Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


300 degrees C enough for LF?

Views: 2361


afm

#52908

300 degrees C enough for LF? | 17 December, 2007

If an oven is marked with a maximum temperature of 300 degrees C, can it be used for LF? Thanks for your help.

reply »

#52913

300 degrees C enough for LF? | 17 December, 2007

The oven's maximum rating isn't really a good indicator as to whether or not it's good for LF.

The real question is can the oven get your board up to the liquidous temperature of the lead free solder that you're using.

So, an oven that has a max temp of 300 may be able to do the job for you.

cheers ..rob

reply »

#52928

300 degrees C enough for LF? | 17 December, 2007

In addition to what robqd3 said, just because you can set your oven to 300� C doesn't mean that (a) it's providing 300� C air, or (b) that your oven will survive the temperatures required to reflow your boards properly.

Confirming (a) does mean profiling. As to (b), if you can run your conveyor slow enough to reach the desired temperatures on your assembly, AND get the right profile (questionable, depending on the number of zones you have to work with) without running the heaters at maximum output, maybe you'll get away with it. Bearings on the blowers are probably the most suspect part.

reply »

#52937

300 degrees C enough for LF? | 17 December, 2007

Have to agree with Steve. PROFILE PROFILE PROFILE It's the ONLY way with lead free. Think about it for a second...a process window about 1/3 the range of SnPb (assuming a 250 degree C max component temp) and you wind up with a fairly small target to hit. OH YEA..don't forget, the days of profiling with an unpopulated board are gone forever (until someone comes to their senses on LF at least!)If you use this method, your job security may be very low!

reply »

Facility Closure

BGA Rework Services