Desoldering question

[larry109]

I'm super new to soldering and want to get into building PCs... I just want to get the basics down at first. I picked up a temp-controlled hot air gun and iron station, some wick, lead, flux, desoldering pump, tweezers, etc... I got a few junk modems laying around so i decided to test out and try to desolder the chips.

Looks like a bunch of 8-pin EEPROM chips on them. I added some flux to the legs, set the temp to 350 celcius on the hot air gun, circled around the chip for about 5-10 seconds and the chip easily slid off. But on a different modem, I could not get the EEPROM chip off for the life of me. Had the hot air going for 3-5 minutes, even raised the temp to 400 and it just wouldn't budge.

Is there some sort of special solder on this modem that makes it nearly impossible to get the chip off? Is there a better technique?

 

[||Console||]

First stuff could have been solder paste . Second could be normal or silver .

 

[Alaric]

More recent solder (RoHS compliant) melts at about 450F. A solder sucker is helpful, too. Some chips with a lot of pins make it almost impossible to get all the solder liquid at once and long enough to pull it from the PCB.

 

[RJ88]

More recent solder (RoHS compliant) melts at about 450F. A solder sucker is helpful, too. Some chips with a lot of pins make it almost impossible to get all the solder liquid at once and long enough to pull it from the PCB.

Yeah there's no way you'll get it if can't get every pin at the same time...it won't budge...really rigged stuff like really really hot tip and wrap some fine wire in the shape of it stuff, maybeeeee.

 

[JrClocker]

If you are not interested in saving the chip you are taking off, do the following:

1. Soldering iron with a small enough tip for the chip pins, and a small pair of tweezers
2. Put a small amount of solder on the tip of the iron (helps with conducting the heat better)
3. Place the soldering iron on 1 pin of the chip until the solder flows
4. "Lift" the pin by slowly bending it up
5. Repeat for the other pins

Once you master this technique, I can explain a faster way with solder wick!