I'm super new to soldering. 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?

If you don't care about the PCB, use a blowtorch and pliers to pull the chips like teeth. I've used a regular builders blowtorch a few times, but you can get a modeller's pencil blowtorch that doesn't smoke the room up so much. You can get extraction tweezers with hooked ends for DIL chips, BGA and the ones with pins all the way round can be just slid off when you melt the solder.

 

If you don't care about the PCB, use a blowtorch and pliers to pull the chips like teeth. I've used a regular builders blowtorch a few times, but you can get a modeller's pencil blowtorch that doesn't smoke the room up so much. You can get extraction tweezers with hooked ends for DIL chips, BGA and the ones with pins all the way round can be just slid off when you melt the solder.

LOL. In my younger (and poorer) days, I'd harvest surface mount components off boards by clamping them upside down horizontally, one edge on the table with the rest hanging out over some newspapers spread on the floor. Torch the side pointing up (the bottom) and then give it a good whack when the solder melted. Lots of components popped off. Some were actually usable. My wife at the time would bitch and moan about the smell. It was pretty bad.

 

Torch the side pointing up (the bottom) and then give it a good whack when the solder melted. Lots of components popped off. Some were actually usable.

A similar technique is used in China:

 

use a blowtorch

I've done that!

 

LOL. In my younger (and poorer) days, I'd harvest surface mount components off boards by clamping them upside down horizontally, one edge on the table with the rest hanging out over some newspapers spread on the floor. Torch the side pointing up (the bottom) and then give it a good whack when the solder melted. Lots of components popped off. Some were actually usable. My wife at the time would bitch and moan about the smell. It was pretty bad.

I have a tin labeld; "SMD shakedown".