Saturday, 22 November 2014 00:00

My BGA Notes

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These are my notes on BGA reflowing and some electronic notes

  • well tip, chisel tip - these are the best for SMD attaching as per EVVblog
  • melting point leaded 183c,lead free 217c - read V3 scotle Document Pg44
  • met full melt, 200/235 reflow occurs
  • moisture in board 15 mins 150c - read V3 scotle Document Pg48
  • set the soldering iron to 400 for wiping solder balls etc..
  • 195 - leaded solder meltin
    225 - leadded melting point
  • on other video 26.00 johnny tells you where to get his profile from scotle ir-360 queiries @ bgamods.com, http://bgamods.com/forum/viewtopic.php?t=575
  • about scotle software: the software is designed to take the reading from the external tc only when using the ir360 pro.
  • Cooling: Hi Karl / Anybody. I'm back working on my IR360 Pro and have a question.
    Q: What is the best way to use the Cooling and IR Cooling fans on the IR360Pro. (don't want to switch them on too soon and damage the board, and don't want to leave it too late and damage the plates)
    A: coleman (bgamods moderator) I swing the top heater out of the way at 200C and switch fan on for that and then turn on bottom fans when board hits 140C
  • How to build a profile (from BGAMods Forum)
    Q: what way the do you create a profile with a three zone machine ? (jaymbyrne)
    A: The principal is still exactly the same as i never run an actual profile with the lower HR. i just have it set to the same temp as the lower IR and have it running constant so both lower IR and HR should heat at the same rate to give a nice even preheat. ive posted an example profile for ivan but ill do a quick guide tomorrow AM and get it upped in this section.(bgamods) JonnuGunz has a better method.

  • Basic Soldering Lesson 1 - "Solder & Flux"  - http://www.youtube.com/watch?v=vIT4ra6Mo0s05.26 - show different solder meliting points
  • For the ball re-attach (i think this is johhnygunz advice)

    - 1 profile 1.0/190/1000 and just watches them manually (this is for lead free)
    - most will reattach from 80c but when using the machine cold it can go all the way up to 180/190
    - note all bottom heaters are set to off HR (hr = heat radiation ?)

Scotle IR360 Pro V1] Xbox PHAT GPU Reball - Walkthrough

https://www.youtube.com/watch?v=teFwYPRgp5s

  • what is MEK  (cleaning fluid) (it is methyl ethyle ketone, a strong organic solvent, from ebay)
  • people use Q tips
  • get captopn tape and dispenser, better than aluminuim? heat resistant, aluminium tape reflectecs
  • can pull aluminuim tape off at 75 - 80c and leave no residue
  • put the probe right next to the chip but not touching it

  • using RMA 218-kingbo flux for putting around the rim of the chip before lifting, he is quite liberal, bead all the way around it

  • multimeter is used for TC display

14:33

  • lower air adjustment flow is  is set at 4, close to board, 1-2 cm, temp is set to 225c (permanent setting)
  • lower plates set to 225
  • using medical sicors to hold board down

17.03

  • upper ir head height lower possibly 30mm
  • scotle TC might be off 5-8c cooler
  • he makes sure the chip is in the middle of the IR top heater, using the angled tooth pick

18.57

  • he starts the program and you can see the TC he put down earlier (the one on the multimeter
  • target temp is about 225?

21.15

  • heat sink off, profile off, ir cool on

21.25

  • he starts to clean the board up whilst it is still on the machine, profile finished

23.55

  • he is using a cheap angle iron and solder braid to clean off the pads
  • he turns the lower air flow  right down because the air is colder and is hindering the cleanup process
  • thinnner wider wick is better

30.33

  • now the flux is dry he is using the weired sponge thing to clean it of the chip site (painting tool)
  • cleaning site with q tips and MEK
  • 2-3 passes at most, 1 is better for cleaning the pads


38.00

  • preping the top ir for reballing the chip
  • he uses pressboard/cedar wood to cover the bottom nozzle
  • 2 ways to attach the balls to the chip, 1) wand method (hot air stick) (2) this ir methos, or (3) hot plate
  • ir head about 3cm above the would
  • profile 190 degree a second
  • by the time it reaches mid 80s they ae pretty much all attached
  • does not seem to use the inbuilt probe

40.11

  • reballing the chip
  • recommends the scotle angled/diagle rework gig
  • kingbow flux again to clena the chip
  • clean tip
  • typically use a different iron (hako from freds electronics, big wattage)
  • take solder of the chip
  • clean chip
  • changes iron again to a dirty looking one/ angled iron (cheap iron) for using solder braid

51.25

  • grabs tacky flux (superior tacky flux 8600 RMA water soluable) for sticking balls down

52.30

  • mwntiones about using to much flux
  • now pours balls in

56.23

  • back to machine for ball reattachemnt via top ir
  • get the probe close to the chip, it isnot touching the wood

58.29

  • tight shot of process
  • make sure you turn off your bottom plates
  • lower nosel turned off (0 and wood over the top)
  • if you like you can use you second probe (againn not touching chip)
  • once the balls have attached move it to on top of an xbox heat sink, cools the chip in 10 seconds
  • his balls bonded about 130c
  • balls can attach about 80c

101.32

  • he says the balls already look attached
  • scotle says 130c and his other TC says 93c
  • when the machine is totally cool you might find you have to go all the way up to 185c/190c
  • but once your TC says around 175/180c keep an eye on the balls, get right down and look at them
  • flux can smoek a little
  • balls reattached at 190c

103.30

  • shows how balls that did not attach can be fixed with a hot air wand 430F - 221C air speed .06 or all the way down

107.28

  • test balls are seated correctely

108.18

  • back at scotle
  • attaching sissors to prevent board lifting up

110.50

  • starting board prep

115.00

  • setting bottom plates back to 225c
  • looking for temperatures of 190c

115.72

  • profile start
  • looking for temperatures of 190c/195
  • temperature hit
  • ir cooler on
  • this guy says he does not put the cooler on until 100c because of shock to the board (he is not sure about this)
  • let cool down
  • dont put cooler on until board has cooled down to 100

117.18

  • 37c tempaerature
  • now start pulling tape off at 37c, this prevents residue from the tape
  • clean chip area if needed

120.16

  • board removed from scotle
  • turn lower cooler off
  • done

Notes From Comments

  • Q: what kind of solder are you using? Is it the low melt 50/32/18? or just regular rosin core for electronics? (im speaking of the wire and not the solder balls.)?
    A: I'm using? MG Chemicals 63/37 Rosin core that I picked up at Fry's Electronics. It's the largest diameter for just pooling it for desoldering.(XJonnyGunsX Youtube comments)
  • never spread thermal paste with? your finger at all. in fact, dont spread it anyway since it leaves air bubbles. the best way is just to leave the pea and put the heatsink on.
  • Q: Hi jonny. Great video mate. just getting into this myself. got a couple of questions if you could help me out. what temp was your soldering? iron at when cleaning the pads on both board and chip? also did you say reball with leaded solder? Thanks
    A: Thank you, sir! Appreciate the kind words. I have my Hakko FX-888D set to 755, which is just above 400 Celsius. I also use a chisel tup to transfer as much heat, as quick as possible, over to the solder wick. Yes, it is best to use leaded solder. That is all I use. It works out so much better. Thank you again! Best of luck with everything. It's such a great learning experience with doing this type of work!? (XJonnyGunsX Youtube comments)
  • Q: When you used the aoyue to heat the balls on the? chip, did you say 430 Celsius??
    A: I must have been off my rocker? when I said that. It's 430 Fahrenheit, which is 221 Celsius. Sorry about the confusion there! :] I will correct this, via annotation. (XJonnyGunsX Youtube comments)
Read 812 times Last modified on Saturday, 22 November 2014 22:03