Electronics Forum | Thu Mar 05 09:54:59 EST 2009 | davef
When you measure "solder paste heigth of 7 & 8 mils using a 5.0 mils stencil," are you measuring the top of a flat brick? Sometimes if you snap-off the stencil too fast, the paste touching the stencil walls form peaks along the edge of the brick that
Electronics Forum | Thu Apr 06 15:47:09 EDT 2006 | jbrower
Last week I had the opportunity to get a sample of AIM SN100C solder paste. The SN100C paste was very nice to work with. My initial observations was that the paste had a very light odor, much less than the Alpha UP78 paste that we are currently
Electronics Forum | Thu Mar 31 06:09:19 EST 2005 | amstech
Yes, components do contribute to the non wets in fine pitch reflow. Oxidation is the main culprit. May ask where it is coming from. Can not say in particular. May be burn in test process or end of line baking, hot / cold testing and need to run DOE'
Electronics Forum | Fri May 26 10:49:32 EDT 2006 | pjc
250C peak temp seems very high for components. Thermal damage, which is latent like ESD damage, can occur on components at temps as low as 235C. Looking at component specs to see what the max temps are is a good idea I think when doing Pb Free trials
Electronics Forum | Mon Dec 29 14:47:36 EST 1997 | justin medernach
| how to determine the optimum solder paste height ? Ray, This is a gross misconception within the industry. There is no optimum solder paste height, per say. The effectiveness of a solder joint should be quantified in volume. Use your process as
Electronics Forum | Sun Mar 26 19:02:05 EST 2006 | ms
Hi We are running automatic stencil printers, open squeegees, stainless stencil, stainless blades, print speed 25-30mm/sec. We have a frustrating consistency issue printing .37x.3mm apertures on a 45pin LGA (11 pads each side, 1 large ground in mid
Electronics Forum | Fri Nov 02 09:09:56 EDT 2012 | davef
Sure you can use it it with leaded HASL. Recognize that ... * Your Sn42/Bi58 will no linger be Sn42/Bi58 * Your leaded HASL will no longer be the same leaded HASL that walked in the door to your plant * Lead from HASL coatings can diffuse through the
Electronics Forum | Tue Nov 22 08:11:36 EST 2005 | davef
It sounds like you're exhausing your flux activity on this component proir to reflow. We'd start with the reflow recipe suggested by your paste supplier. If the component lead doesn't flow well try: * Raising the peak temperature in 5*C increments.
Electronics Forum | Tue Nov 29 12:16:29 EST 2005 | Inds
MKS, You do not need to reach a temp of 245C to form a joint and surely not for 0603s. Since you are using such a high temp your flux is getting dried out.. Also if you are going to reach a peak of 245C on a brd that has Sn/Pb compt and Pb-free.. yo
Electronics Forum | Fri Oct 31 13:06:42 EST 2003 | Kris
Hi, What would also be important is the time above 217. 20 secs above 225 may be the same as 45 secs above 218 That 7 degres might just buy you enough to sweep the non lead free components through Has anyone tried 220 or 218 peak temp but at lo