Electronics Forum | Thu Feb 10 09:42:42 EST 2011 | davef
Some solder paste formulations can be frozen with no effect. Other formulations ... not so much. Can you compare this questionable solder paste with 'known good' paste of this part number in a structured test?
Electronics Forum | Wed Mar 14 19:32:04 EDT 2012 | swag
You're not clear if you intend to reclaim and re-use the paste from the stencil or not. If not, then you should go to cartridges with an air gun or modify a caulking gun for dispensing paste from cartridges. The paste will last a long time.
Electronics Forum | Fri Aug 03 15:45:51 EDT 2012 | davef
I agree with Ka. I can't think of a solder paste supplier that doesn't tell you to let your paste come to room temperature before putting the paste on the stencil.
Electronics Forum | Mon Dec 17 08:34:58 EST 2012 | emeto
I would scrap it. As you said part of it is going to be old paste. All manufacturers don't recommend mixing old with new paste because you change the rheology of the paste.
Electronics Forum | Fri Mar 08 03:21:18 EST 2013 | sdhmuni12
Can a ROHS PCB with ROHS solder paste can be cleaned in same basin/sink when Non-ROHS solder paste PCB are cleaned? Any detail procedure or cleaning technics for NON ROHS Solder Paste PCB VS ROHS Solder based PCB?
Electronics Forum | Sun Jul 14 22:28:37 EDT 2013 | cedric77
1.Weight the paste 2.reflow the paste 3.clean the residue from the reflow ingot 4.weight the ingot By using simple calculation we can extract the percentage of metal or flux loading from the solder paste.
Electronics Forum | Tue Jan 07 23:38:08 EST 2014 | m_imtiaz
want to know the tolerance the paste height in the solder paste printing. for example if stencil thickness is 7 mil, what will the acceptance level of paste height ( upper and lower) kindly share if any guidelines or formula for the same
Electronics Forum | Fri Jun 19 22:10:18 EDT 2020 | davef
Don't get yourself wrapped around the measure solder paste viscosity axel. Observe the paste handling and preparation instructions provided by your solder paste fabricator.
Electronics Forum | Mon Jun 22 16:33:59 EDT 2020 | davef
Measuring solder static paste viscosity is fairly easy to do. IPC TM-650 .4.34, Solder Paste Viscosity lists the method and equipment. Just don't tell your customer that it is meaningless because the solder paste is printed in shear, not statically
Electronics Forum | Fri Dec 11 17:34:24 EST 2020 | proceng1
You can run it on a carrier board to catch any paste that falls. When we do Pin in Paste, we sometimes over print the apertures a bit to get the extra paste volume.
