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Step 10: Reflowing!

So after ten minutes of pre-heating the board, I begin the hot air reflow. Make sure that the air pressure is at 5 1/2 (thats the dial in the bottom right of the unit). The lowest temperature the unit can go to is 90C, so after I turn it on I wait to time until the actual temperature (bottom number) reaches 90. You always wait for the unit to reach the temperature before you start timing. Note that the griddle is on at 400F for the whole time.

This is the heating profile that I follow (All temperature increases are in 3 deg/sec, which is one press of the up/down button on the unit a second):

- Turn on the unit and wait for it to reach 90C.
     - Hold for 60 seconds
- Increase the temperature to 195C
     - Hold for 60 seconds
- Increase the temperature to 291C
     - Hold for 40 seconds
- Increase the temperature to 350C
     - Hold for 20 seconds
- Increase the temperature to 381C
     - Hold for 20 seconds
- Decrease the temperature to 291C
     -Hold for 10 seconds
- Drop the temperature to 90C as fast as the unit will go.

When it reaches 90C, I turn the unit and the griddle off. At this point, it is incredibly crucial to not touch or move the board. You need to let it sit for at least 15 minutes without being disturbed.

*Another Note* These machines are not exactly the same, my 381C may actually be outputting air at 360C, where yours may be doing 400C. Its very beneficial to get a test board and figure out just how hot you need to go on your machine before the solder melts. This is called a BGA lift, and just follow this profile up to 350C. After that go up by 3 degree increments. Wait ten seconds, and try and lift the chip up with a flathead screwdriver. If it lifts, that's the temperature you need to hit. If not, keep going up until you can lift the chip.
 
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I only own a heat gun that has twelve heat settings on it. Is it okay if I don't use exact temps. I have never done this before, but I am planning on it.
bshi022 years ago
I live in korea and It is nearly impossible to buy below items or alternative for following this repair guide.
Aoyue 968 Reworking Station
-Rework Nozzle #4141
-Modified Presto Griddle

I plan to do traditional soldering way(by hand BGA soldering), instead of doing this reflow process which require many equipments.
Is it possible only to use 30 watt soldering iron for resolering solder joints near or underneath of GPU chipset?
and this traditional soldering can take place of reflowing process?
I'm sorry for my weird English,and thanks any replies in advance.
Anasazi292 years ago
I cant get this to work. I bought all of the exact items. I have about 12 xboxes. I have tried 3 so far and nothing. still RROD. I check the error codes they have and all of them say CPU/GPU overheat. I cant figure out what I'm doing wrong. I even did a test motherboard and lifted the gpu off of one by up'ing the heat to 530.
out of the 3 that I've tried, I have tried each several times. 10 - 15 times total, so far.
I'm going to turn the air flow up and try hotter. and go from there.
Airflow rate makes a huge difference and varies between stations, another reason to just give it to a pro/specialist. Nice tut, but I would use slightly longer times and you make no mention of flux, once you have burnt that out (which might have already happened.. dam unleaded solder) then all the heat in the world wont fix ur box! But if I need to tell you that then you probably should just pay the 50dollars and give it to a pro and make it their problem, plus they should give u a warranty. If you follow this method (and this has to be one of the best ones I've seen) then you might get up to another year or so out of it, if it's done correctly you should NEVER get another RROD ever again! (at least not for 10-20 years by which time ur 3rd DVD drive has died anyways ;-)
billyrawktm3 years ago
tbh 291 and temps like that dont matter u could just set the station u have to 290 because i have aoyue 852a++ station and it only goes up 10oC each time so i just set it to the nearest 10oC
Luongo1233 years ago
Use a microphone stand. It works perfectly
hackerjoe3 years ago
oh by the way did you do a tutorial for the stand for the nozzle ? and also what was the exact setup for the griddle? 1/4 inch plus or minus ?
hackerjoe3 years ago
Wow nice tutorial ---- Just a FYI --- Kohls has the griddle for $18 this week so I picked one up :) I'm ordering a 968 soon from SRA he sells on Ebay and its a little cheaper. Does this unit perform well ? I also asked about getting a nozzle thrown in for $20 to save on shipping. I have a few consoles I'd love to try this on. I have a few stubborn RROD's Have you done any reballing with the 968 I was told the vacuum tool wouldn't lift the CPU/GPU as they are to heavy for it? Thanks
Doxsey4 years ago
Any update on the stand guide? My stand is terrible and I need to build a new one and I am looking for some good advice. Thanks for all that you do!
oxbeast12104 years ago
Hey great guide works perfect  im just wondering if you know of any guides that show how to build or use something else as a holder for the nozzle and handle urs looks great but i cant tell how its set up 
thanks
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