thought id start by posting my achi rework process and profile for anyone to use/test/laugh at lol
"what you want is the board bolted to the support jig and resting on the magnetic rails. make sure the bottom tc is touching the bottom of the board but not touching any components under there. set the bottom temp to 230C, high i know but this takes into account the air temp thats being radiated off the plates and its what ive always used and its been fine. you may find its too high for your machine but its all trial and error.
my profile is:
0.00/0/180
1.00/190/30
1.00/200/30
1.00/210/30
1.00/225/40
-0.01/0/0
if you run that, what it will do is run the bottom heater for 180 seconds before the top heat kicks in at stage 2. what you want to watch is the sv and pv. sv is target temp and pv is actual temp. the time in the steps is how long the top heat will dwell at this temp so for stage 2 it will dwell at 190 for 30 seconds. at the end of the 30 seconds you want the sv and pv to be within 1-2C of each other so keep your eye on it and if say the sv is 190 and at the end of the dwell the pv is 185 then youll need to tweak the profile to extend the dwell until they match. keep playing with the profile and use the same board but obviously allow it to totally cool between runs. the 1.00 is the ramp rate which means 1C/second.
i have the top heater lowered so its 2.5cm above the board so i just marked in marker pen where 2.5 is so i know everytime.
once the alarm goes you want topside temps to be 220-225 and you should be able to see the solder balls have melted. i then allow the alarm to finish but keep your eye on the temp and if it begins to go above 228 then lift the top heat slightly, then wait 20 seconds and lift the top heat all the way. then wait a further 20 secoonds and swing the top heat out of the way and turn on the fan switch which will cool the top heating plate. i then leave it to cool naturally until about 140C and then swicth on the cooling swicth which should cool the board fast.
the reason i use this process is removing the top heat too fast can cause shock to the gpu causing it to popcorn and applying the coolers at too high a temp can lead to board warp."
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you can also test the resistance across c5d5 whilst the gpu is still attached as shown in this pic.
i take no credit for this info, just reposting. i got this info from xbox experts so credit to them.
http://xbox-experts.co.uk/tutorial/h...-cpu-is-burnt/
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you need to devise a profile with a final temp of about 197C for a good reattach. always works for me but its just a case of tweaking your lift profile so the final step is lower.
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It's worth pointing out......a lot of guys who are just startting out ask about reflow profiles....I know when I started it seemed like there was some mystical method used that only pros knew about and nobody would let on.....lol
so they key ingredients guys as far as I have found on my journey:
-the melting temp of lead-free solder (original solderballs on m$ GPUs) 217*-225*
-the melting temp of leaded solder (preballed replacement GPU's) ABOUT 183-193*
-the bottom heater (preheater) is the most important bit of kit...this does approx 2/3 of the heating work...hence the 180* recommendation in Flash's profile.
heating needs to be done gently, and EVENLY......cool down needs to be gradual also.....
just a bit of info for peeps thinking of starting out, as it all seems very daunting at the start.
I have successfully done reflows on EVERY console so far with no returns, but we're only talking 30-40....
I always start with a reflow after checking the secondary error code, as there is nothing to lose...then would move on to a reball afterwards
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Flux is key when doing reflows/reballs.
Don't buy crappy stuff on fleabay. Most of it has been diluted with IPA.
http://www.insatinternational.com/pr...&product_id=84
This is the stuff to get - I can't sing its praises more than I am. It's the mutts nuts. I've attached a pic of a chip lift after applying this stuff under the chip. See how clean it is??
I think you can get a discount from Jimmy if you mention T-X but you'll need to check first - Flash might know more about this than me as I got this on his recommendation
From the above link:-
In wave soldering the flux is either sprayed or foamed and applied to the PCB and the total exposure time to soldering temperatures is around 10 seconds.
When you reflow a games console or a notebook the time-temperature profile is typically 4 1/2 minutes. A flux designed for wave soldering is really meant for conveyor belt soldering of PCBs and not reworking or reflowing PCBs.
Most liquid fluxes would simply evaporate away during the running of a reflow profile, possibly allowing the solder joints to be re-oxidated which would result in early failure due to having low solids content. (around 4% by wt)
Our flux has more than 6 times this amount to provide a high solids content flux. Mildly active acids in the flux remove the oxides from the metal surfaces to be soldered. The solids in the flux are responsible for creating an oxygen barrier to prevent the metal surfaces becoming oxidated again at near soldering temperatures. Our flux is designed to provide not only an oxygen barrier but also a moisture barrier over the soldered areas.
BGA failures could be due to:
1. Cracked intermetallic bond.(Thermal cycling)
2. Black pad syndrome (oxidation)
3. Flux residues becoming conductive (moisture)
The list can be a lot longer but in our view the above are probably the most important that cause BGA failure.
Our flux is the only liquid flux that addresses all the issues that cause early failure of reflowed games consoles and notebooks or whatever else.
We are confident that if any flux could single handedly solve the problem of reflowing, than this is the one. This is a brave statement to make, but that is how excited we are about this flux. We could run tests for the next couple of years to prove our point but feel confident if this doesn't work, then nothing will and give up on the idea of reflowing and instead just reball or replace the BGA with a new one.
This is a test for reflowing. Most console repair shops have given up on the idea of reflowing due to high numbers of failure in a matter of weeks or a few months at best.
As they say in the rework industry, a flux can be your best friend or your worst enemy. We think our flux will be your best friend.
The
RMA - Rosin Mildly Activated ROL0
Meets IPC-SF-818 Standard for the lowest flux residue corrosivity and highest surface resistance category.
Maximum achievable RMA activity to remove metal oxides completely.
High solids content to prevent re-oxidation at elevated soldering temperatures. Forms both oxygen and moisture barrier under the BGA.
Completely non-corrosive and non-conductive. Our flux starts to activate from about 95 deg C and has a wide temperature window to well above 260 deg C to see through the profile reflowing process to the end with no risk of re-oxidation. No corrosivity or conductivity issues due being a no-clean flux.
Some people may find it too tacky but that is a small price to pay since the natural rosin is a very tacky substance but unlike synthetic resins, it stands up to high temperatures and in our opinion the best choice for reliable fluxing.
We recommend the following times and temperatures for your reflow process for all lead-free equipment.
1. Preheat the PCB using the bottom heater of your rework machine from room temperature (25 deg C) to 150 deg C in about 2 minutes. The rate of temperature rise should not exceed 2 deg per second in our view.
2. Soak the PCB for 90 seconds and allow the PCB temperature to rise to 185 deg C at the end of this time. This means that the rate of temperature rise is slowed right down to allow the flux to remove the oxides and even out the PCB temperature, readying it for the reflow process. Use the bottom heater to raise the PCB temperature as much as possible which will reduce the amount of heat applied to the BGA directly, therefore minimising heat related damage to the BGA itself. If the final soak temperature of 185 deg C cannot be reached in the allocated time, then use the top heater as well to assist the bottom heater.
3. Reflowing stage demands that the temperature of the PCB is raised to well over 217 deg C (melting point of lead-free solder) and we suggest 235 deg C as the maximum reflow temperature. The temperature ramp rate should be increased so that the maximum can be reached in 30-45 seconds after the end of the soak stage. Allow a few seconds at the maximum reflow temperature and then switch the top and bottom heaters off.
4. Allow the PCB to cool back to room temperature.
If you reflow leaded solder equipment then you may use 205 deg C or 220 deg C as your maximum reflow temperatures.
When reflowing PS3 or XBox360, it is important to use anti-warp jigs as both items suffer from PCB warping when heated.
Our flux is manufactured for us by a top US flux manufacturer.
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yes mate attach a note with your order telling him youre off tx for a 10% discount.
just a little something i arranged for you guys.
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http://forums.xbox-scene.com/index.php?showtopic=484726
http://xbox-experts.com/errorcodes.php
Are links permitted? kill em if not but here are a couple places to start
youre using the blue jig, theyre ****e.
also i use the aoyue to heat the chip. once theyve set if theyre not all on their pads (which they normally are if you use amtech 4300) then put a few spots of jimmys super flux on and reheat and the balls will move to the pads.
different amtech is different, 4300 is the best, the thinnest layer will do.
i use the aoyue on 430C, air flow 3 and one of the smaller square nozzles
use amtech 4300 for reballing and insat super flux for reflows
I don't know if this has been mentioned previously in this thread - if it has I have no doubt Flash or Martin will delete this lol
but it's really important for anyone starting out to have a jig - board warping is a massive problem - I have also found that the humidity affects the "warping factor" - that's why I find M.E.K. in prep essential
I was bored - thought I'd throw this on the thread lol
EDIT: - make sure when purchasing a jig, to get a steel one, not aluminium - they warp eventually too due to the heat strain......there are guys one here supplying these - worth investing
not the best quality as ive got limited light due to the glare but youll get a sense of what i alu tape off and how i attach the tc and also how high the achi top heater is away.
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Lads watch yourself's with the insat international liquid flux.
It brilliant stuff but the rosin is really bad for you
http://www.hse.gov.uk/pubns/indg249.pdf
I've stopped using it since I started getting these symptoms described here.
I'd advise anyone using this stuff to have some serious respirator setup.
Your health is worth alot more than the money you get from fixing a few xboxs.
Just a heads up