propellanttech wrote:I reflow and never have had a problem with 402's footprint with reflow.
I saw a reply about tombstoning....but never had one to raise on reflow.
Could you point out the library of the suspect footprints?
James, Dave, et al,
Can you bring me up to speed on 'tombstoning'?
I assume it is where an SMT part tips up while the solder is liquid.
What causes it?
I've recently moved to hot air and solder paste assembly (very low volume, but better than soldering by hand with an iron).
The only problem part I have is a 1206 LED. I suspect I have applied too much paste, and the molten solder floats the part. This is only an issue when the LED dome doesn't sit the right way after the solder sets.
In EAGLE there appears to be different footprints, can I assume these apply to different solder types or solder methods?
For example: C1206 and 1206K (Kemet?). R1206 and 1206W (wave?).
For some parts I've used straight from the EAGLE libs the pads seem too small to apply a soldering iron. Either the part boby covers the pads (SMT trimmer caps) or due to the bulk of the part (large can electrolytics, shielded inductors) they take a lot of hot air to solder at all. For these I prefer to 'convert' the solder paste with the MetCal and not over heat the board with hot air.
Comments Welcome!