what temps do production boards melt @? going to attempt some smt stencil based board making and didn’t want to melt the board if at all possible 
It’s well below the temperature used for soldering, so you don’t need to worry about it. They char, rather than melt, anyway, when overheated.
It does depend on what the board material is. For Glass-Epoxy boards they get quite soft, think chewing gum, at 185°C. They are fine at 125°C.
hoe can i tell what the material is?
Ask the board supplier? It’s probably FR4.
Really? I've heated boards over that temperature a bunch of times and never noticed any such softening. As Leon indicated, boards tend to char rather than melt...waltr:
It does depend on what the board material is. For Glass-Epoxy boards they get quite soft, think chewing gum, at 185°C. They are fine at 125°C.
Char and delaminate!MichaelN:
Really? I've heated boards over that temperature a bunch of times and never noticed any such softening. As Leon indicated, boards tend to char rather than melt...waltr:
It does depend on what the board material is. For Glass-Epoxy boards they get quite soft, think chewing gum, at 185°C. They are fine at 125°C.
Charred PCB might just be my least favorite smell in the world. Truly awful!
NleahciM:
Charred PCB might just be my least favorite smell in the world. Truly awful!
That and burned up resistors.
None of that comes close to a selenium rectifier…
/mike
i should also note that this board has the green laminate layer on it…not sure if that is the correctly term, but only exposed metal pads on the boards are those that are suppose to be soldered to - mostly smd but some th, does that laminate layer lower the melting temp, possibly of that layer alone? i don’t want to melt off that layer either.
tia,
bob
That would be the soldermask; it should be just as heat resistant as the resin in the fiberglass board itself.bob332:
i should also note that this board has the green laminate layer on it…