# Safe temperature for desoldering SMD components w/ hot-air rework gun?

What is a reasonably safe temperature to use for desoldering SMD components using a hot-air rework gun? I have a new-to-me rework station from Xytronic and the documentation clearly assumes you know what you're doing… It tells you what temperature range the gun is capable of, but has nothing to say about where you should be setting it.

Also, I was surprised by how little air pressure the unit generates even when the AIR setting is set to max (99). Is this normal?

My one test so far was to desolder a random surface-mount IC package from a piece of electronic salvage I had lying around (kept for exactly this purpose). I tried to step up the temperature slowly, but I got all the way to 400 degrees Celsius before the chip seemed to suddenly be floating free. I never did see any visible change in the solder… (But perhaps that's just my eyesight.)

I am concerned that at that temperature any component that I can get off a board might be damaged by the heat.

• Double check if the temperature is Celsius or Fahrenheit. 400 C is really hot. Feb 3, 2012 at 22:19
• This was a commercially manufactured board, so I'm pretty sure it was lead-free solder. And yes, it was 400 C… Over 700 F! The Xytronic gun tops out at 480 C. Feb 4, 2012 at 0:24

If you just bought it (or replaced the element), some stations will need calibration. (ALWAYS check). If your unit has potentiometers on the front use a non inductive screwdriver. Otherwise look for a calibration mode. Search: "rework station calibration" or "rework station calibration mode" Harbor Freight tools has a infra red temperature probe for $20.00. -Should do the trick. When I unboxed mine, it was 100c out. -e Pre-heating at 200 degrees Celsius for 1min, then raise temperature to 400 degrees Celsius to heat for 20sec. You can use a thermal couple to monitor the temperature. preheat your pcb to 150c. Use Chipquick alloy or Zephertronics Lo melt. Apply flux, lomelt let sit for about 4 mins then lift the chip off the pcb. Use flux and a swab to gather and remove the leftover lomelt • Have fun trying to buy less than$100 of that at a time :) Mar 20, 2018 at 5:25