Hi! Usually, the amount of solderpaste you need is very precisely given by any normal solder paste stencil. If you are ordering from a PCB manufacturing website like Aisler or JLCPCB, it's fairly cheap to get the stencil ordered together with the PCB, and when used properly, it gives very good and repeatable results for soldering.
If you are applying solderpaste manually, I would say that you should aim for a roughly 0.5 to max 1mm (thanks for the pointer, WestfW) thick blanket of Solderpaste above the pads you want to solder. For ground pads for QFN or similar chips you should go for a bit less, to prevent excess solder paste from squishing out.
I do recommend going for a bit less, rather than too much. It's easy to add a bit of solder after hot-air-flowing, but it's always annoying to have to deal with excess solder, especially with hard to reach pads like for QFN components.
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Hi!
Usually, the amount of solderpaste you need is very precisely given by any normal solder paste stencil. If you are ordering from a PCB manufacturing website like Aisler or JLCPCB, it's fairly cheap to get the stencil ordered together with the PCB, and when used properly, it gives very good and repeatable results for soldering.
If you are applying solderpaste manually, I would say that you should aim for a roughly 0.5 to max 1mm (thanks for the pointer, WestfW) thick blanket of Solderpaste above the pads you want to solder. For ground pads for QFN or similar chips you should go for a bit less, to prevent excess solder paste from squishing out.
I do recommend going for a bit less, rather than too much. It's easy to add a bit of solder after hot-air-flowing, but it's always annoying to have to deal with excess solder, especially with hard to reach pads like for QFN components.
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two millimeter? Did you get your units mixed up? Leave out a decimal point?
Stencil thickness seems to run 0.12 to 0.15mm ! ( https://www.7pcb.com/blog/stencil-thickness-calculations.php )
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I think I got some things a bit mixed up there, yeah ^^'
Thanks for the pointer!
Eh, worst case you rework the thing with a bit of solder wick. Without a stencil that might happen anyways.
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