Rapid Desoldering?

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TurboSuper
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Sat May 12, 2007 5:34 pm

Alright, so I've come to realize that old CRTs make for great electrical component "farms". I find 15" monitors all the time, and they're bristling with all kinds of components inside.

Now...getting those components out is a different story, and thats why i'm posting here.

Desoldering with an iron takes a fairly long time, so i've been looking for an easier method.

So far heating an area with a torch and pulling the components out quickly with pliers seems to work. I was wondering if there was a better way that doesn't heat up the components as much.

I know that a few of you are real electronics pros, so I wanted to know what your favourite method is.

Thanks!
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joannaardway
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Sat May 12, 2007 5:39 pm

If it were me, I'd just use a much more powerful soldering iron, say for example, a 120W butane-powered soldering iron, coupled with a proper solder sucker.

That would work quite well.
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Hotwired
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Sat May 12, 2007 5:44 pm

Waitaminute.

YOU'RE DESOLDERING WITH A BLOWTORCH?

I'm not surprised you're worried about toasting them.

Soldering iron. Pliers. Small flat screwdriver.

Put some light tension on the component to be removed with pliers/screwdriver levering it up from the board. Touch soldered legs of component to melt the solder on the other side and the component will come free.

If theres more than two legs you have to keep applying tension with the screwdriver or pliers and touch each soldered leg in turn to inch the component out.

I often use that to extract small 6 pin transformers which lose their legs if you put too much force on them.
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frankrede
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Sat May 12, 2007 6:56 pm

why not get the cold heat from radioshack it heats up in less than a second.and is wireless
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GalFisk
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Sun May 13, 2007 4:11 am

And from what I've heard, it kinda sucks.
Soldering iron with a clean tip, desoldering pump, flathead screwdriver and pliers work well, as others have commented. There are specialty desoldering tools to remove ICs and desoldering irons with built-in tin pumps, but those are really expensive.
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MrCrowley
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Sun May 13, 2007 4:27 am

What is worth getting from a 17" CRT I have? Or should I just blow it to bits?
GalFisk
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Sun May 13, 2007 9:35 am

And high voltage caps and diodes, high wattage resistors, power transistors, and other assorted stuff.
Kenny_McCormic
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Sun May 13, 2007 11:06 am

turn the board over and apply heat with a heatgun it wont toast em seing as much more delicate smt boards are made by putting the boards in an oven until the solder melts
TurboSuper
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Sun May 13, 2007 2:31 pm

I used to have a ColdHeat...and it sucked. I know how to efficiently remove individual components, I was wondering if there was a good method to clear the solder (or loosen) off many of them at once.

Kenny has the right idea, I actually read soemwhere that you can put the board in a toaster for a couple of seconds. Mabye I can get a some sort of diffuser for the torch to turn it into a heat gun?

And lastly...i'm using a propane torch, in case some of you thought it was acetylene or soemthing crazy like that :p
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GalFisk
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Mon May 14, 2007 3:48 am

If you can melt a lot of solder points at once (by whatever method), you can just hit the PCB agains something solid and the liquid solder will fall off. Beware of splatter.
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Mon May 14, 2007 10:47 am

I find that a blowgun is very handy when desoldering. Heat the joint with the soldering iron (or blow torch :p) than blast the molten solder away with the blowgun. The blast of air also helps to cool off the component. For me it works much better than a solder sucker or desoldering braid.

Careful of the flying drops of molten solder!

Don't use this method to repair a board. You never know where the drop of solder is going to end up.
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Mon May 14, 2007 11:03 am

Take a 10D nail and some pliers and use your torch to heat the nail up till it is bright red/yellow and use that, but just becarefully not to melt anything else.
TurboSuper
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Mon May 14, 2007 5:47 pm

Thanks for the replies so far guys. So far i've decided to stick with my method of heating the area with the torch and pulling the individual componets out with pliers. I may try that blowgun method though.
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spudzinger
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Mon May 14, 2007 6:02 pm

Ok, WTF does CRT stand for I am braindead today. Second, if its a monitor or screen I know I can't stop people from doing it, but be careful they have nasty stuff inside the tube. ANd second when your done with you debauchery, find an electronics recycling center or day and give them the extra stuff. A rant from you friendly hippy/tree hugger
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