Electronics Forum | Thu Jun 19 20:52:19 EDT 2008 | davef
Please give us more information about the source of the solder that you mention. Is it: * HASL applied by your supplier * Solder on pads after wave soldering * Solder paste after printing * Solder on pads after reflow soldering ... or what?
Electronics Forum | Fri Mar 26 15:48:31 EDT 2021 | grahamcooper22
Leaded HASL on small pads can be quite difficult to print on...the HASL tends to be domed rather than flat..and that can affect print quality...you really need a perfectly flat pcb pad to print paste on when you are assembling 0.5mm QFPs. If the pcb
Electronics Forum | Tue Mar 20 15:59:15 EDT 2007 | blnorman
We use preprinted labels and laser coding. For PCB we laser mark with CO2 (NdYAG for the aluminum heat spreaders). We either have an epoxy legend to burn out or we burn the solder mask to expose the copper ground plane underneath. Laser is a much
Electronics Forum | Fri Mar 09 05:06:09 EST 2012 | grahamcooper22
Is your solder paste deposit drying out? Or if the paste deposit is small or there is insufficient paste then the tack between the device and paste will be poor so it can easily come out of the paste during its placement or placement of other parts.
Electronics Forum | Tue Sep 07 09:11:33 EDT 1999 | Dave F
| We've noticed that there are many different recommendations for pad sizes for various SMT parts. This seems to vary wildly from manufacturer to manufacturer for the same case sizes. Is there any standards that can used used to specify these sizes
Electronics Forum | Tue Jul 23 11:06:00 EDT 2019 | majelacquinn
Currently trying to get away from using stencil printing. Looking for information on Micro-Dispensing and dot size using a Vermes MDV-3200A micro jet dispenser. I am using a Indium led free solder that has size 6 balls. With a 100 micron dispense hea
Electronics Forum | Mon Jun 30 08:55:31 EDT 2008 | davef
It will be tough to find a dimensional thickness specification for HASL. IPC-6012 Table 3-2, line "Fused tin-lead or solder coat - Coverage and Solderable" states the requirement that there has to be complete coverage of solder on the land, and it mu
Electronics Forum | Fri Mar 03 09:48:06 EST 2000 | Wolfgang Busko
I have heard about it. The main reason is to save money. The problem is, or better is said, that the mixing isn�t that simple for you got have a homogen paste afterwards and the solderballs shouldn�t be deformed in size so that problems during printi
Electronics Forum | Fri Mar 03 09:48:06 EST 2000 | Wolfgang Busko
I have heard about it. The main reason is to save money. The problem is, or better is said, that the mixing isn�t that simple for you got have a homogen paste afterwards and the solderballs shouldn�t be deformed in size so that problems during printi
Electronics Forum | Mon Jul 07 21:33:15 EDT 2014 | andrespena
The problem about covering it with glue (without using solder) is that the components might dislodge by a miniscule amount underneath the glue. So maybe the contact points will disconnect. I'm not sure if this will be a real problem, but if so it wo
