Electronics Forum | Fri Mar 15 18:26:51 EDT 2013 | hegemon
We avoid kapton in this situation due to the thickness. 1 mil additional thickness can equal up to a 20% increase in paste volume at adjacent pads if you are using a 5 mil stencil. But then again, that is not always bad. But must be taken into consid
Electronics Forum | Tue Sep 24 12:49:43 EDT 2002 | dragonslayr
Aperture reduction @ 5 mils thickness is your best bet. It may take several attempts to get just the right paste volume. What aperture reduction was specified to the stencil house for these specific LEDS? or was the stencil blindly produced using a
Electronics Forum | Fri Nov 30 00:33:37 EST 2001 | jamstart
It will be a 'risk' to rely the volume using cyberoptic as it does not tell you the true volume. With no disrespect to them, they are only using 'mathematical' calculation (LxBxH)to get the volume. As we know that the paste will never be a flat surfa
Electronics Forum | Thu Apr 12 04:17:08 EDT 2018 | buckcho
Diego, I dont know how this machine works. Maybe they patented some way of measuring. But the idea of Mr. Evtimov is very good. Measure the pad only and see its value. If it is not 0, you have to know why, maybe ask the machine supplier. Also like Mr
Electronics Forum | Fri Jul 07 13:37:46 EDT 2023 | davef
Use the volume of paste of your circular aperture as the starting point. Calculate: Volume = pi X (aperture diameter^2 / 4) X stencil thickness Determine the sides of your square aperture using the volume of paste that you calculated and the stencil
Electronics Forum | Mon Nov 26 23:05:05 EST 2001 | ianchan
M.Parker, thanks a million!
Electronics Forum | Wed Nov 01 11:31:39 EST 2000 | Fraser
Is it possible you could simply over print to achieve the same paste volume? Supply me the numbers and I will do the calculation for you. Cheers
Electronics Forum | Wed May 30 10:21:10 EDT 2001 | Steve
Rather than meausre the stencil, why not measure it's output. The stencils function is to gage the right amount of solder in the right location. If you are measuring paste volume and you are tracking via SPC, you will begin to see a degradation when
Electronics Forum | Thu Oct 16 18:22:40 EDT 2003 | Gabriele
Russ, you are right, I've seen briging on 16 mils pitch on OSP (ref under N2),to avoid it needs more care in paste volume. Easier was by 63/37 (Clean) and N2 (on OSP double sided PBA). Regards Gabe
Electronics Forum | Sun Mar 07 19:53:38 EST 2004 | praveen
Hello, Voids in BGA can not be eliminated. You can only minimize them by reducing the solder paste volume. Try to bake the plastic BGA's and PCB both as per the standard. Check the PCB at the BGA locations if the via's are masked.Masked via's result
