Electronics Forum | Mon May 10 16:37:01 EDT 2004 | davef
First some definitions, the two main types for solder masking near BGA pads are: 1 Pad, Non-Solder Mask Defined. In circuit board design, pads with spacing that does not allow solder (usually bumps) on the pads to contact the adjacent solder mask. [
Electronics Forum | Mon Nov 08 17:47:58 EST 2004 | davef
Russ: On "usually get some mask material from our board house. It cures with heat so it works really well in our applications.": We're unsure about the type of mask that you are using, but be careful [we used to do this, also]: * Final cure of the L
Electronics Forum | Mon Nov 08 12:47:52 EST 2004 | clampron
Good Day Everyone, I have a BGA rework that has some chipped/damaged solder mask that will need to be repaired prior to BGA replacement. I was wondering what materials are being used in the industry for this type of application. Any help would be g
Electronics Forum | Mon Nov 08 15:10:52 EST 2004 | russ
We usually get some mask material from our board house. It cures with heat so it works really well in our applications. Be wary of the "overcoat pens" they don't seem to hold up under heat and thre solder will flow right underneath it during BGA a
Electronics Forum | Mon Nov 08 13:38:37 EST 2004 | davef
You need to cover the chipped areas with a protectant coating, like epoxy. Look here:http://www.circuittechctr.com/products/115-1322.shtml We have no relationship, nor receive benefit from the company referenced above.
Electronics Forum | Mon Nov 08 18:05:18 EST 2004 | russ
Looks like we have been running the cure a little short (but only by about 44 min). I need to check if elevated temp shortens cure time to 1 min. at 700F! Thanks Dave, much appreciated Russ
Electronics Forum | Tue Nov 09 10:44:13 EST 2004 | russ
I guess i might want to throw this in for future reference. After speaking with our board supplier he states that this mask is fully cured when it reaches approximately 180C. I beleive this since we usually probe the repaired area after putting the
Electronics Forum | Tue Oct 19 19:25:40 EDT 1999 | Jeff Sanchez
Carol, I think the guys are right about you stand off problem but I want to address the wrinkleing of your masking. Although I think the temps you are subjecting the board to are very high and more than likely creating problems of their own. I th
Electronics Forum | Wed Dec 18 10:10:07 EST 2002 | davef
No, sorry not on "Dave's Bookshelf". My basis is a study done at IBM. I reference it here: http://www.smtnet.com//forums/index.cfm?fuseaction=view_thread&CFApp=1&Thread_ID=4941&#Message19050 Responding differently, you're correct. If you have a
Electronics Forum | Tue Oct 19 19:44:19 EDT 2010 | laen
I'm looking to mix up a batch of purple solder mask. Has anyone found a good ratio of red and blue that produces a pleasing purple? 50/50 produces a pretty ugly grape color. Is there a standard ratio most fabs use?
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