder some connector even reuse it on other fone but i not recommend it to solder back any connector because it will give crack with time pass,so use it only to unsolder!