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Cruise Control Brain Solder Reflow... in the oven.

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Old 05-11-2012 | 04:28 PM
  #16  
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Actually most PCBs are soldered in ovens these days. They are just a lot more sophisticated in terms of their temperature control. This process is called 'reflowing' and the ovens are called 'reflow ovens'. Lots of times small engineering labs or those on a super tight schedule will reflow in a large toaster oven and there are folks that make control boxes to get the correct temperature profiles from toaster ovens. You can also do it manually with a thermometer and a toaster oven. The correct temperature profiles are not that hard to produce, but they should be followed as carefully as possible. In addition the melting the plastic cases on the ICS many of the other parts like resistors and capacitors need to preheat before the actual solder melting cycle to get moisture out of the parts and to avoid too much of a thermal shock. So if you don't follow the correct temperature profiles you can crack these parts.

One thing: you should really do this in a dedicated toaster oven and not your kitchen oven. The gasses produced are not something you want in your food. If you must do it in your kitchen oven, please clean it thoroughly afterwards.
Old 05-11-2012 | 04:32 PM
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Reflow soldering is the most common method of manufacturing surface mont boards, and has been for quite some time.

Done properly, it is an excellent way of repairing old boards.

HTH,
-don
Old 05-11-2012 | 04:51 PM
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So if I had a little Toaster oven set to 250-300 degrees this would work ? Im going to have to test this out on some bad pcb's I have sitting around from old Megasquirt projects..
Old 05-11-2012 | 05:42 PM
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I just gotta add this.

I didn't know that "Reset" on the cruise is our "Resume" and I hit it getting off the highway and MAN... that pedal dropped out from under my foot and my Porkenized beast jumped like it was gonna' mount the BMW SUV in front of me. Hoowee!!
Old 05-11-2012 | 06:04 PM
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Yes, absolutely you can reflow in a toaster oven. Google 'reflow toaster oven'.

Here is a good starting link http://www.instructables.com/id/Toas...-Soldering-BGA, although they do not seem to use a pre-heat cycle. The best think about this particular link is that it uses an unmodified toaster oven. Many folks are hacking up their toaster ovens to make them more consistent and more automatic.

Also you can find a ton of videos on youtube.

Here is a temp profile I found Have not checked the specific values, but this is the sort of thing...

4 min. 200 deg. Warm up board and allow temperatures to equalize.
2 min. 325 deg. Bring temperature up to saturation.
30 sec + 450 deg. Temperature raised until solder melts and beads at individual pins, then held for 30 additional seconds.
Tap the oven before cool down...
Old 05-12-2012 | 06:53 AM
  #21  
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My thought was the reflow stuff I had seen, years ago, used IR not hot air, and pretty sure not 100% of the board is populated during reflow. Toaster oven might work better than conventional.

Still

If you have a proper iron I would think fixing only what is broken might be best.

OTOH I used to have a huge American Beauty tin smiths iron that would flow solder about an inch or two away.
Old 05-12-2012 | 08:15 AM
  #22  
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IDK man, hundreads of 8600M GT's fixed by oven reflow can't be wrong.
Old 11-17-2012 | 08:55 PM
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anyone else have any luck with this? or temp setting changes?
Old 11-17-2012 | 10:06 PM
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Originally Posted by 17prospective buyer
A similar thing (like the Xbox ATI/IBM chipsets that tended to run way too hot) is done to reflow the defective 8600M GT graphic cards on 2007/2008 laptops.
hmmmm...ive got a lap top of that vintage with a bad card!
Old 11-18-2012 | 12:36 AM
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All I can say is my CC still works like the speedometer needle is tacked in place.
Old 11-18-2012 | 10:58 AM
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I have a reflow station....I do pc and laptop repairs as a side business (25 years now), and got into repairing PS3 and Xbox...was just starting to learn how to reflow (without much success, yet...) when I had to pack up and move....once I get resettled, perhaps I might try to "flow" some brains????
Old 11-18-2012 | 11:33 AM
  #27  
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well i gave it a shot in the oven. watched the solder "change" as it remelted. some i did with a iron before hand, today we shall see what happens. if this does not work, id love to send out my second brain to get pro fixed..
Old 11-18-2012 | 01:24 PM
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Originally Posted by DanielD
Agreed. Automotive or consumer electronics are not rated to withstand that kind of heat. My guess: it was pure luck..
Yes, I would think so. Many of the components could be damaged or change value, especially capacitors. I know the old spec for commercial radios was -40 to +60 C as operating range. Consumer is much less.
Old 11-18-2012 | 02:00 PM
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understand that through hole components were originally mounted dry on the PCB then put through a Wave Solder machine.

In the solder machine the populated PCBs are on a conveyer and the bottom side of the board passes over a Wave of molten solder (secs in time) and through capillary action the solder is drawn up through the PCB holes and onto the components soldering them in place which instantly cools as soom as the conveyer pulls the PCB out of the machine.

Modern technology uses solder paste and IR ovens.
Old 11-18-2012 | 02:09 PM
  #30  
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well it worked! YAY!


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