Re: Philips 42PFL7108K/12 dead
Reflow probably won't last.
Got some of those reflowed fusions since beginning 2019, all failed again within 3 months usually.
First ones I reballed are still running for +/- 1.5y now.
If it fails again and you want to keep it running, (let it) reball.
Some pads are probably oxidated, turned black, whatever not making full contact anymore.
Heath = oxidation. Reflowing it everytime it fails can make the pad contact areas smaller every time (oxidation grows) untill it fails.
Too much uncontrolled heath...
Deusjevoo
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Last Activity: 04-05-2025, 09:48 AM
Joined: 09-29-2010
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Re: GPU common problem
@Duranitron If you "always buy good bga chip with leaded balls already on it" you always buy REFURBISHED BGAs.
New BGAs are lead free only.
Which is why I prefer reballing myself as I know it's an original chip, no risk buying a fake one.Leave a comment:
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Re: GPU common problem
Curious how you do that.
Isn't removing a (underfilled) BGA with CNC to preserve the PCB to accept new or donor chips ?
Destroying the BGA in the process ?
Don't see why a normally lifted BGA wouldn't be usable again?
Doing it for years without problems, no need for CNC, reball it and and runs for years again....Last edited by Deusjevoo; 07-22-2020, 02:17 PM.Leave a comment:
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Re: AMD 3870 VRAM problem?
Your profile is ok, but I'd go a bit slower.
Do you know the history of that card? Has it been reflowed maybe before you bought it?
If a BGA fails it's mostly the solder. Mostly, not saying it'll never be the bumps but that's rather an exception. Was more a problem during transition from lead to lead free period probably.
Reflowing MIGHT fix it but although it was still working that card probably already had bad solder connections. It'll only get worse over time.
Every heat cycle can add to it....Last edited by Deusjevoo; 07-13-2020, 07:07 AM.Leave a comment:
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Re: replacement triac for BGA welder
You can use iced (0c) and boiling (100c) water to verify them....Leave a comment:
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Re: Beginner, practicing to unsolder on a lead free xbox 360 board, it is hell.
Well, at least we know it goes up to 450c... ;-)...Leave a comment:
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Re: Noob - reballing, balling, stencil questions...
((Corrected my name in the quotes, it's DEusjevoo, NOT DuEsjevoo (small detail, but for search function...))
Not saying it won't work but a higher risk for head in pillow errors. (HIP is a weak point that can make temporary contact but fail later or fail from beginning)
This means the solder paste melts, solder of socket melts and they should flow into each other. However, sometimes it doesn't, the solder paste melts, solder ball sits in it on top, doesn't mix, cools down and you get a concave melted solder...Last edited by Deusjevoo; 05-17-2020, 08:22 AM.Leave a comment:
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Re: Noob - reballing, balling, stencil questions...
Too much flux. If this is residue from flux after reballing, leaving the old flux on and then try to "reflow" the balls again it's definitely way too much flux. In BGA Reballing "less is more" definitely applies to flux use.
Also, if your balls attached to the pcb, why would you reflow them again ? Useless imo, unless some didn't align up well. What flux you use?
No matter what rework job you do, preheating will always help. I reball using DH stencils on a small preheater @200-230c...Last edited by Deusjevoo; 05-16-2020, 09:36 AM.Leave a comment:
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Re: GTX 780tI Repair attempt...
That KADA 853B preheater is a small one?
Use your BGA rework station as preheater. Videocards have lots of copper sucking away heat. Use the Quick to remove the ram chips.Leave a comment:
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Re: Panasoniv TH-P42XT50M HDMI doesn't work
@buchman Only seeing it and going for it is risky. Better practice bga reflows/reballs on scrap boards first.
Reflow mostly works only temporarily, often only for a short time. Can be a hit or miss. Reballing it should be a longer term solution.
If you've never done that or don't have the tools for it you can of course try a reflow. Luckily it's a low mass chip, more chance it might work if the pcb doesn't suck away all the heat.
But as diff said, be careful or you can toast the chip.
What hot air...Last edited by Deusjevoo; 04-26-2020, 05:44 PM.Leave a comment:
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Re: Panasoniv TH-P42XT50M HDMI doesn't work
Delete please. (Got an error resulting in a double post)Last edited by Deusjevoo; 04-26-2020, 11:50 AM.Leave a comment:
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Re: Panasoniv TH-P42XT50M HDMI doesn't work
What stuff do you have?
If not the correct one, better don't try yourself if you want to salvage it.
Surely if it's the "first time you see an elevated IC..."...Leave a comment:
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Re: How to clean oxidation from BGA pads?
@spider1211 Think that Felder Lotferr is for plumbing or metal soldering, not for electronics. Wouldn't use it for that.Leave a comment:
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Re: How to clean oxidation from BGA pads?
To clean pads use a GEL FLUX, not liquid. Liquid evaporates and looses activation too fast.
To get rid of that oxidation higher activation (gel) flux types can give better results but they have to be cleaned off thoroughly as they're more acidic.
Reason for the the dark pads can also be a bad finishing, hard to fix sometimes.
But using gel flux and touching it with some solder, even rubbing it slightly but don't sratch, can help. Or soak a solder wick with solder, add gel flux to the pcb and go over it with soaked solder...Last edited by Deusjevoo; 04-04-2020, 05:18 AM.Leave a comment:
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Re: recommend: a hot air gun for gpu reflow?
Good luck with a hair dryer trying to get lead free solder to melt.
Really wonder how long those hair dryer "reflows" really last?
Like diff just mentioned, if the chip itself is bad, better replace it.
But even those nVidia chips can work for years again after a reflow or reball, and I do speak of experience with devices working over 4 year again after a reflow.
Not bad I guess?
Ofcourse, I talk about a REAL REFLOW using a bga rework station and a controlled process.
And yes,...Last edited by Deusjevoo; 04-30-2017, 04:14 AM.Leave a comment:
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Re: recommend: a hot air gun for gpu reflow?
Those are unsuited for GPU BGA rework.
To small preheater, top heater is a bulb, low power.
Waste of money....Last edited by Deusjevoo; 04-29-2017, 04:54 AM.Leave a comment:
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Re: Smd rework - Solder balls squeeze out
What you use? Hot air? IR? Rework station? Do you preheat?
Photo of setup and pcb/underfilled chip?...Leave a comment:
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Re: Yet another BGA machine dream
Curious for those tapered stencils.
Tapered are for use with solder paste normally.
Like the one used here:
[url]https://www.youtube.com/watch?v=MqRT6KaMubk[/url]
All reball stencills I have seen are just straight holes.Re: Yet another BGA machine dream<br... just straightLast edited by Deusjevoo; 08-09-2014, 05:06 PM.Leave a comment:
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Re: IR rework station
Hope not to late.
But if you buy a jovy, go for the RE-8500.
The 7500 is ok for small stuff like cellphones etc, it has a to small preheater for larger PBCs....Leave a comment:
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Re: Looking for recommendations on IR rework station
If you're a DIYer you can build an IR machine easily.
Or, might be a faster solution, get the cheapest IR Pro, recable and mod it if needed.
Depends on what heaters it uses but mostly Chinese crap, even the Bauer.
You might end up with a machine beating even some very expensive ones.
(Apart from the optics or auto lift/replace of BGA)
Can do anything with my old modded IR Pro as good as a high end machine can.
Was thinking about getting a hot air machine but don't see the need to switch...Last edited by Deusjevoo; 07-21-2013, 12:35 PM.Leave a comment:
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