Electronics Forum | Thu Jul 10 09:55:47 EDT 2003 | davef
A reading of the pictures is: A1: Looks like pad [B1] is smaller than the other pads. It�s weird that the pads are such different colors. A2: Looks like pad [B1] is smaller than the other pads. Solder mask opening [B1] is misregistered and seems s
Electronics Forum | Wed Jul 09 16:01:10 EDT 2003 | russ
Mike, the one pad that is "small" definitely appears to be over etching (It looks like it was supposed to be much larger). What is the dims of this little bugger as compared to the Gerber? i would also tend to believe that there probably is some mask
Electronics Forum | Wed Jun 18 20:27:28 EDT 2008 | davef
No, we not sure if your solder mask is LPI. The article we linked was aimed at solder mask application methods. LPI is the most common mask in use today. So, what kind is it? Green tells you nothing. Solder mask can be a variety of colors.
Electronics Forum | Wed Jun 18 08:57:45 EDT 2008 | more_sunshine
thanks for the post... but are you sure that the type of mask i mentioned is photoimageable and as i understood can be removed from desired places (pads/soldering areas) using uv and developer (which i don't know what material is it). and also the
Electronics Forum | Thu Jun 19 04:16:11 EDT 2008 | more_sunshine
actually this is my little problem, i don't know about the material except that it comes in a paste form and it has to be diluted with acetone and it has a green color. i wish that the compounds used to make a solder mask aren't that numerous to be d
Electronics Forum | Thu Feb 24 11:05:53 EST 2000 | Russ
I usuallly like to have the pad size the same size as the ball up to +2mil, the pcb solder mask opening to be +4 mil from the pad size (I have found this to aid in Xray inspection for opens since you can see the little tail of the solder wicking up t
Electronics Forum | Wed Jun 18 08:07:58 EDT 2008 | davef
Here is a link to a basic discussion of solder mask application methods: http://www.ami.ac.uk/courses/topics/0221_smp/index.html
Electronics Forum | Thu Mar 19 20:12:32 EDT 2020 | slthomas
Stephen, you are spot on with your description. Here's a .jpg with paste layer, copper, and solder mask.
Electronics Forum | Thu Feb 24 10:52:41 EST 2000 | JAX
Robert, Here's my recommendation's: Solder paste opening on screen should equal the solder mask opening on board. Stencil thickness at .008" but this should not be your main concern as stencil thickness should be determined by the fine pitch that ar
Electronics Forum | Thu Feb 24 10:52:41 EST 2000 | JAX
Robert, Here's my recommendation's: Solder paste opening on screen should equal the solder mask opening on board. Stencil thickness at .008" but this should not be your main concern as stencil thickness should be determined by the fine pitch that ar
