After removal of glued UEM and glued uem removal video guide

[Raheeeeb]

[QUOTE=JulesJ]Hi Guys,i've replaced alot of UEM Glued(or underfilled as i call it).ive been very successfull with this and maybe this tip could help!
Tools:Flux,Straight fine tpped tweezer and Hot air Station
1:Heat Uem very hot,aplying flux while heating
2:Gently lift Uem while heating using the tweezer(the UEM should peel off,if using enough flux you would reduce the chances of damage to the pcb.There should be quite a bit of resin left on pcb,This i remove with alot of concentration and focus in so that i do not damage any tracks)
3:add flux to pcb(UEM AREA)
4:while heating gently chip away access resin from pcb (not alot of pressure needed."LIKE GOLF",letthe tools do the work!
5:This process takes about 15-20 minutes,but well worth the time spent.

Hope this helps.
Best Regards!
thank you for your co operation
i only want to add the doctor knief and the solder wick to the tools
why?
becuse when you remove the uem you have to clean the pcb
1- use solder wick to remove all the solder balls left in the pcb
2-after you have a little glue left
3-use the doctor knief to remove all the glue from pcb
4-you must use small air and middle heat and small nozzel when you clean pcb only to avoid heat image reach any around the area you clean

thank you

best regards.
raheeeb

[Raheeeeb]

@pintphones
thank you for your information hope to keep share your experince with all ppl here

[ZetMen]

i try my solution with drill uem when i see the balls i stop i start with hot air i clean and haft hour i have clean mainboard and ready to put the new uem

[DMD]

@ Raheeeeb

I normally grind off the UEM until Its just the balls and underfill then put a small square piece of cloth soaked in BGA adhesive remover then leave in a sealed packet till the following morning then the underfill can be peeled off then you remove the solder balls the normal way with desolder wick/mop

Regards D.

[Raheeeeb]

Originally Posted by DMD

@ Raheeeeb

I normally grind off the UEM until Its just the balls and underfill then put a small square piece of cloth soaked in BGA adhesive remover then leave in a sealed packet till the following morning then the underfill can be peeled off then you remove the solder balls the normal way with desolder wick/mop

Regards D.

for more help post here what the type of this remover name how much where all ppl can find it ..

br.,

[aboud]

i`ve tried to remove the uem from 1100 ,but after a while from heating it the cpu rebolled the solder.
i spoiled 5 phones in this method it can`t stand heat.

[Raheeeeb]

Originally Posted by aboud

i`ve tried to remove the uem from 1100 ,but after a while from heating it the cpu rebolled the solder.
i spoiled 5 phones in this method it can`t stand heat.

you have to remove the cpu and replace another one
phones ll work again

br.,

[aboud]

but it will be dubble work,i`m trying to make business and money not pay money

[DMD]

@ Raheeeb

Try www.tele-way.com
it will direct you to one-stop factory shop (not sure of the url)

Regards D.

[valley-side]

please can u show picture on chageing hager or cobba

[Fonetec]

Can somebody explain the process of re-balling i.c and the method for putting i.c. back into pcb pls.

This is my process

1. after removed ccont i clean the i.c up with solder wick
2. clean pcb with care and remove all old solder
3. I get my solder balls in the stencil in the right place
4. i apply the solder paste to the ccont i.cso the underside is all covered
5. I get ccont i.c and now place into postion over the stencil and drop it into place making sure the chip is in the right place.
6. after leaving for a few minutes for the paste to dry a bit i pull the i.c from the stencil, the ccont i.c now is reballed the solder paste is holding the new balls to the i.c.

ok this is now where i get problems

7. I put the ccont i.c. into place on the board, but when i apply heat to it with hot air machine on the lowest setting the balls under the i.c go every where and do not stick


please, please can somebody help me and tell me where i am going wrong ?
maybe i am re-balling the i.c in the wrong way ????


thanks

[Raheeeeb]

1- you must heat the solder cream befor you remove teh stencil off the ic
2- you must heat the balles after you make it and remove teh stencil once again

thanks ..

br.,

[Fonetec]

@ raheeeeb

Don't understand what i have to do please explain in more detail please ?

[Raheeeeb]

6. after leaving for a few minutes for the paste to dry a bit i pull the i.c from the stencil, the ccont i.c now is reballed the solder paste is holding the new balls to the i.c.
thats what you said... no you must heat the cream befor you puul the ic up till yu have riged balls under ic.



7. I put the ccont i.c. into place on the board, but when i apply heat to it with hot air machine on the lowest setting the balls under the i.c go every where and do not stick
thats also what you said...and you must never apply ic with solder cream to teh board
becuse if the service centers do becuse they use heat oven theroy so the balls become reged befor any contacts with pins on board also but not scen..

[Fonetec]

@ Raheeeeb


AHHH, now i understand, thank-you very much i will try !!!!!